Single Action Vs. Dual

[snipes2222]

Hi im wes ive been around for awhile but havnt posted much.However I have learned a great deal from all of you and come to respect many of your thoughts.In any case to my topic.

I was wondering your opinions on different truss rods.I know that Dual action rods work well because all ive used are the stew-mac hot rods but the necks ive made are not thin enough for my taste.

I would like to try say a martin style single action but wonder about stability as the newest neck im making is to be a baritone.Also I was wonderign if anyone her knows Hwere to get A 28.5 in. fretboard.The only place ive found was spendy like over 50$ and i cant even remember the name of the place.Any way thanks in advance for the help.

Wes

[Acousticraft]

IMHO single acting truss rods are adequate for most guitars. Once they are set you hardly ever need to touch them. A double acting one needs a big slot routed out although there is less effort to fit as you only need a straight slot, not a curved one as for a single acting.

I make my own truss rods which can be made very cheaply by either threading the end of a 3/16" or 5mm rod or buy a piece of threaded rod.

As for a fingerboard you could get a bass blank and cut it to suit your scale length.

[Mattia]

1) I build with CF reinforcements, so it's dual action for me all the way. They're still smaller than most Martin-style boxed truss rods (6mm / 1/4" slots only). Allied Lutherie and LMI's dual action rods are thinner than StewMac's HotRods; also remember that the rod needs to be relatively deep in the neck for it to work best; 3-4mm (1/8") is the minimum wood you want between slot and back of neck, but you also don't want a whole lot more than that. I buy the rods because I can't be bothered to learn to weld, get the tools, and spend time making them; buy 6-12 at a time and they get cheaper, too. For longer scale length instruments, I've gotten LMI-style bass rods (one welded end), had them cut down to size and re-welded.

2) Fingerboard: get a bass blank.

[snipes2222]

Thank you both for replying so quickly.I think ill have a look at allied lutherie and lmi's truss rods and see if i can make one myself i have access to tig welders and most everything at my work.As far as the fretboard im to paranoid to slot it myself so i was hoping to find someone that could make one cheaper than the one i found before.It looks like i may have to try after all.Im up for a new challenge!

[Mickguard]

Hmm....what about taking a CF kite tube and threading that and using that as a truss rod? Would it work? Is the CF too fragile?

Just wondering...

[Mattia]

Hmm....what about taking a CF kite tube and threading that and using that as a truss rod? Would it work? Is the CF too fragile?

Just wondering...

I don't think CF can be threaded and take that kind of tension (on the threads, not in compression). A local dutch maker has T-shaped CF bars with an active truss rod embedded in them that work fantastically well; I can put my full weight on the neck, no movement, and a very, very smooth, easy adjustment with a standard allen wrench simply bends/moves the entire thing, dead simple. Google Vox Humana if you want some vague-ish descriptions, and don't bother asking him if he'll sell them, 'cause he won't

[westhemann]

dual action all the way.there are several reasons to use them but #1 is they work better.

you can get a plenty thin neck with them.i just made a neck with a dual action rod 3/4" thick by thinning the back of the neck as much as was safe and thinning the fretboard the rest ofthe way...but to do that you MUST leave a volute because the rout of the rod is slightly deeper at the adjustment end to accomadate the adjustment nut.

there is no reason to rout it deeper,mattia.i lay mine right under the fingerboard..look at how a dual rod works and you will see why.it works on itself and just takes the neck with it..single action rods need depth because of how they work.

as long as you are going as thin as you can,you need to lay it right under the fingerboard.no reason to have a tree trunk for a neck when you don't have to,an extra 1/8" feels like hell when you are used to thinner necks,trust me on that.

the lmii rods ARE thinner.use them if you are worried.in reality i do not believe you can get a thinner neck with a single action rod because you have to rout the middle deeper anyway.

but ALWAYS use a volute...a nice pretty one looks good and adds all the strength you need right where you need it...just place the adjustment end exactly underneath the nut....and put the volute there as well

[spazzyone]

dual action...simply put

not only does it work well it also works in reverse (the main reason they were invented)

no upbow or backbow just total control over the neck!

and we place our's right under the board as well no problems

and we make some thin ass profiles to boot

and $50 is not bad for a long scale slotted board when you consider a high quality ebony blank cost that much with no slots or radius

[Mattia]

Wes, respectfully, even if it bends itself, the rod needs to work less if you have it deeper in the neck, BELOW the neck's bending axis. That's the only reason for it.

