Previous Tool / Carving Tips
Updated 05/31/2018

All tool tips are subject to copyright laws, and may only be used with authorization from PJL Enterprises or the original author.

1997:
May Tool Tip: Its about burner cords, and how to keep them from being a "drag".
June Tool Tip: Some tips on transferring your design to wood.
July Tool Tip:
This months tip is on collet and bit care.
September Tool Tip: Some alternative ways to clean your burning tips.
November Tool Tip: A "Sticky" Situation, and how to avoid it.
December Tool Tip:
A few computer pointers.

1998
March Tool Tip: How to use the number "13" pen tip to make fish scales.
April Tool Tip: A Beeswax finish, used on fine violins.
May-June Tool Tip:
Another use for your pyrographic burner unit.
July-August Tool Tip: How to make pictures of your carvings download fast (for carver websites).
Nov~Dec Tool Tip: A discussion about dust collectors. Design do's and don'ts.

1999
July-August Tool Tip: Pyrography systems, theory and application.

2000
January Tool Tip: An easy way to make a lateral line on fish carvings.
October Tool Tip:  Another way to transfer patterns to wood.
December Tool Tip:  How to make fuzzy hair, for my teddy bear.

2012
January Tool Tip:  Total Cost of Ownership (TCO) or How much does that tool "really" cost?

2015
October Tool Tip:  Going, Going, Gone... or
How to prevent your pyrographic art from fading

 

May 1997 Carving & Tool Tips

This month's tip is about burner cords, and how to keep them from being a "drag".

Because our pens are so light weight to begin with, even our superflex cord can seem like a "dog's tail" that your having to "drag" around with the pen whilst burning. To remedy this problem, I suggest that you first find a fairly small rubber band. Next, on the end of the cord that attaches to the pen, fold the cord over onto itself once. Use the rubber band to secure the cord, so it stays folded over onto itself.

Now when using your pen, just have the cord go between your thumb and trigger finger so it rests in your palm. You'll be amazed how your cord creates no "drag" now. Some people even use an armband to have the cord follow their forearm, so that the cord is totally out of the way.

Originally told to me by Laurie Gmyrek and Steven Chlupsa.

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June 1997 Carving & Tool Tips

This month's tip is about relief carving, and an easy way to do lettering. Also some tips on going about transferring it to your wood.

For anybody who has the need to do some lettering, to eliminate the chore of setting it out. May I suggest a visit to this site and pick up a shareware copy of an easy to use program called poster, that takes all the hard work out of it. Poster Software (http://users.aol.com/PosterSW/)

This little jewel was submitted to Bill Judt's woodcarving list (http://wwwoodcarver.com/WWWList/WWWList.html) by a Malcolm Chorley I believe, and talked about by many others.

Another subject that kind of goes along with this, is transferring a pattern to a block of wood. This too has been discussed at length on the previously mentioned list server. Various techniques can be used, from using plain carbon paper and tracing your design, to laser printing or photo copying a "reversed" image and ironing it onto your wood.

If you own an ink-jet printer, you can do the same thing as you would with a laser printer, except that you print it on acetate transparency film and immediately press it to the block of wood using a roller or squeegee, (ink-jet ink doesn't dry very fast on regular transparency film). The acetate can be cleaned with a damp cloth, towel dried, and reused many times. This is something I developed for my mom's arts & craft business, works great for intricate patterns and curved surfaces. When doing a "production run", I can usually get each print impression to transfer twice; although the second one may be a bit light.  Of course, this doesn't work to hot (no pun intended) with flat work pyrography, as there is no way to erase pattern lines (i.e. it works best for tole painting or sculpture pattern cutting).

As with anything you haven't tried before, use a scrap piece of wood to test with first, it also helps if the surface of the wood is fairly smooth.

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July Carving & Tool Tips

This months tip is on collet and bit care, submitted by Laurie Lundell (Gmyrek)

Ever bent your favorite bit trying to get it out of the collet, or just hate the hassle of trying to get a stuck bit out of a collet? You might be thinking, "just unlock the collet, and push the bit in further if possible". That will work, but you might damage your bit if your not careful. The real cause is that the insides of your collet(s) have wood resin build up, which causes the collet to kind of glue itself to the bit.

To clean (for example an Optima 2 hand piece) your collet set, you can use a few items usually found around the house. Soaking the collets (and collet cap) in plain finger nail polish remover or rubbing alcohol (oven cleaner will work too, but keep it off of any aluminum parts) will quickly remove any resins. The parts of the hand piece shaft that the collet(s) have contact with should be cleaned with the same thing, using a damp (not dripping wet) cotton swab. DO NOT get any of the cleaning solution on any bearing, as it may penetrate and damage it which will lead to premature bearing failure. Finish by drying the collets and other parts (use a thin wire to thread a thin piece of yarn through the collet holes for drying, do not force it through), and then giving them a thin coat of light oil (like WD-40), and wipe clean again with a cloth or Q-tip. Again, DO NOT get any of the light oil on the bearings.

If you have very humid conditions like Minnesota does, another cause of stuck bits is plain old rust. On bits that have already succumb to the ravages of moisture and are rusted...Spray with WD-40 or oven cleaner in a cup and let them soak...then take a wire brush to them and/or steel wool to the shank, wipe clean, spray again, then wipe clean...voila......like new! it is a good idea to spray all of your bits with a little WD-40 from time to time to prevent rust in the first place.

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September Carving & Tool Tips

I have never been one burn light when using my burning pens. I am also too lazy or too busy to constantly buff off carbon build up when using them (I usually use them to "score" plastic). This of course leads to heavy carbon build up on my tips, to the point that it can't be easily buffed off. I am also aware that heavily buffing a tip can cause the metal on the side of the tip to "roll over" the sharpened edge. Which would mean I'd have to then resharpen my pen tip to burn a decent line, which of course will lead to a shorter tip life, etc, etc....

If you too have these bad habits, don't reach for the sandpaper just yet... Their is an amazingly simple and inexpensive solution to this problem. You probably already have this product somewhere in your house. Go look on your shelves, or under the sink for that can of oven cleaner. Yes, oven cleaner!

Be mindful to read your oven cleaner directions, as it may be harmful to certain metals (not to mention yourself). The nichrome tip itself should not be a problem, but the the brass tubes and silver solder that is connected to the nichrome tip may not like certain oven cleaners. If so, just be careful not to let the oven cleaning foam or gel touch the silver solder or brass parts of the pen.

I myself like to use "Diablo Carbon Kleen", which is safe for all metals (but still pretty toxic). This stuff is a gel like substance that comes in a can. You'll have to go to a restaurant supply store to find it though. An overnight soak, then wiped clean, followed by another two hour soak usually gets 90% of the carbon off of my once heavily carboned tips. At that point I can usually buff off the remaining carbon build up with ease.

You may have to experiment with your particular oven cleaner to see what the optimum soak time(s) will be, and whether you'll need to do it more than once or twice.

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November Carving & Tool Tips

This month's tip was submitted by Laurie Gmyrek. Laurie is an accomplished wood carving artist who also does stained glass. Visit her web site to see some of her past and present works.

A "Sticky" Situation

In competition, we are subject to stickers being placed on our carvings, for identification purposes. This year I have a piece that has been damaged by a sticker, twice. The damage did not occur until the sticker was removed. When this was done, the finish, the paint and the gesso under-coating, came off with the sticker, leaving only the deft-sealed wood behind.

The repair of this seems simple enough, but just painting the damage does not fill in the thickness of the surface that was removed. Try as I may, the color was right, but from the side, in the right light, the slight depression can be seen. The only way to rectify this would be to start from scratch by removing the surface treatment completely and starting over with a new finish. Unfortunately this is not always possible, and a real pain in the neck!

Until the competitions use stickers, which are "surface friendly", this kind of damage along with adhesive being left behind, can occur. My tip for this month would be to use a hairdryer to heat the sticker and it’s adhesive, prior to trying to remove the sticker. This seems to solve the problem, but you need to remember to do this, prior to attempting to remove the sticker.

Hopefully this tip can keep someone else from having to deal with a "sticky" situation.

Laurie J. Lundell Gmyrek

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December Carving & Tool Tips

This month I thought I'd would give a computer few pointers. Yes, I know it really has nothing to do with carving or carving tools "directly", but you are using your computer to view this (aren't you?).

Arghhh! My internet connection is too slow!

A few months back I purchased a brand new 33.6 Cardinal modem. To my disgust, it didn't seem that much faster than my old modem (a zoomview 14.4bps). After much internet searching, I came across a web sight called Windows 95 Annoyances which was very informative on what the "real" problem was (it has many other windows95 fixes too). Windows 95, by default, is optimized to run on a LAN or Ethernet like connection, which have considerably higher bandwidth compared to a 33.6 modem. There is a setting in the Registry file called "MAXMTU", which is set to 1500 by default. This high of setting can cause a router (between you and the site your looking at) to "hang", or send IP packets out of sequence. At any rate I edited my registry file, and gained at least a 100% speed up when downloading a web site or file. Of course most people are not technically inclined enough to even think about rooting around the registry file, so an easier (and just as effective) way to fix this is to get a FREE program called "Mtuspeed" at the MTU-Speed Home Page. Like anything else, remember to read the program directions first.

Drat! My friend is online again, so I can't call him/her!

To see if a friend or relative is currently online, get a program called ICQ (Sounds like: I seek you) from Mirabilis. Of course the person your looking for must also have this program, have it running whilst online, and be in "online" mode to be seen. ICQ not only lets you know if a given person is online, but will also let you start up a chat window with them (more than 2 can be in a chat session). You can even use it to run 3rd party communications programs like Microsoft NetMeeting, send URLs, send or receive files, send and receive quick messages, and much much more.

