I work on about 3 guitars per month so buying expensive tools is not something I do unless it will greatly improve my effectiveness. Lately I have noticed making shims is taking me way too long and they typically come out less than acurate. I have contemplated buying or making a "luthiers friend sanding station" or getting a safe T Planer.

The shims I most often make are approx .025" for shiming neck resets, or bolt on necks(fender) for either underneath(angle) or the gap on the sides to increase the contact on the sides of the neck.

I normally use mahogany for acoustic and maple blanks for fenders. My current method is using my beltsander which has proven to be less than acurate and less than efficent. Is there a better method I could be useing. I have tried to use a hand plane but I can never get them small enough...


Any and all advice, input, and examples would be greatly appreciated.

Views: 1889

Reply to This

Replies to This Discussion

I would look into geting some utility veneer. I bought some solid Maple veneer some tine back, it's about .027" thick. Handy for all kinds of stuff.

Cool thanks Paul, I will defiantly look into that. That could be the ticket for me. 

they sell .023" mahogany veneer.  its what i bought and use to do my neck reset shims.  i used to make all my shims on my thickness sander and it took forever and wasn't cost effective.  

I use a tablesaw. How do you shave a piece of veneer into a wedge?

I use a block plane to make wedges. Veneer works very well as a starting point and it's fairly easy to taper to nothing if you start with a piece that's longer than you really need. That gives you something to hold on to as you taper it.

Edge banding (without the glue) is good for dove tail neck joints. If it's not thick enough I will glue up layers where I need the extra thickness then taper it down to fit.

Cool that gives me some options that I haven't thought of before.

For minor tweaks, you can use tape; in layers, gradually applying it to create a wedge shape. Begin with a thin strip at the bottom of the neck underside. Gradually add more, stairstepping the layers, and checking with a small straight edge to keep the taper true. It is easily reversible with naptha, and can correct the action while still keeping uniform contact. If I really need a wood shim, I take the veneer, or a uniform thin piece from a bandsaw ripping, and double-sided tape it to a known true straightedge. Then rub it on a sheet of sandpaper taped to a saw table, jointer bed, or other true surface. You will likely need naptha soaked through to loosen it from the tape, but that's a small matter. Good luck.   

For a fretboard extension wedge during a neck set, double-stick tape your piece to a larger piece of plexiglass.  Taper with a plane initially, then use the stationery sander while holding the plexiglass.  You can fit the piece by flipping it over and lining up the larger plexiglass piece with the top of the neck.


For shims i use veneer. And often super glue two pieces together. I don't taper them cause i don't have the proper tools for that. Thou i think is the proper way to shim. For the holes i use mi drill press and forstner bits. I found this is way safer for the piece. i used to break shims a lot with regular bits. I trace the shape of the neck to a larger piece of veneer. Cut it to shape with scissors, place it in the neck pocket. Trace the end open end of the neck pocket, cut it with scissors. Trace the holes using the neck screws, color the screw marks with pencil, drill the holes with forester drill press and forester bits and fine shape with belt sander. I never glue more than three veneers. Two is ok for me. If you can find veneer in several thicknesses, that's even better. You'll just have to cut and drill. Here's a pic of two of my shims. 

I imagine one of them Japanese hand saws could cut a pretty good shim 'blank' from scrap stock, then you could thickness/taper as needed with aforementioned methods and a half decent set of calipers. This way you can use material you already have or have a better choice of woods, although its not as convenient as just having some wood veneer if you can find what you like.

This can be a time consuming sideline during a dovetail neck set .. getting the shims to proper thickness.  I've used veneer, but ran out, so I've been slicing holly on my band saw into thin strips, and using my sanding flats to add taper or adjust thickness.  By adjusting the taper of the shim on the sanding flats, I can make a really tight dt joint to the point where I can put on a few strings up to tension to dial in my final neck angle.  Eliminates a lot of guesswork.  Someone mentioned that Martin used holly for dt shims because of its 'squishiness'; the holly will squish just enough so you can 'clamp' into the final fit of the dt.

I keep a box of different thickness shims handy and find two that can get the neck set in to almost flush, then do the final angle/thickness from there..cuts my time down a lot.


Ive never worked with holly and I dont think its common around here.. What woulds wood have comparible squish factor?


© 2024   Created by Frank Ford.   Powered by

Badges  |  Report an Issue  |  Terms of Service