Replies to This Discussion

Permalink Reply by William H Bonney on February 10, 2013 at 5:25am

 I use truss rods in just about all my builds. Carbon fiber non adjustable and adjustable.

Permalink Reply by Michael Recchione on February 10, 2013 at 6:31am

I've only built short-scale instruments so far, with the longest body to nut distance about 12.5" - I'm guessing that's in line with your uke.  I've never used a truss rod, and never had a problem ... yet.  One of my instruments is based on a Greek baglamas, and has 6 steel strings in 3-courses, tuned Dd- AA-dd, so it takes a lot of tension. The neck on that one is maple, with a nut to body distance of about 9.5 inches.

As a data point, my store-bought, full-scale Greek bouzouki - roughly a 27" scale length, with the neck joining the body at the 17th fret, doesn't have a truss rod (most Greek bouzoukis don't, except the newest ones), and I've had no trouble with it.   It has 8 strings in 4 courses. 

Permalink Reply by Tim LaFave on February 10, 2013 at 1:09pm

If you're building a ukelele and using nylon strings, you will not need a truss rod. Indeed, many commercially built ukes do not use them. There is no where near the string tension over a short scale with nylon strings that there is with steel strings. Even with steel strings, if you use a laminate construction in your neck, you will not likely need a truss rod for any neck with three to four strings.

Permalink Reply by Howling Dick on February 11, 2013 at 12:26am

Thanks Guys for input. Just to clarify, I am building a guitar (albeit with a Uke body) and using steel strings. Body to nut is about 17.5".

Whaddayathink?

Permalink Reply by Scott aka Farmer Ted on February 11, 2013 at 1:18am

With 4 medium heavy steel strings, the neck will have about 145 lbs of string tension (more or less). Since the neck will extend from the body 17.5 inches, and considering the tension, it would be a shame to spend such efforts building an instrument and have the neck warp.

Truss rods aren't expensive, typically around $10-12 on Ebay, are relatively simple to install, and will ease your concerns about what will happen if you don't use one.

You might consider taking photos of the experience from start to finish and post them in a builder's blog, so others with similar situations can see how you worked through this challenge.

 

Cheers...I look forward to seeing the finished instrument and blog pics.

Permalink Reply by Michael Recchione on February 11, 2013 at 4:48am

Oh - sorry, I misunderstood what you were building.  I think you're about at the point where I'd start thinking about using a truss rod.  Your nut to body distance is about the same as my bouzouki, which has 8 strings and no truss rod.  But the neck is probably a little thicker (not wider, but thicker) than you'd want for a guitar.  Better safe than sorry.  I think truss rods are pretty easy to make based on what I've read, though I've never tried it.

Permalink Reply by Howling Dick on February 11, 2013 at 4:57am

Yes, Im going that way I think. Thanks!

Permalink Reply by Brent on March 28, 2013 at 2:42pm

This is a great question. I'm making my very first cbg now. I had planned on loosening the strings when not in use. I figured that would keep it from warping.

Permalink Reply by The Phrygian Kid on March 28, 2013 at 2:58pm

No you dont need one.

building a neck with a truss rod and building one without are very different things imho.

without, youre making a solid neck and saying 'im betting this bit of wood will be strong enough to handle x amount of torsion long term..'

with, youre making a neck and saying 'I acknowledge that this bit of wood is going to bend, so im cutting out even more wood to put in a counter-tensioning mechanism to correct the bowing which i know will happen..'

lot of people around here seem to think that they prevent a neck bowing.  They do not.  They correct bowing by applying counter bowing..

i think in a lot of cases the rod necessitates itself; you gotta cut quite a bit of wood right out from the core in order to fit it, thereby weakening the neck..

i'll only do em on basses or twelve strings or if someone wants a real thin 80s ibanez type profile

 

Permalink Reply by Tim LaFave on March 29, 2013 at 12:44pm

You should not need a truss rod in a three or four-string cbg - that's the whole point of building them without a full set of strings. But if you're worried, I discovered after building several, that if I find my neck stock to be slightly bowed, that's a good thing, because I invert the bow so that tension from the strings pulls the neck up straight once I tighten the strings. Works every time! Also, if you build a "laminate" neck, which you are doing to some extent if you glue on a fret board, but even more specifically if you split the neck stock and glue in a 1/4" strip of wood, or else glue wood strips to the side of the neck, you will be building a very solid neck. I have been told by guitar tech's that laminate necks are so strong ordinarily, there is no need for a trus rod in them.