Help for the carvers web site (with large photos).

You'd like to set up a web site to show off your carvings and you have all the equipment you need, but you don't have a clue when it comes to html coding. Neither did I for the most part. For about $150.00 (or less) you can get Frontpage98, which is pretty much like working with a work processor (no knowledge of html is necessary). This entire web site was made using Frontpage97, and required very little manual coding of html code. I hear that FP98 is even better than FP97.

When designing your web site, you can get some ideas by looking at how other people have done theirs (go to my links page for some good examples). Some design caveats that should be followed: 1. DO NOT to have pages buried more than five layers deep from the initial start page of your site (makes it hard for people to navigate your site). 2. If using frame sets, remember to also have your site links (and email link) somewhere on each page (in case the person's browser doesn't support frame sets). 3. PLEASE pick a text color and background color or bitmap image that does not cause blindness (yellow text on a cyan background comes to mind ;-) 4. Have a few people you know (with different screen resolutions and different browser software) test out the "viewability" of your site, as it may look totally different from what you see on your screen...

Looking at web sites with photos of carvings is getting to be a hobby with me ;-) The one thing that can really distract a person viewing a site are BIG JPEG files that seem to take forever to download. A neat little program, called Cyberview, can help cut the fat out of your large JPEG files. Remember to always save your JPEG files at 100% quality before using Cyberview, in the same "size" (height & width) as you want them to display on the browser, and that 96 dpi (dots per inch) is sufficient for most people. (640x480 screen resolution is equal to 72 dpi, 800x600 = 96dpi.)

Another thing to consider is how you scanned a photo of a carving to begin with. A wealth of general information about scanning techniques can be found at Wayne's Scanner Page.

Another tip (I don't remember if Wayne mentions it) is to never save your newly scanned file as a JPEG file. Why?!? The JPEG file format should only be used after ALL of your editing is completely done. I use the compressed TIFF format, then save the final edited version as a JPEG. For example: If you open a previously saved JPEG file, and then run an "unsharp-mask" (sharpening) function on it, it may get blocky and somewhat pixilated (sharpening a JPEG file has a tendency to make "defects" in the compression process show up). In fact; if you open, edit, and save to a JPEG file several times, the image quality will noticeably degrade.

GIF vs. JPEG: Using the wrong file format can cause a given image to be too large and/or look bad. A general rule of thumb to follow is: JPEG format should be used for 24bit photographic files only. It is not very good at compressing computer generated vector graphics (like text or icons). The GIF format is best suited for computer generated graphics and text. You can use GIF for small "thumbnail" photos, but they will have to be in an eight bit format (256 colors), and photos are smallest with a "diffusion screen dither".

Whew! I hope these tips will help out you wanna-be webmasters in getting that perfect carving site, up and running.

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March Carving & Tool Tips

This month I'll be showing the technique of how to use the number "13" pen tip to make fish scales. This technique was originally shown to me by Scott Clinton at last years Northern Nationals in Bloomington, MN. I believe that Scott is the originator of this technique, and teaches it to his students.

Step 1, the scale.

As shown here to the left, you make each individual scale by holding the pen's flat surface to the wood and making a crescent however wide you need it to be. Keep the pen tip orientated the same throughout the stroke. Use the pen's heat and shape to depress the wood more in the middle third of the stroke, and depress a bit lighter on the ends. You'll find that rotating the the tip slightly as your doing a scale, makes it a bit easier to control.

Step 2, the second scale..

Make another like the first one, starting at about a bit more than a third to a half of a scale width over from the first one.

 

Step 3, the third and final scale...

The "joining scale" is made pretty much like your first two, and should connect approximately* 1/3 from the end of each of the two scales it is connected to. Voila, you've just learned the three basic steps to fish-scale carving using our number 13 pen tip.

 

Some Additional Notes.

Obviously not every scale on a fish is going to be the same size, as you will need to have smaller ones near the belly, gills, and tail fins among other places. The beauty of this technique is that you can rapidly change scale sizes, and can be done in reverse of what I've shown here (start with bottom scale, then make the other two on top, etc...). Another advantage of this tip and technique is quite evident when doing the inside of a curved fish body (hard, if not impossible, to do with most other types of scaling tips). Remember, this "basic" technique is not set in stone, and can be strayed from somewhat liberally to get the effect that you need (i.e. every scale should not meet "exactly" 1/3 from the edge of the adjoining scales, as in real life... everything is approximate....).

If your having a hard time going from one side of the scale to the other evenly, you can alternatively go from each end of a scale and join it in the center. This is usually the easiest for beginners, or if you have limited dexterity. This technique is easiest if you don't try to "over texture" your fish. Most fresh water fish I've handled do not have a very deep texture to their scales any ways.

Many carvers draw out with a pencil where they intend to burn their carvings, this is not necessary or even recommended. Because this is somewhat of a "freeform" way of making fish scales, it is very hard to try and stick to a drawn pattern whilst doing. If you make a mistake while burning, oh well... Fish don't have perfect scales any ways, and you can easily cover up an occasional mistake by making it look like a scar or "mutant" scale. To illustrate, my daughter caught a sun fish last summer that had a good sized chunk of meat removed towards the front of its dorsal fin, which had even regrown scales over the scar.

This pen tip is available in three sizes: Small, Medium, and Large. The small one is good for doing miniatures, trout scales, or if you prefer it to the medium size for doing the smaller scales on your carving. The Medium sized tip is the most versatile, and can be used to do all of the scales on most life sized fish carvings. The Large sized tip is good for when your working on big carvings or scales, and can do most of the same work the Medium is capable of (really small scales are nearly impossible though). The size of tip you choose primarily depends on the size of your work, and your personal preferences.

This pen is offered in both standard and heavy duty styles, but I recommend getting it in the heavy duty style along with a heavy duty cord too. This pen began life for use in flat work pyrography, and is slightly different from the original in that the tip should not come to a "sharp" point. Instead, its tip is "very slightly" rounded at the point, so that it doesn't gouge when you are in the middle of the scale stroke. If you get this tip, or have a similar one, you can remove any sharp point by just running the point across a piece of sand paper once (once is usually enough).

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April Carving & Tool Tips
Published 4/5/98

This month's tip was contributed by Michael Dunn, a multi-talented artist who has a very interesting and unique website of his own. This is how the "professionals" in Switzerland finish violins, so now you know another little secret ;-).

When I was in Brienz, Switzerland learning to carve at the Schnitzlerschule there, they had a section of their school devoted to violin making. The basic final finish was beautiful, and I found out its also very simple.

Shave beeswax into a small jar, press down firmly but not hard enough to make it a wad again, and then cover it with turpentine and let it sit overnight in a warm place. In the morning you'll have a paste or thick liquid, depending on the ratio of wax to turpentine. You can adjust it by adding one or the other. I prefer a thick paste. anyway, you rub it on like any wax, and wipe it off lightly to get any thick places smoothed out. Let it sit for 24 hours, and rub it out again, hard until its shiny. Do it again twice, same time interval, and then polish it smooth.

It may take some work, but its the best final finish I ever ran across. Ideally you would re-wax it about once a month for a few months, and then once a year to bring out the shine again. It gets better each time, and it'll take the three initial coats to look right.

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May-June Carving & Tool Tip
Published 6/19/98

This month's tip was originally shown to me by Steve Chlupsa, president of SMC Enterprises.

If you have a pyrographic burner, like the Optima 1 for example, it can be used for texturing / burnishing / cutting wood, leather, gourds, AND airbrushing. Yes, airbrushing! Well, making stencils for airbrushing at any rate ;-)

Many carvers and airbrush artists use an acetate or frisk mask to better control where the paint is applied to. If you have a pyrographic burner unit that has stable lower temperature settings (like the Optima 1 does), it can be used to "score" acetate and similar masking materials instead of using an exacto knife or razor blade. In fact it works much better than exacto knives and razors, as you have a sharp "heated" blade. Its also much safer, as your less likely to cut yourself using this technique than you would with a razor or an exacto knife.

With this technique, you can use thicker acetate that what you would normally use for airbrush masking (it won't tear as easily). If you want to print a pattern onto it first using a computer printer or copier onto standard or inkjet transparency, that will work just fine too. After you've drawn, printed or copied your pattern to the acetate, you'll want a score it on a glass surface (won't dull the blade, hard backstop). BTW, A back-lit glass top table works excellent for doing this. You'll want to make sure your burning pen tips are sharpened AND polished, as it works much better if they are polished (glides better, acts sharper, no "burs" to snag on plastic).

Now, you do not want to melt all the way through the acetate when doing this. You just want to score it most of the way through, so that you can just pop out the pieces like you would on a puzzle (another reason why thicker acetate works nice). So keep the temperature low, and don't let your blade stand in one spot for any reasonable length of time. With a little practice, you'll be able to make stencils like the professional airbrush artists do.

You'll want to use a pen similar to either the Optima 1's "Standard Skew" (#1) or "Small Skew with rounded heel" (#12) for this. You'll pretty much only use the point of the pen tip in doing most of this (not the whole blade length, unless you are doing long straight lines), so the #12 style pen may work better in some situations, as it is designed to take a turn at a very fast rate. If you are doing long straight lines, you'll want something like our Standard/Large Skew tip (using the whole blade length), and you'll have to turn the burner down even lower than if you were just using the point of the burning tip only. If you need to make very small "pin holes" in the mask, we have in the past made a special pen tip for that, which comes to a needle like sharp point.

