Q: Is there a problem with my neck pocket I see something in there?
A: No problem there. It's a shim often used by Haywire, Luthiers and techs for years.
It is necessary in achieving very low action. It's part of the correct process in guitar building, setups or perfect neck matching and alignment.
specifically:
If you'd like to learn more about the guitar building process
just go to HaywireCustomGuitars.com and click on BLOG for over 100 articles here:
http://www.haywirecustomguitars.com/blog.html
What is the purpose of a neck shim for a guitar?
A shim when referring to guitar builds is for a thin spacer with specific measurement particular to one guitar only. A shim for one guitar is not interchangeable with another guitar.
The standard terminology used by luthiers for a thin wedge under a bolt-on neck is a shim.
What is the purpose of a neck shim?
To adjust the angle or pitch of the neck.
Why would you need to adjust the angle or pitch of the neck?
Let’s say you replace the neck on your guitar. You install it, level the frets, re-crown, set the neck on all 4 axis, then add the two "E" strings clamp it, adjust your truss rod for proper bow, and then if notice that the height of the strings is high. You also notice that no matter how low you adjust the
saddles, the strings are still sitting way too high above the frets.It’s at that point you
need a neck shim to change the angle so you can adjust strings to your desired string height. Now, it's time measure for a shim. It's like visiting a tailor for a final fitting.
Where is a shim placed?
Under the heel of a bolt-on neck at the bottom or at the edge of the neck pocket. It's called a reverse shim at the other end of the pocket.
What can be used for shim material?
There’s a long list of materials that could be used. You could use a guitar pick, a thin piece of veneer, a business card, a thin sheet of metal, however: HVAC silver sealing tape is one of the best choices. It is preferable to use a material that can but cut to fit across the width of the neck easily, and/or layered and won't degrade with age. Shims are also sold by Fender and Stewart-MacDonald.
Is it always required to use a neck shim whenever fitting a new bolt-on neck?
No. If after installing the neck and adjusting the truss rod you see
better action possible and you can set your action with string height better then use a shim.
You will need one, because the likelihood of a new bolt-on neck fitting exactly right just doesn’t happen. It's up to us to "make it happen".
Why is a neck shim so often needed for new neck installations?
Because wood is unpredictable in how it will settle in once installed.
No two necks fit exactly the same on a body.
As long as the bolt-on neck is installed properly and has a
good, snug fit, the shim does not affect sound whatsoever.
Is it true some builders purposely put in a shim gap for tonal purposes?
Some builders do believe that the gap created by a shim actually adds in a
special tonal quality and keeps the angle correct all in one operation.
Rick Mariner-Haywire Custom Guitars, Custom Shop
A: No problem there. It's a shim often used by Haywire, Luthiers and techs for years.
It is necessary in achieving very low action. It's part of the correct process in guitar building, setups or perfect neck matching and alignment.
specifically:
If you'd like to learn more about the guitar building process
just go to HaywireCustomGuitars.com and click on BLOG for over 100 articles here:
http://www.haywirecustomguitars.com/blog.html
What is the purpose of a neck shim for a guitar?
A shim when referring to guitar builds is for a thin spacer with specific measurement particular to one guitar only. A shim for one guitar is not interchangeable with another guitar.
The standard terminology used by luthiers for a thin wedge under a bolt-on neck is a shim.
What is the purpose of a neck shim?
To adjust the angle or pitch of the neck.
Why would you need to adjust the angle or pitch of the neck?
Let’s say you replace the neck on your guitar. You install it, level the frets, re-crown, set the neck on all 4 axis, then add the two "E" strings clamp it, adjust your truss rod for proper bow, and then if notice that the height of the strings is high. You also notice that no matter how low you adjust the
saddles, the strings are still sitting way too high above the frets.It’s at that point you
need a neck shim to change the angle so you can adjust strings to your desired string height. Now, it's time measure for a shim. It's like visiting a tailor for a final fitting.
Where is a shim placed?
Under the heel of a bolt-on neck at the bottom or at the edge of the neck pocket. It's called a reverse shim at the other end of the pocket.
What can be used for shim material?
There’s a long list of materials that could be used. You could use a guitar pick, a thin piece of veneer, a business card, a thin sheet of metal, however: HVAC silver sealing tape is one of the best choices. It is preferable to use a material that can but cut to fit across the width of the neck easily, and/or layered and won't degrade with age. Shims are also sold by Fender and Stewart-MacDonald.
Is it always required to use a neck shim whenever fitting a new bolt-on neck?
No. If after installing the neck and adjusting the truss rod you see
better action possible and you can set your action with string height better then use a shim.
You will need one, because the likelihood of a new bolt-on neck fitting exactly right just doesn’t happen. It's up to us to "make it happen".
Why is a neck shim so often needed for new neck installations?
Because wood is unpredictable in how it will settle in once installed.
No two necks fit exactly the same on a body.
As long as the bolt-on neck is installed properly and has a
good, snug fit, the shim does not affect sound whatsoever.
Is it true some builders purposely put in a shim gap for tonal purposes?
Some builders do believe that the gap created by a shim actually adds in a
special tonal quality and keeps the angle correct all in one operation.
Rick Mariner-Haywire Custom Guitars, Custom Shop
