Truss Rod Questions (taping, Glue, And Adjusting Dual Truss Rods)

[Dave_B]

I'm just in the reading stages and have yet to saw/glue anything valuable.

Q1: When you tape over a truss rod to avoid fretboard glue, do you need to route/scrap/sand to compensate for the thickness of the tape? I've not heard it discussed, so I'm guessing, "No".

Q2: Can someone briefly explain how to adjust a neck with dual truss rods? I'm planning out a 12-string bass, and I'm not sure I can avoid them.

Thanks,

Dave

Edit: Modified topic title for clarity.

[Geo]

The thickness of the tape is probably negligible.

I would imagine that with dual truss rods, you would crank one rod a few degrees, then the other the exact same few degrees, then repeat; i.e. moving in small increments and making sure you adjust each truss rod equally. I would go in small increments so the neck doesn't twist too much.

[Mattia]

Use thin scotch tape if you must leave it in place; if you use epoxy the thickness is entirely negligible. Re: dual rods, adjust symmetrically, and/or adjust one more than the other if you need more relief on one side.

[killemall8]

Ive never heard of LEAVING the tape... I always pull it off, and never had a problem.

Why are you trying to avoid duel acting truss rods? they are no different to install, and are better.

[VesQ]

I never understood that tape thing. Are you suppose leave it or remove it. if you take it off , glue will spread right there where the tape was after you clamp fretboard.

I just use seran wrap to cover truss rod. Dont have to think complicated tape things.

[killemall8]

It wont spread if you dont slide teh fretboard all over the place... I would never leave it there, but it might not make a difference, as long as you get a nice tight glueline still...

[DC Ross]

I accidentally left the tape on one neck. It doesn't seem to make a difference

I think the OP was asking about dual (i.e. two) truss rods, not dual action.

[Dave_B]

So, for those who remove the tape, it sounds like you're only applying glue to the neck, not the fretboard. Is that correct?

And yes, I was talking about using two truss rods, not dual-action, thanks.

[Woodenspoke]

Humm seems like a conversation I never heard before. The only reason to keep glue out of the truss rod cavity is it hardens up and may effect the rods ability to move. Honestly I kinda doubt it knowing how easily titebond is chipped from metal surfaces.

I employ three methods:

1. dont add so much glue it gushes out and dont glue down the center of the rod. How hard is it to spread the glue only where you want it. With every titebond application you must glue both surfaces before you clamp (its not an option).

2. Add a wood strip and glue over it. Veneer works

3. Fill the cavity with silicon up to the top of the rod then no glue will get into the rod.

I dont use epoxy but I would assume you have to cover the rod to keep the epoxy from bonding to the rod. II would use only silicon in this application.

[killemall8]

I never apply glue to both surfaces, not matter what im gluing.

[RestorationAD]

Humm seems like a conversation I never heard before. The only reason to keep glue out of the truss rod cavity is it hardens up and may effect the rods ability to move. Honestly I kinda doubt it knowing how easily titebond is chipped from metal surfaces.

I employ three methods:

1. dont add so much glue it gushes out and dont glue down the center of the rod. How hard is it to spread the glue only where you want it. With every titebond application you must glue both surfaces before you clamp (its not an option).

2. Add a wood strip and glue over it. Veneer works

3. Fill the cavity with silicon up to the top of the rod then no glue will get into the rod.

I dont use epoxy but I would assume you have to cover the rod to keep the epoxy from bonding to the rod. II would use only silicon in this application.

+1

I cover the threaded ends of the trussrod with paraffin before installing them this keeps the threads clear of accidents.

I also use just enough silicon on the ends to fill the void. (I really don't need to chime in most times cause Spoke covers it.)

Since I use double action trussrods I do not use a veneer.

I use a small piece of Scotch tape over the end of the exposed trussrod.

The masking tape is just there to help when spreading the glue and I always remove it.

+1 With Titebond you always cover both pieces of wood. Always... I try to use the right amount of glue... not too much but cover both surfaces with a thin layer.

[WezV]

i have never covered both surfaces with glue when using titebond on anything.... just make sure i get a nice join and an even coverage of glue on 1 face, and even clamping pressue ???

what is the purpose of putting glue on both faces?

[killemall8]

I dont know, ive heard some people only put it on both... but i never have, and all my glue joints are as strong as any... My dad has also been doing that for over 50 years (glue on only one side) and the stuff thats been sitting outside in the elements for like 20 years (tables, planters that he made) all are still fine... I think its another metal voodoo thing... It doesnt make a noticeable difference.

[WezV]

fair enough - i just dont ever remember being told that bit of info... but then most people here probably have a lot more other wood working experience than me, mine is almost purely with guitars - and i think i have only ever had one joint fail (on a particulalry oily piece of bocote and i know what i should have done to solve that)

[killemall8]

MENTAL*** Not METAL... Dang edit feature

[Narcissism]

I moisten the surfaces before I glue them. My dad taught me to do that. He's been building tables and using titebond for years, and all the tables he kept are still around. The nails holding the corners together failed before the joints holding the table top together, so I'd say its worth trusting. titebond is water soluble as well... so moistening the surfaces (not soaking them, but dabbing them with a damp papertowel till they change color) may weaken it, or it may wick the glue into the wood more.