As an additional related tip this month (as I kinda skipped May altogether ;-), here is how you can position and hold down your mask (in some cases) when your ready to start painting. Go to your local hardware store, Wal-Mart, etc... and pick up either a spray can of 3-M "Super 77" or Duro "All- Purpose Spray Adhesive" (the Duro stuff is less expensive). These adhesive sprays, act much like the glue on the back of 3-M sticky notes. Just spray it on the back of your stencil, wait a minute or two (read the directions first), and position it onto your carving. This is also a cool way to airbrush T-shirts and the like too. Obviously, to apply a stencil like this to a carving, in this manner, requires that the carving be flat in nature, or have a rounded surface on only one axis (a cylindrical shape will work, a sphere would not work). I guess if you were to use something like a thin rubber instead of acetate, you could do spherical objects too with a little work. If doing a T-shirt, and your all out of adhesive spray, you can also use something like an old dryer door and magnets to hold your stencil in place.

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July-August Carving & Tool Tip
Published 8/2/98

This is something I've learned over several years of using PhotoShop and other various photo editing software.

Because I belong to a woodcarving listserver, I get to enjoy seeing many carver's web sites. Unfortunately, not everyone knows the "magic tricks" of "super compressing" their digitized pictures to about one third the size they would be if processed and stored using the same file type. When the wrong file type is used to begin with, it usually means a bigger (and not as good looking) file, as it would have been if the correct file type (JPEG or GIF) was used.

Below is an extension to last December's tool tip, that gives you a step-by-step process of how to correctly process digital photos (from start to finish), and how to super compress them too. I use PhotoShop 4.1 for my scanning and editing, so all the pictures and steps tie into standard PhotoShop routines, but can be done by most other programs like it. I obviously can't go much into taking the actual photo with a camera, but suffice it to say that "nothing beats a good SLR camera" (especially with good lighting and a macro lens).

Step 1. Scan your picture. This sounds like the easiest, and it should be (if you follow a few general rules). First of all, make sure your scanner's glass is clean and lint free. Don't use paper towels, they can scratch glass because they are made of wood fibers. Office Max sells a 12 pack of lint free "cloths" made to clean optics of this sort for $5.00, and its well worth the money. For scanning web site pictures, I like to scan photos in at 96 dpi resolution (as most people are using at least 800x600 resolution monitors now days). BTW, 72dpi is equal to a 640x480 pixel resolution monitor. If I want them to display larger than the original, I still use 96dpi, but set my "size multiplier percentage box" (that is in my scanning software interface) to what I estimate will be about 1 1/2 times more than what I'll need. If you don't have something like a "size multiplier percentage" thingy in your scanning software, but you still want to enlarge it, then go ahead and use a higher dpi rating. Just remember to resample it down to the correct size AND correct dpi. Resampling is one of the first things you'll need to do, in your photo editing software, right after scanning anyways. Remember to NEVER scan your photos beyond the "optical" scanning resolution of your scanner. Interpolation sounds nice, but the result are quite bad.

Step 2. Save your picture in a 24bit per pixel "lossless" file format (like TIFF). If you've already determined that you want to save a picture at a given size, you can resample it down to the correct size & dpi before doing this. I prefer to save it as I scanned it, and go back later and do all the editing on it (as I'm usually doing several photos a session any ways). Notice that I don't save a "Thumbnail" of the photo with the picture, as it save a little bit of space. Besides, I use a separate thumbnail viewer any ways which works much nicer. Go ahead and use any LZW type of compression that is appropriate for your computer.

 

Step 3: Make some duplicates. If your going to have a clickable "thumbnail" version and a enlarged version that the thumbnail is hyperlinked to, make two duplicates at this time. I like to suffix thumbnails with "sm" and use "lrg" at the end of the enlarged photos. After that is done you can close the already saved original file.

 

 

 

Step4: Cropping and Aspect Ratio.
If your going to have several thumbnails in a picture gallery of sorts, its nice if they are all the same size AND aspect ratio. With some scanning software, its pretty hard to calculate the proper aspect ratio for each photo prior to (or during) scanning, especially if you have different sized photographs. Notice that I'm using a 7x5 constrained aspect ratio for my marquee options (7"x5" is the original size of the photographs I'm working with here). This step is not always necessary, but its a useful technique. You can do this step before duplication "Step 3" on the already saved original, so your thumbnail and enlarged photo are exactly the same, just different sizes (just answer no when asked to overwrite original file when closing it). Most photo editing software will have some sort of information window up that shows the number of pixels your marquee is while drawing it. Make sure it reads at or above the size you wanted your largest version of the photo to display at.

Step 5: Resizing your image. Here you can see the menu selection and the dialog box that comes up after choosing it. The cursor is in the "Width" box, where I've changed it to 200 pixels like I did to all of the other thumbnails on the same page. BTW, I used 800 for the enlarged versions. Now all my thumbnails and subsequent enlarge photos will be the same size and aspect ratio when they display in by browser. Notice that I have the "Constrain Proportions" and "Resample Image" boxes checked (BTW, use Bicubic or "best" resampling if you have that option). If you had scanned your photo at a higher dpi (like 150) that what you want it to display at, this is the time to change that too. Be aware that your photo may degrade (read blur) slightly if you resize it several times, so try to do everything you need to do in this box at once.

Step 6: Sharpening (not tool sharpening either guys). Now you can finally sharpen this photo up a bit, so it looks good. In case you've ever wondered, almost all scanners cause your photos to be slightly blurred. So this is a necessary step to having great looking pictures on your web site. Notice that I'm using "Unsharp Mask", and not one of the other sharpening methods. This is because these other ones are "preset" defaults of the program, and are best used to sharpen vector graphics or B&W pictures. Unsharp Mask also gives you a high degree of control over the sharpening process, which can make a difference depending on several variables. The first field in the dialog box is "Amount". This field can generally be set anywhere from 150 to 220%. In other programs this field may be called "sharpness amount" and may be on a different scale than PhotoShop. The second field call "Radius" determines how far around each pixel the sharpening filter goes when sharpening. It is usually set anywhere from .9 to 2 (I find 1.2 or 1.4 effective enough for me). The next field is called "Threshold", and determines the threshold of the filter where it should and should not sharpen (you don't want to sharpen a large monotone area of the picture). Effective range on most photos is 5 to 20 (I prefer to keep mine at 9 though). Remember not to over do it when sharpening your photos (300% sharpening rarely looks any good). If you start out with a good looking in focus photo, you can usually stick with settings similar to what I have shown here.

 

 

Step 7: Saving your Pictures.
Sounds simple enough, just go File-->Save As, right? Well, not quite that easy. In this series of steps I've shown you, its assumed that you are working with a scanned image of a photo. Therefore the "recommended" file format to use is JPEG, and JPEG ONLY! You may recall from step 1, that I had not checked the "Save Thumbnail" box. When saving a photo for your web site, you shouldn't save a "thumbnail" inside the photo either. Don't be tempted to use the "progressive" save option of most photo editors either (it may look neat when downloading, but it makes for a larger file). Also, a JPEG saved with the progressive may not be compatible with all programs, especially with JPEG post production compressors like Cyberview. The reason I'm using the "Maximum" quality value of 10 in this example, is because I intend to process the photo through Cyberview (1.02 evaluation shareware version). Once you've save your Photo in JPEG format, you shouldn't go back and edit and the resave it again, as it will noticeably degrade each time you do it (that's why its called "Lossy" compression). That is why I saved the original scanned file in a TIFF format. If I do have to go back and fix something, I'd rather start with an unedited pristine photo and redo everything, than use one that will degrade each time its edited and saved.

BTW, if you've looked closely at the properties of the pictures I'm using in this tool tip, you'll notice that they are 3 bits per pixel GIF files (that's why the "photographic" parts of some of them look lousy). These types of files, that have only a few colors, are excellent candidates for the GIF file format. Others include very small icons, seen on most web sites, animation, or very small photographic thumbnails (under a inch square usually).

Step 8: More compression. To really make your JPEG photographic files as small as possible, get yourself a "super compressor" program like Cyberview. Click here to see a screen shot, or here to see it in a new browser window.

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Nov.-Dec. Carving & Tool Tip

On the various woodcarving newsgroups and list servers that I subscribe to, I often see carvers asking for tips and/or plans on building or buying a dust collector (bench top or laptop). The first question that is usually asked by carvers is "How expensive is it?". Because a dust collector is (IMHO) a safety device, the first question asked should be "How good is it at filtering dust?", and the second question should be "Performance?", and only then should "Cost?" come into the buying decision. You can't put a price on your health and safety, and why have a "Yugo" when you can have a decent one with three or four times the performance, for just a little bit more money. In fact, I started writing this article as a reply to someone's request for information on "inexpensive dust collector" plans, or ready made units.

Here are a few pointers (and a few things to chew on) for all the carvers out there thinking of making their own home made dust collector, or looking to buy a ready made commercial product. BTW, this article is geared toward "wood carving" dust collection systems, but most of the basic things still apply to ducted shop models (used for table saws and such).

Safety First!

If your going to make a home made dust collector, use an "INDUSTRIAL" grade mechanical filter. The filters in most hardware stores and such are made for filtering the ambient air in your house, not for stopping even moderate amounts of wood dust. I refer to these types of filters as "leaf catchers", because that's all they'll filter out. In fact, most are rated at; or less than 10% efficiency @ 10 microns when used within their airflow specs (and most aren't being used within spec). A good industrial filter should be capable of 97%+ efficiency at 3 to 5 microns, and 30%+ efficiency @ 1 micron. They cost a little bit more, but are well worth it. Remember, the idea is to "collect" the majority of the dust (hence, filter it out of the air), and not just recirculate it into your work area and lungs. By the way, always use a filter that has a CFM rating equal to, or above, that of the fan(s) that your unit will have in it (even an industrial filter will be "useless" if you exceed the maximum airflow efficiency ratings by more than 10%).

