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I recently received a commission to build an electric 5 string banjo. It will have a birdseye maple top carved PRS style,a set neck also PRS style, and a 3 piece laminated neck. My problem is with the asymmetrical neck. Does anyone know the proper placement of the trussrod? I think that it should be centered at the nut and at the heel, but this would make the trussrod lie at a slight angle to the true centerline of the neck. Any help would be appreciated.

Al

As you have figured out, five string banjo necks have two "centerlines."  This causes issues, and different makers approach this whole subject in different ways, but here's how I do it.

I run the truss rod as you suggest, with it centered at the nut and at the heel.  When cutting the heel and mounting the neck, however, the centerline follows the third string.  So, you are correct that the trussrod is at a slight angle off of the other centerline of the neck, but it's dead on center of the neck itself (if that makes any sense). 

This also has the effect of placing the frets ever so slightly off-square to the body.  But, since it moves the bass side of the frets slightly towards the nut end of the neck and away from the bridge, it actually helps with bridge compensation, and keeps the bridge from being placed at the severe angle that you see on lots of banjos.

But, many other banjo makers use the center of the nut/heel line as the only centerline of the banjo, so my way isn't the only way!  It does work though.

Dave

Thanks for the help. I thought that I knew the answer to my question, but getting it confirmed by those who have "been there, done that" takes a load off of my mind.

Al

For what it's worth, on laminated, multipiece necks I run the truss rod down the very center lamination like you would on a guitar neck, but then mount the neck at a very slight angle to the body to get the third string centerline where it should be.

Dave

Sounds like a plan. I appreciate your help.

Al