Whatever, none of my joints have failed, including the endgrain joint on my rg-rr.

[Woodenspoke]

Epoxy one side, PVA (titebond) both sides, polyurethane one side.

I will just assume none of you read magazines about general woodworking, because I am totally amazed at the response. So we are back to glue 101.

The reason to coat both side of any titebond glue joint is to avoid glue starvation. PVA bonds buy seeping into the wood fibers, epoxy does not either does many other glues. If you coat only one side with PVA, the time the glue has to adhere to the second side and absorb into the wood fibers before you crank up a clamp is minimal. So glue starvation can be the result of pressure forcing the glue out of the joint before the second side has a chance to suck up some of the glue. Starvation meaning not enough glue to form a proper bond. One of the reasons why clamping pressure should not be excessive with PVA or any other glue for that matter.

It also allows you to lightly coat both sides. I have seen people rub one side against another but that is frankly bad form.

When you coat both sides you have positive conformation glue in fully applied across the joint no matter how much squeezes out. Maybe this is why some people experience creep with titebond (only a theory not substantiated by any facts).

I have never seen anyone coat only one side of a joint with PVA, at least not that I can remember.

[WezV]

well there you go, i have been doing smething 'wrong' all these years ... and wouldnt you know it, all my guitars imploded last night

[sam_c]

We were always taught at school that you should glue PVA to PVA. They never explained it as well as Spoke did above though.

[WezV]

well a little quick reading suggests many do because they have always have or because the glue companies say so (cant find that info on the titebond website but apparently its hidden somewhere) and when people have had to do one side only there have been no issues

I can see how it would prevent a starved join - but i am not worried or embarrassed to admit i have never done it as i feel the quality of the join prep, application method and clamping technique will do a lot more to prevent glue starvation. The times i have had to pull a join apart in the first minute or two (for silly mistakes!!) both surfaces have had an even coverage of glue on them. and like i say, never had a join fail and i have not had any creep issues either

maybe i will try a few a few methods and see how much difference it makes with my techniques

[Mattia]

I apply one-sided, never had an issue. Epoxy is the one I'll ocassionally do two-sided, however, as per manufacturer's instructions (West Systems, anyway). I have never, ever had a starved glue joint, always apply glue to fresh surfaces immediately, and then 'rub' the pieces to get an even coat, and clamp. My sign I've used enough is even (minimal) squeezeout throughout.

[Our Souls inc.]

The purpose of the tape: ( according to Stew/Mac )

with the tape in place , you put the glue on the neck and spread it, when you remove the tape, you have a small ,unglued spot along the side of the TR rout. the "squeeze" should fill that clear spot, but NOT go into the rout.

I have used the tape method and not used it , I notice no real difference , the TR still adjusts on the non-taped necks. Too much glue is not your friend, too little glue is not your friend. Like alot of things in life, balance is the key to success.

Good luck and have fun !

[FireFly]

Glue, spread, clamp. I don't see an issue. For the tr, some will add Saran wrap. I use silicon around the covered parts of the tr and then I spread the glue where I want it. Works great!

[Mattia]

I moisten the surfaces before I glue them. My dad taught me to do that. He's been building tables and using titebond for years, and all the tables he kept are still around. The nails holding the corners together failed before the joints holding the table top together, so I'd say its worth trusting. titebond is water soluble as well... so moistening the surfaces (not soaking them, but dabbing them with a damp papertowel till they change color) may weaken it, or it may wick the glue into the wood more.

Whatever, none of my joints have failed, including the endgrain joint on my rg-rr.

You don't need to moisten titebond joints, but a little moisture is a good thing for polyurethane glues - kicks the cure. I'd say moistening won't help the glue wick in, more likely to prevent it wicking in (space is taken by the water).

[Woodenspoke]

I will just say you can ignore my experience or accept it frankly I dont care if you disagree. I was taught to use the glue when I started out as a professional woodworker in the 70's. Its the same advice I have read over and over in magazines devoted to general cabinetry when the subject comes up. In fact I think if you watch some of the TV shows devoted to woodworking you will see the same thing.

I am not saying your ignorant and preaching nonsense to new builders thats your choice to make. What I am saying its not a good idea if you spend 80 hours on a project and cant take the time to spread glue on an additional sq foot of wood surface. Seems the few extra minutes over 80 hrs would be a minimal addition for piece of mind. Hopefully some People will learn which is always my intention, its is never my intention to make people look stupid, they do that to themselves.

As far as water and PVA I think that is a bad idea. As Mattia pointed out Polyurethane cures using moisture so in that application use water. But I do not recommend polyurethane for guitar building as it is one of the weakest glues available. Highly overrated.

Epoxy does not bond with the wood fibers so really only one side is necessary. But I am fine with coating both side so you know you have full coverage. Better safe than sorry.