Truss rod clearance.

Discussion in 'Luthier's Corner' started by Smilodon, Nov 20, 2012.

  1. Smilodon

    Smilodon Supporting Member

    Feb 18, 2012
    Hello all!

    I'm going to install a truss rod into into the bass I'm currently building, but I'm not sure how much wood I need to leave at the back of the neck.

    The truss rod is a double action rod (Those Hot rod thingys from StewMac). The rod itself is 11mm deep. As I understand it the ends will be buried into a volute and at the neck heel, so that part doesn't worry me much. What I am worried about is what happens if the neck ever develop a back bow. Then the middle of the rod will push against the rear of the neck so there must be enough wood to hold the force of the rod.

    So in short, what's the minimum ammount of wood I should leave measured from the bottom of the truss rod slot and the back of the neck?

    The neck is made from walnut and maple. (The truss rod is buried in walnut)
  2. HaMMerHeD


    May 20, 2005
    Norman, OK, USA
    I try to leave at least 1/4" of thickness behind the rod.

    That's why I use shallower rods, such as LMI and Grizzly. The hot-rods are nice, but their depth requires a thicker neck. With an LMI or Grizzly/BBG/Allied rod, I can make the neck stock (not fingerboard) 5/8" thick, while with a Stewmac rod it needs to be 3/4" thick. It's only 1/8 of an inch (~3mm), but it's enough for me to notice anyway.
  3. Smilodon

    Smilodon Supporting Member

    Feb 18, 2012
    Thanks! :)

    Another question:

    Should I glue the carbon fiber rods along their entire length or only at the ends? (Planning on using epoxy).
  4. Musiclogic

    Musiclogic Commercial User

    Aug 6, 2005
    Southwest Michigan
    Owner/Builder: HJC Customs USA, The Cool Lute, C G O
    Best to glue the rods the entire length and make sure all 3 sides are glued and snugly fit in their channels.
  5. Smilodon

    Smilodon Supporting Member

    Feb 18, 2012
    Ok. Will do! Thanks. :)

    Now I just have to remember to update my work log here on TB... :oops: