Psst... Ready to join TalkBass and start posting, make new friends, sell your gear, and more?  Register your free account in 30 seconds.

Routing bit decision for LMII dbl action rod

Discussion in 'Luthier's Corner' started by Basschair, Jun 10, 2005.


  1. Basschair

    Basschair .............. Staff Member Supporting Member

    Feb 5, 2004
    Stockton, Ca
    I'm at the point where I'll be routing the channel for the truss rod shortly, and am considering my options as far as bits go. Here's what LMI says as far as channel dimensions: 11/32" – 3/8" depth of slot by 1/4" wide.

    I'm semi-new to the router, though I've been able to do some nice practice cuts and cavities on scrap wood. I don't trust my bit-choosing skills just yet, so I'm wondering if you'd be willing to point me in the right direction (as far as specific bit dimensions go). The Stew Mac bit for the Hot Rod here http://www.stewmac.com/shop/Tools/Routing_bits/Router_Bit_for_Hot_Rod_Truss_Rods.html seems like it could be made to work. I'm open to suggestions, though. Thanks!
     
  2. I started using LMI TRs because they are shallower and the bit needed to cut the channel is more readily available, stewmac needs about a 7/16" bit, which you cannot buy at home depot. LMI uses a 1/4" diameter, which you can buy even at sears. That is what you need a 1/4" diameter straight bit.
     
  3. Basschair

    Basschair .............. Staff Member Supporting Member

    Feb 5, 2004
    Stockton, Ca

    Sounds good. I figured I'd go to routerbitworld and pick up a Freud, but wanted to make sure that I ordered the right bit for the job, as I'd hate to have to send it back...thanks!
     
  4. if you read the FAQ on the site it says some people use rounded bits to round the bottom of the cavity for a tighter fit. ive never heard of it being done but i imagine its pretty nice, id like to try it
     
  5. Fasoldt Basses

    Fasoldt Basses

    Mar 22, 2005
    Stevens Point, WI
    Karl Thompson, Builder (Formerly Fat Karl)
    The LMI truss rods have a threaded square stock on each end so using a round bit would require either a deeper slot, or chiseling out the ends of the channel to accomodate the square bottom of these sections.
     
  6. yeah on each end, but not in the middle. theres a rounded bottom in the middle, hence the reason the rounded bit would be more snug