Don't get sucked into using an "electrostatic" type of filter either (washable or other types). I almost did once myself, because the "ASHRAE 52.1-1992" test sheet (here after referred to only as "ASHRAE") initially looked very good. I then asked the technicians at the company who did the ASHRAE testing a few important, and pointed, questions about how the test is performed and what some of the more obscurely named measurements meant. I found out some very interesting facts on how the tests are conducted, and how the report itself can be used somewhat deceptively to quote "efficiency".

Although electrostatic filters can claim a very high percentage of dust collected "initially", this one was even rated down to the sub micron level, they cannot hold very much of it. The 24"x24"x1" filter that was used in this test example (which claimed near HEPA filtering @ 1200 CFM), could only hold 60 grams ( 2.1428 oz.) of the synthetic dust that they used for testing (not very much by wood carving standards). Initially, for the first 10 to 15 grams, the filter was filtering at near HEPA quality. After which, its "efficiency" dropped off dramatically. The filter manufacturer had quoted ratings using one part of the "averaged" summary data. Because the filter was working at near HEPA standards initially (the first 10 ~ 15 grams), it skewed that particular average in their favor. Obviously a filter that has to be cleaned or replaced after you get more than a few tablespoons of dust on it, is totally impractical for a dust collector. I myself think that the current ASHRAE test was designed to test mechanical filters, which typically filter a better as you load particulate upon them.

After the fibers on this type of filter becomes loaded or "saturated" with dust, it starts to "shed" whatever dust tries to "cake" onto it, letting even large particulate through it. These filters work by using the airflow to induce an electrostatic charge in the filter media which is made up of two or three different interwoven materials (usually polypropylenes) that have different dielectric strengths. But when the media fibers becomes coated with dust, they no longer work at all. Even moderate sanding of your carving would saturate this type of filter up in a couple of minutes of usage, after which, the rest of the dust would go right through it.

I can't stress it enough! Stay away from so-called electrostatic filters!

Designing for filter efficiency and performance

A generally good dust collector design has the filter before the fan(s). This is because it is much easier to push particulate (dust) "through" any given filter media (not a good thing), than it is to suck it though any given filter media. To see this for yourself, take apart the heating and return ducts in your house. You'll notice that the return duct is dirty, while the heating ducts are much cleaner. This is true even if you didn't use a furnace filter at all, because dust will settle quickly in a vacuum (return duct), and won't settle in a high pressure air flow (heating ducts). With these basic physics in mind, its easy to see that a given dust particle will have more of a tendency to "drop" onto a filters surface or interior fibers when in a vacuum, than in a pressurized environment. This is why you'll see a "puff of dust" coming out of most bag filters when they are first started up (not to mention what you can't see during operation, because the air flow moves the dust too fast to be seen). It has been said (even by a few bag type manufacturers themselves), that the filter efficiency doesn't come up to spec until there is a coating/caking of dust on the interior of the bag (technically, their letting the dust do the actual filtering). All mechanical filters get more efficient as dust loads onto them, but bag type filters seem to rely too much on an initial dust film to work properly.

Putting the filter behind the fan(s) also retards the efficiency of most fan designs that I've seen (up to 50%, depending on the fan design/type), because of back pressure and turbulence this causes on the trailing edge of the fan blades. Another advantage to putting the filter first, is that it keeps the fan blades clean so they operate at their best efficiency (and you don't have to worry about dropping any large chunks of wood into it either). Also, when setting a filter before the fan(s), you'll want to keep a couple of inches of space between them, so the fan doesn't suck air through only one spot on the filter (Not doing so, can render a filter's efficiency rating "useless").

So why would anyone make a unit with a bag filter behind the fan(s)? Because its allot easier to design! This is because in a "filter before the fan" design, you have to design the whole unit around the filter's size and CFM ratings (and match it with the right sized fans with enough CFM & static pressure); if you want to make it portable (if you don't do that, it probably won't be very portable). Obviously, a bag filter can be almost any size you need it to be, as it is "external" and does not need to be placed in a housing of any sort.

Some more interesting "filter physics"

Generally speaking, the higher the surface area ratio of a given filter, to the unit's airflow ratio, the better its filtering efficiency will be at a given air flow (CFM). Simply put, if your using a filter designed to filter out 98% of 5 micron sized particles at 700 CFM, and the unit is capable of 700 CFM of airflow, then 98% of 5 micron particles and larger should be stopped. If you run the same unit at only 350 CFM, the filter efficiency increased dramatically, even getting the majority of sub micron particles (filter efficiency ratings are usually only quoted at the filter's maximum CFM rating).

This is where having a dust collector capable of variable speed is important. When doing rough out work on a carving, the types of carving bits used for this generally generate large volumes of larger particulate (I really can't see using a fine sanding drum for doing initial roughing out), most of which a good filter media should be able to handle even at its maximum airflow ratings. When sanding and doing detail work with finer bits/tools, you are generating allot less volume of dust, but usually much smaller particles. You should turn down the speed of the collector at, or just a little above, what is needed for adequate dust collection/removal, so that the filter media will then be capable of collecting the finer dust that detailing and sanding generate.  Cleaning out the filter before using the unit again at higher speed levels is only prudent, as the smaller particulate would may get pulled through the filter if turned up high again.

This is also where bag filters have problems.  The dust film on the top of the interior will have a tendency to fall off, because of the drop in pressure, which then lets a good deal of the smaller particulate through the "filter" media.

Focusing airflow (A.K.A. venturi action)

Obviously, using a smaller opening (smaller than the box or filter dimensions) where the dust is to be collected at, will give it better drawing power, because it speeds up the flow rate of the air at the "inlet" point (which is known as Venturi effect). The size of this opening is somewhat dependent on the fan(s) CFM, diameter, and how much "static pressure" it can pull (AKA: inches of Water Gage). The idea behind designing a good venturi flow in a dust collector is to get A: Laminar airflow, & B: speed up the airflow speed at the inlet (effective CFM).

Laminar airflow means that there is little or no turbulence at, or behind the inlet (the opposite of turbulent airflow). Cutting a hole in a board (and sucking air through it) will cause high instances of turbulent air flow around the inside edges of the inside of that hole, which in turn cuts the efficiency of the units effective drawing power because it is constantly fighting against that induced turbulence. Instead of abruptly focusing airflow, I like using "side panels" or shields, of some sorts, to gradually focus the airflow, so that any one given side panel is not angled more than 44 degrees relative to the direction of the airflow. For a fan(s) with good WG specs (.5 or better), a ratio of 1.5 to 1 (inlet area : fan area) down to 1 to 1 is ideal.  Gradually focusing the airflow also disperses the dust particulate more evenly over the the filter's surface. Ribbed flexible hoses should also be used only when needed, and then sparingly, as their uneven interior disrupts airflow and causes pressure drops because of the excess turbulence they produce.

Effective CFM Example: You have a 10" diameter fan (inside diameter of cowling or exit port), that can draw 600 CFM.  Its cowling or exit port "area" (area = pie * (radius squared)) is 78.5398 sq. inches.  To get an "effective" air flow speed of 600 CFM at your inlet, your "ideal" inlet opening should be about 78 sq. inches of total area, (which, BTW, is a 1:1 ratio). If however your inlet opening has 117.81 sq. in. of area, then your ratio will be 1.5 to 1, and your "effective CFM" at the inlet will only be about 400 CFM. Having an inlet area smaller than your fan(s) (exit port) area, can cause some fans to loose some of their static pressure and airflow speed, unless the fan(s) have a somewhat high static pressure specification. If you don't focus the airflow, a unit rated at 600 CFM, will act more like 200 or 300 CFM.

Why not use a filter that is about the same size of the fan, because then you wouldn't have to refocus the airflow? Well, in a perfect world it would be the ideal solution. Unfortunately, filters only come in certain "standard" sizes and shapes. And even though industrial filter lines have far more different sizes than standard filters found in hardware stores, there are still physical limitations that apply. In other words, the filter is usually the biggest thing, and everything else is designed around it. Of course a "custom made" filter would work nicely, but then you'd probably be shooting yourself in the foot as far as cost is concerned.

All the world's a stage (all you need are "good fans" to perform)

Fans capable of at least .5 inches of static pressure or better are desirable for any dust collector, but it is not the "end all be all" of fan specifications. A vacuum cleaner has very high static pressure ratings (suction power), but has nothing for CFM (airflow speed). Conversely, a standard box fan usually has a fairly reasonable CFM rating, but the static pressure ratings for these are sometimes dismal.

So, how do you choose a fan?!? Well I've always liked "tube axial" fans myself, because they usually have good static pressure ratings, high CFM, and compact design. Generally, high CFM fans (200+) of this design usually have better static pressure ratings when they have more fan blades (5 or 7), than they do with less (3). Of course, there are "dogs" out there of this variety too. Stay away from anything that looks like it may have once been used as an oscillating fan (rounded fan blades, usually white in color, shiny flexible fan blades). The better ones are the type used in mini and mainframe computers for cooling, where high airflow in a compact design is imperative (usually a black aluminum frame/cowling with mounting tabs, 5 or 7 blades, fan blades are very stiff, the outer edges of the fan blades have square corners, and come within 1/16th inch or less of the cowling).