With any normally designed neck, though, there's no need to worry about putting it in 'deep enough'; just make sure you leave enough meat behind it. Mine are always just under the fingerboard, not like I'm routing them specially deeper...

[Mickguard]

Hmm....what about taking a CF kite tube and threading that and using that as a truss rod? Would it work? Is the CF too fragile?

Just wondering...

I don't think CF can be threaded and take that kind of tension (on the threads, not in compression).

Yes, I was thinking that....but what if you were to epoxy a couple of threaded metal bits at the end? You'd have the low-weight/high-strength benefits of CF rods, with the action of a normal trussrod. In theory, you could even make a dual-action CF rod --use CF bars for the flat piece and kite tubing for the rounded bit.

What got me interested in using CF rods, more than adding strength to the neck (although that too) was the idea that they can contribute tonally--creating a more sonically homogenous neck, or at least help to eliminate dead spots.

I sure hope you don't have to route too deep with the truss rods, because the necks I've been preparing are both routed as shallow as possible (although they'll be pretty thin and narrow).

[thegarehanman]

Mickguard, carbon fiber has nearly full elastic memory. Thus, unlike a metal rod, it cannot be bent and hold that shape while also exerting no force on the slot it's in. A single action rod would have to be cast as a curve. You could however apply that concept to a double action rod with straight members. However, your only real benefit would be in weight reduction. The lmii style truss rod(flat upper member) does a fair job of evening out the neck and warding off dead spots as it is. I doubt you'd see much improvement there, were it to be made from cf. As for threading, you could not thread it. Your idea of epoxying on threaded metal(brass I guess) ends would work just fine though. Just avoid aluminum, it doesn't like to hold threads under a great deal of sheer load.

peace,

russ

Edited December 24, 2006 by thegarehanman

[westhemann]

Wes, respectfully, even if it bends itself, the rod needs to work less if you have it deeper in the neck, BELOW the neck's bending axis.

the neck's "bending axis" moves when you thin the neck...so make the rout just deep enough for the rod,put the (thinned) fretboard on top,and thin the back as much as you feel is safe.

i leave 1/8" in maple...plus of course the volute

it works for ibanez.that's why i started profiling them like i do...ibanez uses 3 piece lams in their neck throughs with 2 way rods,thinner fretboards(little less than 3/16") and volutes...they have quite stiff yet easily adjustable necks.

[Mattia]

Wes, respectfully, even if it bends itself, the rod needs to work less if you have it deeper in the neck, BELOW the neck's bending axis.

the neck's "bending axis" moves when you thin the neck...so make the rout just deep enough for the rod,put the (thinned) fretboard on top,and thin the back as much as you feel is safe.

i leave 1/8" in maple...plus of course the volute

it works for ibanez.that's why i started profiling them like i do...ibanez uses 3 piece lams in their neck throughs with 2 way rods,thinner fretboards(little less than 3/16") and volutes...they have quite stiff yet easily adjustable necks.

I'm not sure we actually disagree, or put our truss rods in different places, reading the above

[westhemann]

oh yeah...look at that...hehe

imisread your first post and thought you meant you put an extra 1/8" below the fingerboard...like what is done with a single rod...hehe...i was thinking "why would he do that?"

[SwedishLuthier]

What got me interested in using CF rods, more than adding strength to the neck (although that too) was the idea that they can contribute tonally--creating a more sonically homogenous neck, or at least help to eliminate dead spots.

