Dismiss Notice

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

More Truss Rod Questions

Discussion in 'Luthier's Corner' started by andvari7, Sep 21, 2004.


  1. andvari7

    andvari7

    Aug 28, 2004
    Ennui
    My bass project is starting off really well (I've been reading, pricing and designing for about six months, and I think I have something tangible), with one small exception - the truss rod. This thing is becoming a headache.

    Since I don't want to run the risk of a Hot Rod being too short (even for a 36" scale), I'm thinking about making my own rod. For simplicity's sake, it will be a single-action rod (I know I'll have to have a channel that is deeper in the middle than at either end). And since Melvyn's book doesn't cover absolutely everything about truss rods, are there any other resources that I could use to aid me in the construction of my own rod?
     
  2. Cliff Bordwell

    Cliff Bordwell Commercial User

    Jan 6, 2004
    USA , Orlando , Florida
    Owner of CB BASSES
    LMI will make you a custom length dual action truss rod ;)
     
  3. andvari7

    andvari7

    Aug 28, 2004
    Ennui
    SWEET! This makes my day. Thank you so much.
     
  4. 5thString

    5thString

    May 5, 2004
    Hello!

    Can you please tell me who LMI is? I'm facing the same problem and I couldn't find anybody so far to help me out with that.
     
  5. andvari7

    andvari7

    Aug 28, 2004
    Ennui
  6. andvari7

    andvari7

    Aug 28, 2004
    Ennui
    Sorry for the double-post (though they are eleven days apart...), but I think I have a few more questions:
    1. I might have to go for a twin rod approach (and since I'm getting custom-built rods from LMI, I'm doing the 38" scale). Will this affect the balance in any way? I'm okay with a heavier bass, but only if it's well balanced.
    2. Which would be better in this type of setup (in terms of stability), a single action or a dual action rod (or in this case, two)?
    3. Finally, I'm concerned about the amount of wood I'm going to have to route. What other pieces of advice can you give me?
     
  7. Suburban

    Suburban

    Jan 15, 2001
    lower mid Sweden
    Why deeper in the middle? I had a "flat floor" except for the nut end, which was slightly deeper.
    I used some knowledge from David King (kingbass.com) and from Martin Koch (buildyourguitar.com), and made my own design from that.
    Simple as cough.
     
  8. tjclem

    tjclem Supporting Member Commercial User

    Jun 6, 2004
    Central Florida
    Owner and builder Clementbass
    38" scale bass? Why?...............t
     
  9. andvari7

    andvari7

    Aug 28, 2004
    Ennui
    Perhaps that wasn't a good choice of words - I meant a concave route.
    And as for the scale - why not? I've been playing on 34" scale basses for ten years, and I want to make something new and unique.
     
  10. Groove Theory

    Groove Theory Grizzly Adams DID have a beard.

    Oct 3, 2004
    The Psychiatric Ward
    Why do you need a concave route for the truss rod? I'm interested because I'll be doing the same thing here pretty soon...
     
  11. tjclem

    tjclem Supporting Member Commercial User

    Jun 6, 2004
    Central Florida
    Owner and builder Clementbass
    Are strings around for that scale? interesting idea.......t
     
  12. You should be able to get strings, email Carl Thompson or someone similar.

    I was thinking of making a similarly scaled bass a while back, however it would be my first bass and I'm told that its difficult to make a bass with that kind of length. You need everything to be a whole lot more accurate. I've personally decided to go for 900mm, about 35.4", kinda because its longer and different and because its a nice round number (so I'll get about 4 or 5 frets that'll be on a whole mm mark :p ). 38" is a long way. Get this, 3.5 weeks of lectures left, things shall begin soon.

    I swear, truss rods are the only thing I cannot understand. Does it make more sense if you just do it and care less about exactly how it works?
     
  13. andvari7

    andvari7

    Aug 28, 2004
    Ennui
    Yeah. I'm going to get custom strings, either from DR or Carl Thompson.
     