It has been my experience that most "squirrel cage" type blowers don't have enough static pressure or air flow, until you start scaling the size up considerably. Furnace blowers are nice, but not very portable. I don't think you'll ever see a commercial "portable" bag type collector with a squirrel cage type blower that is over 1000 CFM, unless it comes with its own dolly cart.

If you happen to use a furnace blower to make a homemade dust collector, do make sure that it has ball bearings instead of sleeve bearings (some newer furnace blowers use sleeve bearings, which wear out within a couple of years).

Other Misc. Notes

Its been said "the devil is in the details". Air leaks can be like little devils, robbing your dust collector of performance and filtering effectiveness. When building or buying a dust collector, make sure it has things like filter gaskets (which keeps air flow from going around your filter), and that any air focusing panels or shields (or the main housing itself) does not have excessive gaps where air can leak through.

One thing I "hear" allot about, is the concern of how loud a dust collector will be. Unless the unit's fan(s) are unusually loud, my experience has been that if your working with a tool that requires you to run the dust collector at full speed (like a 1/4 hp flex shaft Foredom), then that tool alone will usually generate enough noise to warrant using hearing protection any ways. If, on the other hand, you are using a small micro motor tool; turning down the speed a little on most commercially available dust collectors will keep the noise levels down to a minimum, while still having enough drawing power to collect the smaller amounts of dust a tool like that generates. Other things you can do to reduce noise levels are things like not having the collectors fans within close proximity of a wall, as the wall will reflect noise. A rubber mat under bench top models will keep low frequency vibrations from being transmitted to your table top. Rubber gaskets between the fan housing and whatever it is mounted to prevents vibration from being conducted to the rest of the enclosure (and may give you a better air seal around the fans also).

When making/designing a ducted type of collector, use two 45 degree corners to take a 90 degree turn, otherwise you'll have an excessive pressure drop occur on that duct, and possibly have it clog up at that 90 degree junction. Proper grounding of PVC ducts is essential, as you don't want a static spark blowing you and your shop into dust too. Another "rule of thumb" for running air ducts is, "the bigger the better". A larger diameter pipe will have less of a pressure drop then a smaller diameter pipe of the same length. To increase airflow at the end of each duct (the point of usage), use a slightly modified pipe reducer to make the inlet opening smaller. The inlet furthest away from the actual collector (or has the most pipe in between), will generally have the weakest suction. So keep that in mind when deciding which tools should go where, and while designing the duct layout also.

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July ~ August 1999 Tool Tip

This month's topic is about pyrographic "systems", theory and application.

If you've seen all the ads out there for pyrographic systems, your probably a bit confused about what makes a good unit, and the differences between different brands.

First, a little remedial theory on how modern "wood burners" work.... The power supply: All modern units pretty much use the same principles and have similar parts to them. The heart of the unit is the transformer, which is basically a 110v to 2v step down transformer. In other words, it "transforms" a higher voltage to a much lower "usable" voltage, which is used to heat up a small nichrome element at the end of a burning pen. Although the transformer only puts out a few volts, most brands use transformers that are capable of putting out upward of 20 amperes of current. To control how much voltage and amperage a given transformer of this sort puts out, modern units employ a triac or quadrac circuit. The circuitry is similar to a dimmer switch, which runs in series with the voltage supplying the transformer to vary the voltage given to it. Originally a "reostat" was used to do this, but they have drawbacks including voltage drift due to the reostat heating up. Also, a reostat is not very safe, unless the unit uses the proper fuses to prevent short circuit conditions from causing a fire. If your circuit, transformer, and nichrome tips have been properly matched, your pen tips should heat up throughout the power supply's "range" in a fairly linear fashion. If not, it may go from running your tips from too cold to too hot in just a few degrees of the adjustment knob.

I hope by now that wattage is finally a dead issue with most people "in the know" (see Woodcarving Illustrated's "Power Carving Manual"). However, some companies still persist perpetrating dubious claims of high wattage as a marketing ploy to the new or unsuspecting potential customers. The amount of wattage any given power supply is "capable" of drawing from a wall socket is a mute point, when you consider the fact that if you were to actually get that kind of wattage to most pen tips, the tip would last about as long as a cracked light bulb (bright, but short lived). Not to mention the fact that you'd have to have a 12 or 10 gauge pen cord wire to be able to do it (rather bulky, akin to car battery cables). Any unit rated over forty watts by the manufacturer, is most likely being "rigged" by some abnormal means to get the power supply to develop that much wattage draw. Our forty watt unit, for example, can draw upwards of 70+ watts; if you dead short out the secondaries (output side) of the transformer with a big chunk of copper, but that is hardly a useful benchmark in a real world environment. In the real world, most pyrography texturing or burnishing that is done, doesn't use more than twenty-five watts out of most systems. Light texturing usually only draws about ten watts or less.The other parts of any modern pyrography unit are the pen cord, the pen body, the actual heating elements the pen tips, and how they are attached to one another.

One might think that there can't be much differences between different brands when it comes to the power cord carrying power to the pen. Actually, this can make or break a unit's ability to deliver proper heat recovery at the pen tip. The type of jacks used on each end of the cord, to even the type of insulation coating the wire, plays a big part in how much amperage is delivered to the actual pen tip itself. If the cord or modular connections used (jacks) can't deliver the amperage, it makes no difference how much wattage a given power supply is "capable" of outputting. A tell tale sign that a given unit has a deficiency in this area, is if you can feel the modular connection at the power supply (jack) warm up after a few minutes of operation. Every burner's cord will heat up to a certain extent, depending on the operating range you are using (high or low). The key is how fast the cord insulation can dissipate the heat. If you can feel the cord heat up faster on brand A than on brand B, brand A "may" actually be doing a better job of dissipating the amperage induced heat in the cord wire (if the two units are employing the same sized gauge of wire in the cord). Obviously a bigger gauged wire in the pen cord will be able to deliver more amperage to the pen. It has been my experience, to get "really good" heat recovery, the pen cord wire should be one gauge size larger than the pen tip nichrome wire being used. This is because as a rule of thumb; the more metal in the pen tip, the more power it will need from the power supply to heat up properly.

The way that the pen body and pen tips are attached, has been of some serious contention among different manufacturers for some time. Some manufacturers have for years staunchly supported using replaceable tipped pen bodies, claiming they were just as good as a fixed tip system. Although many of these companies, as recently as a few years ago, have started to offer fixed tipped pens to their customers. Why has this happened? Maybe because customers were able to see the difference in heat recovery between fixed tipped and replaceable tipped pens? Having a connector that close to a high heat source is bound to cause problems, both electrical and mechanical in nature. "Surging" and poor heat recovery occur in replaceable tipped systems after time, because of mechanical wear of the connection, which is only sped up by heat. How fast this happens depends on how hot you burn with them. While most burners out there have some sort of modular connection (jacks) in the cord, these connections have a relatively large surface area. Replaceable tipped systems out there have very little surface contact area at that particular modular connection, which makes it a bottleneck.

Okay then, now that everyone makes a fixed tipped pen, which brand of burning pen you buy is irrelevant. Right?

Wrong! If a manufacturer won't replace the tips on their fixed tipped pens after the warranty is up, it is most likely because they have used an inexpensive, but inferior, method of affixing the nichrome pen tip to the brass carrier of the pen body. This inferior method is done by first crimping the brass carrier to the nichrome tip wire, and then using a common lead and tin solder to weld the tip into the carrier. The first problem with this method is that over 370~400 degrees, the lead and tin solder detaches (melts actually) from the nichrome and/or just oxidizes away, leaving only the contacting area of the crimp to deliver the power to the pen tip. This is why you can't solder with this type of pyrography system, because lead and tin solder will bead off nichrome when the nichrome is hotter than the solder. lead and tin solder only wets/sticks to copper, brass, and a few other metals at higher temperatures. The second problem with this method is that you can't replace the tip, because it is crimped into the carrier. If it weren't it would fall out, or get pushed in, when the lead and tin solder melted. The proper way to affix a nichrome tip to a brass carrier is by using a "jeweler's grade" silver solder to weld the nichrome tip the to brass carrier. This type of solder has a melting point over 1300 degrees, and adheres to nichrome much better. This is a more expensive and more time consuming method for the manufacturer, as it does require a micro oxy blowtorch, a steady hand, and years of experience. The only drawback to using this method is that your pen bodies have to be designed, from the ground up, to handle the extremely high temperatures that a mapp gas and oxygen torch can generate (and do it repeatably, for tip replacements). So a plastic pen body is out of the question. Other things about how the internal parts of the pen are designed, manufactured, and materials used; can make a big difference how much amperage can get to the tip, as well as longevity of the pen body itself.

Okay, lets talk about the actual nichrome pen tip itself. Not to much difference here, nichrome is nichrome. Well, to some extent that is true. Some grades of nichrome do polish up better then other grades do. If your picky, it can make a difference. Our pens are highly polished from the factory, and ready to use. This is because a long time ago the owner of SMC had noticed how much smoother and easier a polished tip acted as it was used to texture various woods. Because the surface of the pen tip is very smooth, it glides through the wood easier than a non-polished tip would. Different brands use slightly different nichrome alloys, and some even use an alloy which has a good portion of cobalt in them. This can make a difference in not only how well a nichrome tip will polish up, but also its mechanical strength, and what its heat curve is like. While tip wire with cobalt in it does exhibit good mechanical strength characteristics, it has a somewhat non-linear heat curve, and it is very hard to get it to polish up as it likes to "pit" during usage. This is why I had earlier included the pen tip wire, when talking about parts of a pyrographic system that should properly be "matched". This is also why I refer to a burner as a "system", as each individual part of a given unit has to work as a system to function properly. You can use our pyrography pens and/or cords on another brand's power supply, and they will work as good as or even better than that brand's pens. But, they do work the best when using them on our power supply and cords, as each component was built as a part of a total system.