To get that your best alternative is to use laminated necks. A multi-laminate (5 pieces or more) is literaly impossible to produce dead spots. This is what my experience have taugth me anyway.

[westhemann]

What got me interested in using CF rods, more than adding strength to the neck (although that too) was the idea that they can contribute tonally--creating a more sonically homogenous neck, or at least help to eliminate dead spots.

To get that your best alternative is to use laminated necks. A multi-laminate (5 pieces or more) is literaly impossible to produce dead spots. This is what my experience have taugth me anyway.

amen...

[guitar2005]

Wes, respectfully, even if it bends itself, the rod needs to work less if you have it deeper in the neck, BELOW the neck's bending axis.

the neck's "bending axis" moves when you thin the neck...so make the rout just deep enough for the rod,put the (thinned) fretboard on top,and thin the back as much as you feel is safe.

i leave 1/8" in maple...plus of course the volute

it works for ibanez.that's why i started profiling them like i do...ibanez uses 3 piece lams in their neck throughs with 2 way rods,thinner fretboards(little less than 3/16") and volutes...they have quite stiff yet easily adjustable necks.

I like the look of a nice thick fretboard. On my current project, I'm considering using a 1/4" fretboard on which I will route a 1/16" deep channel so that the truss rod is 1/16" "in" the fretboard as opposed to fully in the neck itself.

What do you think? will it work?

This is the truss rod I'll be using: http://www.alliedlutherie.com/truss_rods.htm

[Mattia]

What got me interested in using CF rods, more than adding strength to the neck (although that too) was the idea that they can contribute tonally--creating a more sonically homogenous neck, or at least help to eliminate dead spots.

To get that your best alternative is to use laminated necks. A multi-laminate (5 pieces or more) is literaly impossible to produce dead spots. This is what my experience have taugth me anyway.

amen...

I have played (sort of) a few multi-lam neck basses that had some, though. Wood remains wood, and inherently inhomogenous compared to CF.

[westhemann]

maybe the multilam basses did not have good glue spread...it is VERY important to have good glue coverage on multi lam necks,and that includes the fretboard itself.

i do not believe those two small carbon fibre rods are more effective than a good multi lam neck.i think in one piece necks they are invaluable...

[westhemann]

by the way i played a steinberger once with all those cf reinforcements...but that guitar was just one big dead spot...

[snipes2222]

thanks for the replys, i think ill try a piece of all thread and make my own rod that way i can make it as thin as i want and hopefully still be effective.

Wes

[westhemann]

super bad idea.all thread is not suited AT ALL,plus we just discussed the fact that a 2 way lmii rod can be used in a mighty thin neck and works much better.

you are risking your neck stability to save about $20

[Mattia]

The issue is with material properties: laminating per se does not add any strength, and can only add stiffness and strength insofar as the members themselves are stiffer (use stiff wood species). Flipping a center section may change the stiffness/bending characteristics due to grain positioning to a relatively minor degree, but will mostly just help stability. I've seen no logical explanation of why it would increase stiffness simply by adding (elastic) glue.

It remains wood, which is plastic, and deforms over time under strain. Wood has memory, some more than others, and there's no foolproof way of telling what bit has what memory. CF does not, and is stiffer than the wood it replaces, and consistent along its length. It does not take a set, but inherently will remain straight, regardless. Thelack of memory effect, and the 'free' stiffness, is the reasons I like CF so much. And why I'll keep putting it (although possibly smaller sections) even in the multi-lams I do make, which will tend to be mahogany, walnut or cherry with a contrasting strip of maple and thin (mostly decorative) stripes of wenge, rosewood, or similar.

[snipes2222]

Hey,Wes I thought that the hot rod was made of all thread? thats what the last one i got looked loke,mabey im wrong and its just threaded on the end.

Wes

[westhemann]

all thread is a cheaper pot metal...truss rods are high quality steel.

technically you could use high quality steel all thread material,it does exist...but i really think you should go 2 way...it is incredibly superior in adjustability and strength