Midnight in the Garden of the Good and Evil bandsaw...

[Mark A. Kane]

I recently took the time to upgrade my Jet 14" bandsaw so as to make for an enjoyable experience to use, rather than one of frustration. It's just that I rarely have the time to make the improvements to my tooling and shop that I'm constantly envisioning. I didn't have the time this time either, but I was stopped dead in my tracks after an infuriating attempt to cut tapered shims for neck resetting a'la Frank Ford's method on frets.com, as outlined in one of the articles on neck resetting. I succeeded in fabricating things that more closely resembled antlers than the elegant shims FF produced. I'd had it: now was the time and it couldn't wait. I set out on a 2-week odyssey of researching, perusing, cogitating, agonizing (over lost work time trying to get it all together) purchasing, assembling, tuning, testing, and finally, enjoying for the first time ever turning out exceedingly fine and accurate shims of the highest order (okay, that may be pushing it, but just roll with it).

This bandsaw was the first of the "big boy" toys I ever purchased. It's 1HP, sits on a nice enclosed base and cost $425 in 1991. I'd upgraded it with Cool Blocks years ago but they never seemed to do the trick. The blades always wandered, twisted, dulled &c. This time around I went "whole hog" and completely refurbished it. I bought a Kreg fence w/micro adjuster, Carter roller guides, urethane tires, two Timber Wolf silicon steel blades, a blade de-tensioning gizmo (not the Carter rig-too pricey even for one who rolls like I do), and a wheel brush to keep my new tires clean. I went the extra mile (I was on a roll in my local Woodcraft store, with credit card in hand, look the hell out) and bought a bottle of Rust Free for all the cast iron tables in my shop. The stuff is noxious in the extreme but works like a charm. (BTW, I've only allowed myself in my local Woodcraft store once in the 10 years it's been here so as to avoid temptation). 

This project consumed many more hours than I had banked on but once I bought everything nothing, not even impatient customers, was going to stop me from getting it together once and for all. I tore the machine down and rebuilt it like the Six Million Dollar Man, a most enjoyable task performed while my shop was closed, with the phone and computer and yammering sales clerks and customers silenced. Just me and my tools and my new stuff. Exquisite. Once it was all together I tuned it up and started making test cuts on a variety of woods. A little further tuning and I was ready for the project that started me down this road, namely, tapered shims for neck resetting.

I followed Frank's method exactly by squaring up a block cut to the proper dimensions for producing a number of shims at one sitting, then making the trips to the sander to establish the taper for each cut. It took about 5-6 trips to get the first shim to be of a shape I found acceptable. I made about half a dozen more with variable results, due to the freehand nature of sanding the angle, then cutting it. I stopped and thought about a way to improve the accuracy and speed by which I could produce shims and settled upon the following method. I've attached a pic.

I chose one of the shims I'd made that possessed a uniform taper. It was too thick at it's thickest to be useful as a neck shim in all but the most extreme cases, but worked perfectly for the task I envisioned for it. I marked it along it's length at various thicknesses starting with .015" and moving up in increments of .005". I dubbed it my "reference shim". I presented the square side of the block to the fence and trued up the other side with a fresh cut. Using the micro-adjuster on the Kreg fence, I shifted the fence towards the blade by the thickness of the blade (.025). I placed the block against the fence in preparation for the next cut, but inserted the reference shim between the block and the fence at the end closest to me, up to the .020" pencil mark. I pushed the block and shim through the saw and turned out the exceedingly fine and accurate shim of the highest order I bragged on earlier. Since the block was left with a tapered side, I flipped it front to back, cranked the fence over another .025" + .020" and whacked out another shim. It was a twofer! Eureka! and a victory for imbeciles the world over. Accurate and simple. No trips to the sander required. This may be the only time I've ever come close to one-upping you, Frank, but I fully expect some further refinement of this technique from you post-haste, so I'm just keeping my head down for the time being.

These first two shims were about .017 at the thick end. I puzzled over this for a moment, expecting to see .020", then realized I hadn't taken into account the set of the teeth. They were also short by about 1/4". Both issues were easily rectified by moving the fence .032" (1/32") each time for the kerf, plus whatever thickness I was cutting for the second pass. I began turning out full length, evenly tapered shims of varying thicknesses, depending on how much reference shim was inserted between the block and the fence. This method turns out matched pairs, so I marked them as such. The blade tracks so true that I had success producing shims with the thick end around .010". The blade has 6 TPI and cuts relatively coarsely. If I put on a finer blade with less set I might turn out a smoother product, but I've come to appreciate the slightly rough nature of the shims, so I don't bother to sand them. I've set 2 Martin necks so far with them and the shims possess a certain "crushability" that makes for a positive, satisfying feel while turning the clamp to seat the neck into the dovetail block. I would say the coarseness might measure a total of .002". It simply feels right.

Here is a pic of exceedingly fine and accurate shims of the highest order, and the reference shim.

[Lee Gendvilas]

Mark, thanks for the great info. I has me fired up to taking care of my bandsaw.

[Richard Bales]

Precision bandsawing is not something I ever expected until I ran across the Carter accessories.  Have yet to acquire them thinking it just might be an exercise in futility.  But your results have inspired me to go for it.  Thanks for this!

[Mark A. Kane]

I became a believer after watching some videos on the Carter website. BTW, I've ordered another blade (a Timber Wolf w/10 TPI and zero set). It will leave a finer finish, and I want to see just how far I can take this shim cutting business. The very thinnest shims that I was able to turn out took a few tries for each because of the coarseness of the cut.

I discovered another use for these shims this morning. Since I had previously made up a few dozen and marked their thicknesses on each end, I could stack several of the thinnest together on each side of the dovetail and get a fairly accurate read on the gap at the top and bottom of both sides. Then I could cut a single shim for each side. The reason for all this was that I was setting a neck in a Martin this morning that had it's neck reset incorrectly. It was overset by about .100"! and had the tallest living saddle I think I may have ever seen, about 7/16" sticking out, give or take. The kinetic energy bound up in that thing would sever a digit, I'll warrant. But I digress. I needed a shim that tapered the other way, and had to have some thickness on the thin end. It couldn't taper to zero because it needed to fill the existing space at the bottom, but get slightly thicker towards the fingerboard end. I stacked lots of shims together in various combinations and orientations until I settled on the correct size to fill the gaps. I took more time than usual for this task, but I was more interested in playing around with the possibilities the shims offer. It's one reason I'm always behind!

[Glen H]

Mark, I've got an imported 14 inch bandsaw and the blade does the same (moves left/right, in/out).  It's got the little black plastic blocks.  Do you think the Carter roller guides would make a big difference.  You did other things to your saw, but I was wondering how much improvement the guides alone would make for mine.

[Mark A. Kane]

If I were to prioritize based on money, this is what I'd do:

1. Carter guides. Without question worth the $$$

2. Urethane tires. Ensure your existing tires are glued tight to the wheels and not slipping or moving in any way, or replace them with new urethane tires.Rockler has the best price/quality. Get them here:http://www.rockler.com/product.cfm?page=5838

3. New blade or blades, if yours are dull. I'm using Timber Wolf. Woodcraft has a sale on them now.

4.From Amazon: "Big Horn 14330 Band Saw Tension Crank" $19.50. It's easy to keep track of tension by noting the crank handle position when the blade is properly tensioned. Then, when you want to loosen the blade, back the crank out exactly 3 turns and you're done. I made a sign from a 3x5 notecard indicating whether or not the blade has tension on it . It's stuck on the front with a magnet and I flip it when appropriate.

Tension the blade with the "flutter" test; remember to mark the crank location.

Adjust the guides. Cut wood.