One might think that the larger and/or longer the tip wire is, the more heat recovery it will have do to its larger mass. Not as true as you might think. I even used to think this was the case myself not that long ago. The theory goes like this: Nichrome, being a natural electrical resistor, is also a natural heat resistor as well. So heat will not travel extremely fast from one part of the tip to the other. The uniformity of the pen tip (to a certain extent), and the supply of amperage it has available to it, play the biggest parts in how well a given pen tip will perform during usage.

Although a nichrome tip will seem to heat up almost instantly when you first turn on a given unit, you should be aware of a few things. When a nichrome pen tip first heats up, a good portion of the heat that it is generating is being sucked up by the brass carriers that it is attached to (replaceable or fixed tipped systems). So you should usually wait about a minute before using it, to give it a chance to "normalize" the temperature differential between the nichrome and the brass carriers. Then, if everything else is working up to snuff, the pen tip should give you good heat recovery in most situations. This particular phenomenon actually becomes more pronounced in "really efficient" pyrography systems, and should not be confused with "surging". Surging is when your pen tip goes from hot to cold, and back again, repeatedly (which is caused by a "loose", corroded, or moving connection). This phenomenon is different in that your pen tip will get a bit hotter while using it if you did not let the pen warm up properly first, but it will not cool off again until you turn down the power adjustment knob on the unit. This effect sometimes makes people mistakenly think that there is something "wrong" with a pyrography system that exhibits this property, or that the adjustment knob was moved after they started burning, or that the power line is fluctuating the voltage supplied to the power supply. Some carvers, who are used to using an inefficient pyrography system, may try to blow on the tip to cool it off right before using it when they see this is happening. That trick doesn't work on a truly efficient pyrography systems, as it will heat up the pen tip nearly as fast as you can cool it off.

One quick way to test the efficiency of a given pyrographic system is to turn the unit up to its highest setting using a blade like pen tip, and see how long it takes the tip to attain its brightest glowing red color. An efficient unit will be faster at doing that, than an inefficient unit using a similar sized pen tip. Next, using the same blade like pen tip, put the side of the pen tip (not the blade edge) onto a piece of soft wood and burn a trench with it. On a truly efficient pyrography systems, you will see the part of the pen tip that is "in the wood" dim slightly for a moment, and then get red hot again. You may need to lightly blow away the smoke this test causes, to actually see this happening. If the part of the tip that is outside the wood stays red, but the part that is in the wood does not glow red again during the test, it is a sign that there is a bottleneck somewhere between the transformer and the pen tip.

Getting the amps to the nichrome tip "efficiently" is what sets ho-hum burners apart from real performers. Amperage is king in this application! ANY bottlenecks between the output side of the transformer and the actual nichrome tip, will cause poor heat recovery performance in the tip. I like to use the analogy of sand running though a pipe, where each grain of sand is an electron. (not water, because like electricity sand would heat up the pipe when moved at a higher pressure rate, especially though bottlenecks). Imagine a three inch pipe with sand being moved though it. If the pipe then turns into a one inch pipe and back again to a three inch or even a four inch pipe, the sand after that "bottleneck" will only have the same flow rate as it did in the one inch section of the pipe (even though the pipe has gotten bigger again). If you increase the pressure pushing the sand through the pipe (similar to raising the voltage) the pipe gets hotter, especially in the one inch section. The hotter your pipe gets, the more friction it has, and this too can slow down your flow rate. So you need to have a big pipe to begin with, and not have any bottlenecks anywhere in it.

One thing that I see, every now and again, is a carver who thinks his pen isn't giving proper heat recover, but in reality they are using the pen tip improperly or has the wrong pen tip for the application. An example of this would be using "just the point" of a large skew (knife like shape) pen to draw long evenly burned lines into their carving. Obviously, you should use the whole length of the blade to do long evenly burned lines. Although even the best pyrography systems can give "near instantaneous" heat recovery, nobody has as yet come up with something that is truly instantaneous. A ball point pen can deliver ink instantaneously to a sheet of paper when you write your name, so the speed at which you make each part of each letter doesn't matter. A pyrographic writing tip, for example, cannot do the same. So you must keep the speed at which you move the tip at a constant velocity to get evenly pyrographed letters.

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January 2000 Tool Tip

An easy way to make a lateral line on fish carvings.

If you've used the #13 pen to make fish scales, you may have already figured this one out, but here it is any ways.

To make a lateral line, all you need is a stylus of some sorts. I like to use an unheated/unplugged #9 or #8 (either original style or HD, depending on the width and depth wanted) Optima 1 pen to do this, but a dead writing pen (no ink) or regular carver stylus will work just as well. You will notice that using a thinner stylus makes it easier to crush a deeper line, hence that will cause it to raise even higher. You may have to experiment a little to find what type of stylus works best for you on a given wood.

You do have to use a wood that will "uncrush" when re-hydrated. Most woods work fine, basswood is excellent at doing this. One wood that doesn't work very well is tupelo, because it's really a "gum" taken from the roots of the tree, and it stays crushed. Test how well this technique works on a scrap piece from your carving before doing it, in case the wood is unusually soft or hard (even if you've done it on that species before).

You will need to do this to the carving when it is about 1/32 to 1/16 inch thicker than when you do your fish scale pyrography on it. The thickness will depend mostly on how deep you push the stylus, and the stylus width. Using a fine stylus (approx. .032 to .041 inches wide), make the lateral line by crushing the wood down with it. You may need to go over it lightly the first few times, pressing harder each successive time until its depth is as deep as you were you want the final surface to be during scaling. Be sure to make the depth as evenly as possible. This is why I like using something like a #8 pen, as it facilitates this more easily. Again, if you use a burning pen, use it unplugged and cold (your crushing, not burning here).

After your done with that, your ready to start sanding. Sand the surface of the fish down so that the bottom of the little trench/line you just made, is flush with the rest of the surface. Be careful not to over sand. The line will still be very visible, and will "look" like it is deeper, even after you've gotten the rest of the surface flush to it. Use your fingers to "feel" when you've gotten it flush, as this will give you a truer lateral line.

Now your ready to put your scales in. You should still be able to see where the lateral line is. If not, you may have over sanded. Using a tip like our #13 pen to burn scales in (see previous tool tips), or a "scallop" fish scale tip, works fine with this technique. Using a "cupped" or fish scale "replica" style tip may cause you to over burn your carving, and negate/ruin your crushed lateral line. Obviously, using a punch or burnishing method of scaling will not work, as you'll mess up the scales when you re-hydrate the crushed lateral line. If you've ever handled a real fish before, you know that the scales on most fresh water fish don't have a very deep texture to begin with any ways.

Now your ready to bring up your lateral line using either plain tap water, or a mixture of water and isopropyl alcohol. The isopropyl and water mix is usually 50:50, and works nicely because it evaporates faster. Splash it onto the carving liberally, using a towel immediately afterwards to soak up excess liquid. You should only need to do this once or twice at the most, letting your carving dry a bit between wettings. The lateral line should re-hydrate and raise itself within an hour or less (usually within a half hour). If your lateral line did not raise enough, or not at all, you probably over sanded it.

You may have to do some light sanding of the lateral line near the back end of the each scale if it is raised too high there. Wait until your carving is fully dried (overnight) before sanding or painting it. You will notice when using this technique that going across the grain may require a thinner stylus, as the wood will be a bit harder to crush down. Using too thin of a stylus when going with the grain on a porous wood may cause some slight "splintering" of the lateral line after it is re-hydrated. Wait until it is fully dried before trying to fix it.

Again, try this technique on a scrap piece of wood from the carving "going in the same grain direction" as you will be on the carving, before doing it on your carving. This will help you gauge how deep you'll have to crush it, and how thick of a stylus to use, in order to get a satisfactory lateral line.

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October 2000 Tool Tip

Yet another way to transfer patterns to wood.

One day whilst messing around in the shop, trying my hand at paper pyrography, I accidentally picked up a scrap piece of thermal paper (a cash register receipt actually).   I put it on my table, thermal side down, and tried to get a light toasty brown on it with a shading pen.  Well, the thermal paper didn't work too well, as far as me trying to do pyrography on it, as I soon got side tracked....  When I removed it from the table, I noticed that it kind of wanted to stick to the table.  Then I noticed why....  Evidently the chemical that turns black on thermal paper, also likes to transfer onto whatever you have pressed against it.   Hmmm, I thought.....

Any ways, this eventually led me to develop a new way of transferring patterns onto wood.  Obviously, you can't use a laser printer or copier to put the pattern onto the backside of the fax paper (heated rollers), so you need to use an ink jet printer instead.   If your pattern is out of a pattern book, you'll also need a scanner.  Because fax paper comes in rolls, you'll also have to cut it to length first (which is also nice for doing long/large patterns).

Having a computerized version of a pattern is also nice, as you can use certain graphics programs to add to, or erase, parts of them.  The pattern below originally had a bunch of quilted square blocks just underneath the girls boots, running two blocks high and the length of the pattern.  BTW, this is more of a "tole painting" pattern than it is a pyrography pattern.  I'm just using it here as an example.

Original Pattern

After printing the above pattern onto the "backside" of some fax paper, I set about transferring it to a small piece of birch board using a modified #9 writing tip (end of the tip is symmetrical).  You'll want to trace the pattern lightly with your heated pen, using a low (possibly lowest) setting on your burner.  Below is the transferred pattern on my birch block (yep, I did a little burning on it already too).

