Official Luthiers Forum!

If the neck is fitting well you don't need shims!

   The neck should be tight enought that you can actually pick up the guitar, The neck should be very stable . If the neck wiggles at all you are not properly fit.
    I use wood shims that I make in the thickness sander. Use chalk and mark the block , that will tell you where you are off. no chalk you are not contacting the block.
   You want more chalk on the end of the tail as you want theneck to pull into the joint. I like my necks so the last .010 are forced into the joint by the clamp
john hall

Be prepared to spend a bit of time getting it right if its your first go at an M and T joint. Took me a month and two necks to get it right.

I cut my tenon with a router on a Woolson jig and then used chalk and sanding sticks to get the final fit right. After a few days of chalking up and sanding you start to get a feel for how adding or removing wood from different parts of the dovetail affects the fit. Hopefully youll spend alot less time getting it right!

There is a learning curve. You'll get it down about the third one and get better as you go, after that.

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http://www.dickeyguitars.com

I typically have to shim my dovetail joints as well. John is right you want a snug fit at the very bottom of the joint as the heel tends to want to pull away from the body at this point when the guitar is under string tension.

I use veneer for a shim. I laminate on a piece of veneer over the full depth and length of the dovetail tenon. Typically the joint is now to snug so I remove the excess with a sanding block.

It’s fiddly work, but you’ll get the hang of it quickly.

Don't be afraid of shims!

Making shims is easy. Grab a 3/4" - 1" piece of your favorite hardwood, stick it in your vise, and run a handplane along the edge. Use a chisel to cut it to the appropriate length.

If one shim isn't thick enough, use 2, or 3, or 4. I find doubling or tripling up on the shims much easier than starting with one overly-thick shim and having to sand or scrape it down to the perfect thickness.

I use corners off a piece of paper... it's wood, right?

I've used maple veneer for shim material which is plenty thick and will need thinning once glued on. If I go down to the original wood I will chisel of the remaining maple and re-glue another shim. Haven't done that in awhile. Knock on wood

For the fit I will clamp the neck to the body dry then after releasing the clamp I will force the neck forcing the heel away from the body if this moves. Re-shimming is in order. I like to have no play and like to have everything seated nicely.

I use carbon paper to highlight the highs and lows in the joint.

As said above the more you work with this joint the easier it becomes.

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Michael Lloyd

“I was born to ignorance, yes, and lesser poverties ...
I was born to privilege that I did not see ... I didn’t know it, but my way was paved” – John Gorka

A simple shim maker is your plane. Iron the curls straight. You can make great shims that way
john hall

im getting closer. paper is helping me find were i need to tighten it up. should i be trying to shim one side like the bass or treble or is it easier to put shims on both sides. thanks again. all of your help is really appreciated

Jeremy,
I trained as a private pilot. As I was doing my first dovetail, I realized it was like flying a plane in for a landing.

Putting shims on one side will work if it needs to move in the opposite direction.

Think of this, with a guitar body lying on the workbench, the neck must align up and down. Secondly it must align down the center, right and left. Thirdly, it must be horizontal, neither rolling to the left or right.

To land that sucker, you gotta hit all three! I'd stay away from paper and go with real wood shims. I seem to remember someone using other "approved" shim material, but it escapes me what those shims are made of. Good luck, you can do it.

If it doesn't work the first time, do a go-around and try again.

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http://www.dickeyguitars.com