  14. Wademeister63

    Wademeister63

    Aug 30, 2004
    Denton Tx
    You only need a concave rout if you're going to use a single action truss rod. That is simply a rod bent like an L at one end with a nut on the other end that tightens against the neck and straightening the rod, which causes the neck to bend because of the concave channel. Double action truss rods are standard for electric bass and guitars and are able to bend forward or back even before they are installed. You can cut the groove for them on a table saw if you want, and it will work just fine.
     
  15. Andvari, I understand you've been designing this for awhile but have you cut a full scale pattern to see how this unusual scale is to actually hang and play? I would! I would cut it from a simple ½" MDF, put some strap buttons on it and hang it on me to see if I could even reach the lower frets. I've played a Dingwall with fanned frets at a 36" scale and even though the body was small enough to pull the headstock towards me, it was still an uncomfortable reach to the first fret AND keep my hand in the proper playing position.

    Not that I know anything more than you - it's just better to have an definitive answer to this question before the chips start to fly.
     
  16. Groove Theory

    Groove Theory Grizzly Adams DID have a beard.

    Oct 3, 2004
    The Psychiatric Ward
    Thanks! That helps out alot, I've always been confused about truss rods, just can't get it all through my skull I guess...
     
  17. bassmanatlarge

    bassmanatlarge

    Jan 30, 2003
    A single actiontruss rod works more by counteracting the string tension than trying to straighten by pushing up in the middle although it does both of these.

    A dual action truss rod does it all by pushing up in the middle.

    You can build your own up to 36" long with tools and materials available at most building supply stores.
     
  18. I've been doing some Biochem study, so my mind is in major thinking mode. Is the concave route for the single action rod hard to pull off? I'd be interested in the potential sonic differences if it wasn't for the fact A) I'm not convinced they're particularly noticable and B) it sounds like its a bit of a nuisance to pull off, depending on how uniform the route has to be. And while I'm here didn't some of the older Fender's have issues with how the compression rod reacts over time?

    The more I think, the easier it becomes, however a double rod isn't much harder to make. Whats the Martin style rod like? I've checked over at MIMF but I still don't understand exactly how it works, especially because they reckon its two-way?

    Josh D
     
  19. I've been on this trussrod project for the last 8 months or so. I've wanted to come up with my own design that I can readily make and assemble here in my shop. I also didn't want to use any of the standard approaches. I don't really understand the need for things like HotRods dual rods and it's additional weight.

    It's a very simple matter to make a single rod, dual action, truss - one that can reverse from a compression action to an "extension" type (for lack of a better word) just by turning the adjustment in the opposite direction. My approach takes ALL the stress off of the middle of the neck and transfers it to the headstock. All it takes is one simple component in the chain and you have both actions in a simpler design. It's so easy, I'm floored that no one uses it in a production setting.

    This morning, I'm completing some machine work that will bring my new design into reality. I want to get it into a neck pretty quick but I'll make sure I get pics before it gets sealed up.
     
  20. andvari7

    andvari7

    Aug 28, 2004
    Ennui
    I think I have an idea as to how I'm going to do the truss rod in my bass. I picked this info up from Carl Thompson (indirectly):
    Use a standard, Gibson-style truss rod, but route the channel a bit differently. The way Carl does it makes the channel an even thickness from the BACK of the neck. Where most truss rod channels are routed parallel to the face of the neck, and that makes the bottom of the channel taper in thickness.

    At first, I did not understand this, but I have since figured it out. Because the neck is angled (in my case, it's going to be a 1 or 2 degree angle), the route is going to be a straight line at a 1 or 2 degree angle - parallel to the fingerboard. In Carl's situation, when the neck is angled, the route is going to be slightly tapered, and parallel to the back of the instrument. If the neck were flat on a table, the route would be at a -1 or -2 degree angle.

    So, in theory, I won't have to spend an exorbitant amount of money on a truss rod - I could even make my own, were I so inclined (and since I have no mechanical experience whatsoever, I'm none too eager).