Tranferred Pattern

Erasing the pattern, or parts of a pattern, was a bit more problematic at first.   An eraser doesn't work, and sandpaper is too labor intensive....  Heat from a pen, if it's high enough, will pretty much get rid of pattern lines; but that doesn't work on every part of every pattern.  The solution is to use lacquer thinner (acetone may work also), either as a wash after your done pyrographing your pattern, or with a Q-tip when "fixing" parts of a pattern prior to burning it.

You might notice that the "o" in the word "of" on the fifth line of text is missing, as well as the right side of the upper patch on her dress.  This was done on purpose.  I had originally transferred both of those items to the wood.   I just took a Q-tip and dipped it into some lacquer thinner, took off the excess so it didn't spread out too much, and used it to "erase" those two parts of the pattern.

One nifty thing about this method is that it makes the pattern sheet stick to the wood a little bit.  So as long as you don't pull the paper away from the wood, at least on one edge of the pattern, you can pick up the edge of the paper to see where you might have missed. 

Now I printed my pattern with black ink onto the backside of the fax paper.  You might try printing your pattern with a lighter color like cyan or even yellow instead, as you should be able to see what parts of the pattern you've gone over without ever having to lift up the edge of the pattern up at all (most fax paper is pretty thin stuff, and can be easily seen through).

Now if I only knew what that chemical they use to make fax paper with is (or something similar), I could fill an ink jet cartridge with it and just use an iron for really quick pattern transfers.  Please drop me a line if you happen to know the answer to that one.

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December 2000 Tool Tip

How to make fuzzy hair, for my teddy bear.

You may remember seeing the pattern below in last month's tool tip, where I discussed a new method for transferring patterns to wood.  I happen to take that same piece of wood with me to a craft show a few weeks back, and sat down to finish it.

Tranferred Pattern

I outlined most of the girl, and even the teddy bear, but then realized I hadn't thought out how I would make the bear look fuzzy (Doh!).  The picture below is what I came up with.  As this was a "direct" scan into my computer, you can't really see that the wood on the teddy is actually raised up a bit above the rest of the surface (yes, you can even feel it).

Littlegirl1a.JPG (55269 bytes)

I had heard this tip a few years back from a good customer of mine at a carving show, and after using it myself, found that it can be quite useful.  This technique is done using a #5 "Spear Point" burning pen at a medium low setting.   Each piece of "fur" is put in somewhat randomly, as you don't want a pattern to form (don't do each hair in a row).

.ph5.JPG (3820 bytes)
Photo  of #5 Spear Point pen tip

As the first graphic below illustrates, you need to use the pen with the flat/wide side of the pen tip facing your wood at a low angle of attack.  Just jab the pen tip in a little bit, not much is needed (1/32" to 1/16th")  You also need to go "with" the grain when doing this.  Also, when you cut wood with the grain, and it tends to rip up more when going one direction than it does when cutting it in the opposite direction. That is because the grain is also going downwards into the depth of the wood (so it tends to rip up more).  This is also the direction you may want to go when doing this, to get a more pronounced effect.

ph5tt1.gif (3928 bytes)

After pushing the end of the pen tip just under the surface, quickly twist your pen body 20 to 30 degrees in one direction or the other.  This helps add to the "random-ness" of your raised fur, as some will be twisted one way, and some the other way.  You might want to experiment when doing this, as you may be able to get fur that is on the side of a bear's face (for example) to be lighter or darker in some areas by just twisting your pen in only one direction in certain areas.

ph5tt2.gif (3543 bytes)

As illustrated by the the graphic below, you can get the fur to stand up more by raising the back of your pen up, so that your pen is at 40 to 50 degrees right before pulling it out.   After a bit of practice, you'll find yourself twisting, and and raising the back of the pen, at the same time.  This is perfectly normal and is how I tend to do it also.

ph5tt3.gif (3627 bytes)

You, and maybe others around you, may see how furry this technique makes your subject look, and may want to feel it (DON'T).  The picture up above had much of its fuzziness removed because I mistakenly let people around watching me feel it.  If you do feel it, do so very lightly.  A good finish on your pyrography after your done should also keep individual "hairs" from falling out (because it's fuzzy looking, people will tend to touch that part of it).  Also, if you pack up your finished work for travel, make sure nothing heavy is on top of it.

In case your wondering, the insides of the bears ears, and the patches at the end of the feet and arms, were done by just dotting the wood with the #5 pen at a 90 degree angle (a kind of pointillism).  The dress, smock, shoes, and ribbon were done using the #13 shading pen (medium), the girl's hair and socks (including stitching on her patches and teddy bear) were done using the #12 small rounded blade pen, and the pattern was outlined and dotted (eyes, dots on dress) using the new #9 modified pen tip.

 

 

January 2012 Tool Tip
Total cost of ownership (TCO)

or
( how much does that tool "really" cost?)

When people shop for tools, especially for what have been traditionally expensive tools, they tend to shop around to get the best price.  If you can get the same, or similar, tool at XYZ company for 40% less than what ABC company is selling it for, why wouldn't you?

Well....  Sometimes you have to read the fine print, and should maybe ask a few pointed questions.  Like: what is included with the tool?  What the warranty is, what does it actually cover, and for how long?   You might even want to know the cost of "out of warranty" repairs (would you be better off just buying a new one when this one has a minor problem in a few years?).  Does the manufacturer have reasonable rates for non warranty repairs?  Do they even repair them, or do they just sell replacement parts and expect you to repair it yourself?  These questions should all be asked during the buying process, if you plan to have the tool for any reasonable length of time.

For example:  Recently, I seen one of our competitors selling a similar micro motor handpiece to the Optima 2 Plus for a seemingly much lower price.   This is obviously being done to drive their competitors out of the market place, so they can then jack up the prices again later on, as all of their other handpieces are still at relatively much higher prices.  Well, low and behold, that handpiece only includes one collet ($22.00 more for a second collet), and no extra brushes ($12 more, their price).  Okay, but that only accounted for a $34 difference.  What about the rest of the price differential?  Well, the warranty on the power supply is only a year (ours is lifetime), and the warranty on the handpiece is only for six (6) months (ours is two years).  Finding their warranty on their web site proved somewhat difficult, as I ended up having to google their site for the word "warranty".   Specifically, their warranty says: "HANDPIECES – These products are under warranty for a period of SIX MONTHS from the date of original installation by the purchaser. IT DOES NOT COVER MISUSE, NORMAL BEARING, OR CARBON BRUSH WEAR."

Okay, misuse (obviously) and brush wear (considered a consumable) are understandable, nobody's warranty covers those two items.  But what about one of the main, and arguably the most expensive, components?  Bearings!  Other than brushes (again, considered a consumable), they are THE main parts of a micro motor handpiece that is going to wear, and eventually they wear out and need to be replaced.  If properly designed, with the proper lubricant, proper installation, and barring any misuse, bearings can last for thousands of hours.  They generally are not considered a "consumable" like brushes are.  So what do they mean by "normal bearing wear"?  More to the point, what do "they" consider "normal"?  I think the six month warranty speaks volumes as to what they consider "normal" bearing wear.  

Here is a simplified example, to give you an idea of what that means.   Normally, most manufacturers calculate the MTBF or "Mean Time Between Failures", which is kind of like the "worst case scenario" expected lifetime of a piece of hardware, component, or device as a whole.  Then divide that by at least two or three (possibly higher), and then use that resulting number as the basis for their warranty and/or price (again, this is a simplified example of a much more complex calculation).  That way, they do not have to replace or repair hardly any of the products that they sold in the past under warranty.  Understandable, as companies are in business to make money, and  most can't afford to replace or repair even one tenth (1/10) of their previously sold products for free.  But what this should be telling you, is that with a 6 month warranty, they assume that a significant amount of their handpiece bearings WILL START TO FAIL within at least a YEAR or two!  Hmmm, and how much do those cost you ask?   Well, just to buy the bearings and install them yourself will cost $13.35 for each bearing, and at least another $6.50 for shipping.  That's $19.85 for one bearing!   And there are four of them in each handpiece (not including the collet thrust bearing which sees little wear).  If you call them up and ask about what it would cost to have them repair it, you will probably get an "hourly rate" (usually north of $80 per hour for labor, not including parts) with no definite estimate.  In fact, it is not unusual for handpiece repair centers to charge upwards of $120 per hour for labor alone.

By the way, our costs for out of warranty repair for handpiece bearings is only $10 per bearing, plus ACTUAL shipping costs (currently $5.25 for a Priority Mail Small Flat Rate Box).  You should also note, that the warranty on our handpieces is now two (2) years (since Jan 1st 2011), which include bearings (barring misuse, abuse, or improper storage).

Well, you might be thinking that you can just buy the bearings from them, and replace them yourself, to get by much cheaper.  You'd be wrong!  In the long run, that will cost you even more.  In fact, if you call me up and ask me to send you replacement bearings, I won't sell them to you.  Wait, what? Why?!?  Well first off, to do it properly you would need at least a half dozen of each bearing size to insure that you are not putting on a bearing that is either too tight, or too loose, onto the main shaft or motor armature shaft.  The shaft OD's and bearing ID's are rated at ABEC5 standards, which are specifically +0.0000" -0.0002" tolerance.  If you force a bearing onto a shaft, you will loose most, all, or even more than the clearance inside the bearing (typically 0.0002" to 0.0005" clearance, AKA MC2 specs) and the bearing will not last very long.  Conversely, if you put a bearing onto a shaft and it is too loose of a fit, your bearing will have excessive runout, causing vibration, brinelling of the shaft and bearing race, excessive bearing wear (because you are now running the bearing beyond the runout tolerance), and if that loose bearing seizes it will cold weld itself to the shaft (ruined shaft = even more money).  I can't even get into the other methods that we use (proprietary, sorry can't talk about it ;-) to insure that the maximum possible bearing life is attained.  But to put it simply, if you do not know the exact proper methods and procedures used to install precision handpiece bearings; I can guarantee that even with the best possible bearings that money can buy, you'll most likely ruin them upon installation, or at the very least, significantly shorten their potential lifespan.

