Truss Rods & Scale Length

[avengers63]

What's the reasonable range of scale length that an 18" truss rod can support?

I'm thinking about doing a 26" SL eventually. I don't believe going from 25.5 to 26 would make that much of a difference, but I've read that 27" does need a longer rod, so there's got to be a limit somewhere.

Any experience or input?

[Woodenspoke]

I am not an expert by any means but I believe that you can only bend a neck so much with any length truss rod. You want to do that in the middle of your neck rather than worry about the outer edges staying under tension.

If you just play with a two way truss rod outside of the guitar you can see the results are predominately in the middle of the rod. Rods are installed either flush up or down the neck so the rod does not normally travel full length along the neck. You certainly do not want to bend a fixed neck at the heal or the glue joint may fail.

Its a matter of how much do you really need to move the neck and would making the rod longer serve any additional purpose. Between brands you find different rod lengths for the same instrument. Other than custom making your own rods the difference of 1 -2 " probably has a minimal effect on the functionally of the truss rod. But I am no expert.

Given your 27" scale lenght and a 24 fret fingerboard shows about 20.25" you still have to use an 18" rod as no 20" rod exists as far as I know.

[j. pierce]

Given your 27" scale lenght and a 24 fret fingerboard shows about 20.25" you still have to use an 18" rod as no 20" rod exists as far as I know.

I got one of these for my upcoming baritone build. Only place I've seen 20" dual action rods, (thanks to the advice of a poster here) off-the-rack, but LMI will do custom lengths. The quality on doeringer's rods doesn't seem quite as nice as the rods I've been getting from LMI, but it doesn't particularly dodgy or anything.

[SJE-Guitars]

I used an 18" hot rod in my 27" scale baritone - no problems in the slightest in terms of operations.

In my opinion any scale over 27" is when may need something more than 18" - I will be using 22" rod in my 30.5" scale build.