Having your handpiece repaired by a qualified professional can also head off other potential problems, before they become a real liability.  For example, if your handpiece brushes are about to wear out, and you do not change them immediately, you will dramatically shorten the lifespan of any bearing that is near the commutator ring, and possibly incur an expensive armature replacement too.  A conscientious professional will always check the brushes (even if he/she is only working on the shaft bearings), and should advise you to spring for the brushes if they need replacing, which will save you money in the long run.  If this is not spotted, and the commutator is damaged, you will go through bearings (excessive heat) and brushes (excessive wear) like a chocoholic through candy, and end up paying for an expensive new motor armature.  Unusual debris, or debris in the "wrong" places will also tip off a qualified professional that you may be doing something wrong that can dramatically shorten the lifespan of the handpiece bearings, and will advise you not to do that anymore (it might sound harsh over the phone, but remember that this guy/gal is actually trying to save you money).

Knowing all of this, your probably now asking yourself "if this is true, then why would any handpiece manufacturer allow customers to change their own bearings?".  Well first off,  they're selling you more parts, more often!   As my younger daughter would probably say... DUH!....  Either they don't know, or just don't care, about what is required to install precision bearings into a precision instrument like a micro motor tool.

Another question, a skeptic like myself might ask, is "how can you charge so much less than your competitors for bearing replacement?"  Well, we do this as a service to our customers, not as a part of the business that needs to generate a profit.   Since fewer of our handpieces need repair any ways (mostly 5 to 6 years and older is what we see), repairing handpieces is not a full time job.

So, lets compare them now shall we?   After 5 years, assuming no "in warranty" work was needed, the handpiece was properly maintained, and the equivalent "in shop" repair by the Mfg. was done.  The variability in the least number of repairs and most number of repairs assumes that, all things being equal, a significant number of bearing failures do not start happening until at least two to three times the warranty period, and that average excludes "extreme users" that use their handpieces a lot, inappropriately, or in an industrial environment (8+ hours per day).  In other words, average users.  The "<<<1" means WAY LESS than 1, or very unlikely (almost zero, this is taken from our own data).  Also, you should keep in mind that it is usually our policy to replace bearings in pairs instead of individually, as one bad bearing on a shaft will usually cause problems for the other bearing on the same shaft down the road (so it's actually cheaper to replace the so called "good bearing" then, than having to ship the unit back and forth again in a year or so for that previously "good" bearing to be replaced).  So 1 would = 1 "set" of bearings (2 bearings).  The "True Costs in 5 years" column shows both the "Least non warranty bearing repairs" average and the "Most non warranty bearing repairs" average, rounded up the the nearest whole number (which, only mathematically, doesn't actually favor us).

Manufacturer Initial Cost Warranty Least "non warranty" bearing repairs in 5 years
(Low to medium usage, well taken care of)
Most "non warranty" bearing repairs in 5 years
(Medium to High usage, some abuse)
True Costs in 5 years
(best case to worst case rounded up average) not your including shipping costs to the factory.
A (Optima 2 Plus) $209 2 years Number of repairs ranges from 0 to <<<1 (nearly zero)
Average = almost 0 (VERY unlikely to need a repair)
Number of repairs ranges from 0 to <1 (unlikely, but possible)
1 (rounded up from avg.) * $10 (Bearing price, includes labor) * 2 (1 set) + $5 (shipping) = $25.00
Expression = 1*(10*2)+5=25
Original cost + Repairs
$209 to $234
B $135 6 months Number of repairs ranges from 1~3
Average # Repairs = (2) * $13.35 (Bearing price) * 2 (1 set) + $35 * 2 (Labor) + $6.50 *2 (shipping) = $136.40
Expression = 2*((13.35*2)+35+6.5)=136.40
Number of repairs ranges from 3~5
Average # Repairs = (4) * $13.35 (Bearing price) * 2 (1 set) + $35 * 4 (Labor) + $6.50 * 4 (shipping) = $272.80
Expression = 4*((13.35*2)+35+6.5)=272.80
Original cost + Repairs
$271.40 to $407.80

Keep in mind, that even if you had the same number of repairs on one of our handpieces, your costs would still be less.  So, if you use their "number of repairs", but using "our costs for doing the repair"; the following shows two expressions for best and worst case scenarios: Best case = 2*((10*2)+5)=50 + Original Cost = $259  Worst case =  4*((10*2)+5)=100 + Original Cost = $309. 

Given, this is a conservative estimate only using our data, as we do not have access to our competitor's failure rate data.  However, knowing how manufactures determine price and warranty gives us a key insight on their expected failure rates.  Also, we called around to a few of our competitor's dealers, asking what the average lifespan was on their handpiece bearings.  The consensus we heard was about two years, and that the labor costs were usually around a minimum of $35 per repair (bearings & shipping is more). Therefore, I feel the above table should be fairly accurate given the known variables.  Keep in mind also, that there are also "certain flaws" that we are aware of in our competitor's handpiece, which we know causes most of their bearing failures (even though it may look identical to ours, it is NOT).

After comparing the "total lifetime cost of ownership" of a tool like the Optima 2 Plus, and our competitor's discounted micro motor handpiece, you should realize that "cheap handpiece" is likely to cost you much more money than you bargained for down the line.  This of course doesn't even include your downtime (what is your time worth to you?).  What is also missing from this discussion is the power supply.  Their power supplies typically have a 1 year warranty on them, and I'm guessing repair costs could possibly exceed the price of a new one.  Our power supply carries a lifetime parts and labor warranty, the most you would have to pay for is shipping to and from the factory, and it is our policy to ONLY charge actual shipping costs.

So, would you rather pay a little more up front for a micro motor handpiece that is less likely to have problems, and lower repair costs down the road, or opt for the super cheap handpiece that has a paltry warranty (an indication of poor reliability), and higher repair costs?

 

 

 

October 2015 Tool Tip
Going, Going, Gone...

or
How to prevent your pyrographic art from fading

As many pyrographers know, UV will cause their artwork to fade.   While this effect is true, UV is not the actual "direct" cause, but rather acts as a catalyst.  Once you know the actual mechanism, you can now prevent it from happening.  I have told this story to many customers over the last dozen years, so bear with me....

I had come across a discussion years ago, that took place on a popular pyrograhic list server I had frequented, about pyrography fading, and what could done to prevent it.  During the discussion, someone mentioned that when ever she used translucent oil color pencils on her burnings, they tended not to fade or fade as much as they did without it being applied.  Also, people had noticed that other materials either didn't fade (like Tauga nuts) or faded slower than basswood (like really dense woods).   Most everyone dismissed her observations, and agreed that the pigmentation of the pencils was most likely blocking the UV, hence reducing the fading effects.  For some reason, I felt that conclusion was wrong.

I then thought about how it could be that an electromagnetic wave/particle could be causing something that should inherently be chemical in nature.   It was a bit of a puzzle, and that bugged me, but I had no immediate answers.   So I filed it away in the back of my mind as something to think about or ponder.  

While doing something unrelated a few weeks later, the realization of what was happening to cause pyrography to fade hit me like the preverbal ton-o-bricks.   A quick call to a local carpenter confirmed my suspicions, and a quick google search about how ozone is created nailed down my now "working theory".

Okay, first you have to know what wood is made out of....   Basically, it is made up of cellulose, water, and air.  Even kiln dried wood has a little bit of water in it.  The amount of air in a given wood is determined by the density of its cellulose, and so on.  Air is basically made up of mostly nitrogen and about 21% oxygen, known to chemists as O2.  Now here comes the science.  UV, UV-A in particular, has just enough energy to knock electrons on and off of atoms and molecules.  How UV fades wood is indirect, in that what it does is that it turns O2 into O3.  O3 is known as a radical isotope of oxygen that is very unstable.   This instability lends its use in industrial and commercial applications as a disinfectant and a bleach.  In fact, it is even more effective at bleaching then chlorine is.

So now that we know that the UV is turning the O2 inside the wood into O3 which reacts with the pyrography burnt onto/into the wood, what can we do about it.  Well, the call to the local carpenter was to ask what he would do "exactly" if I wanted to leave the wood around my windows in its "natural" color instead of staining it.  His answer was to put down a coat of "clear stain", otherwise known as a clear finishing oil, and then put several coats of polyurethane after it had properly dried.  If the carpenter didn't put down the oil first, within a few years the wood would erupt through the polyurethane oxidized and destroyed. 

The answer is to use an oil finish to hydraulically displace the oxygen in the wood pores.  Over time oil might yellow, but at least it doesn't bleach the wood like oxygen can.  The only problem with an oil finish, is that it can darken the wood significantly, which many pyrographers don't like.  Most finishing oils are linseed based, which will definitely darken wood grain.  But there may be alternatives to linseed oil.  I myself have tried mink oil (yep, from real minks) that is normally used on leather on a piece of basswood side grain, and I noticed very little darkening of the wood.

The next step is for someone to develop an oil based product specifically made for this use, that does not darken the wood grain.


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