Truss Rod And Silicone

[MP63]

I routed a 1/4" slot and find the truss rod not so snug.

Will silicone help in a "not so snug" truss rod?

[jaycee]

How "not so snug" is it ?

what type of truss rod?

What you don't want is the truss rod turning around in the cavity.

If its a two way truss rod with squared nuts like these http://www.stewmac.com/shop/Truss_rods/Adj...Truss_Rods.html

then i would imagine if you pack the sides and glue it that would be ok.

Wait and see what others have to say but thats what I would do. Just make sure that the "whole" truss rod assembley doesn't turn around.

[MP63]

It's the Luthier's Mercantile two-way truss rod.

I has a flat top with a round bottom rod in a plastic cover (bottom only)

The side fit is the "not so snug" part.

I used a 1/4" bit and on the second pass it took more than it should.

It pulls out with ease. It is not loose where it wiggles, but it's those tiny areas that give you the buzz.

Glue paper onto the sides of the channel?

Just wanted to know what others use, as once it gets the fingerboard, it's done for good.

Thanks,

Mike

[ctlegacy]

It's the Luthier's Mercantile two-way truss rod.

I has a flat top with a round bottom rod in a plastic cover (bottom only)

The side fit is the "not so snug" part.

I used a 1/4" bit and on the second pass it took more than it should.

It pulls out with ease. It is not loose where it wiggles, but it's those tiny areas that give you the buzz.

Glue paper onto the sides of the channel?

Just wanted to know what others use, as once it gets the fingerboard, it's done for good.

Thanks,

Mike

The silicone is a great idea. I've been in the same boat as you a couple different times. Silicone is a good idea even if the truss rod fits snug. It gives a small barrier between the truss rod, and anything that will cause a noise.

Stu-Mac catalog has a little article about it.

Good luck!

[MP63]

Thanks for the experience.

I used to use the LMI truss rod that was wrapped in plastic. Worked great, but it is deeper than I wanted, so I opted for this one.

(I really liked the wrapped one, as it is completely silent and mounts snugly).

The problem is the second pass.

Even the slightest movement causes a difference in the slot.

If I go slow to get it all on the first pass, I burn the wood or worse yet, get the router off course and tear a big gouge out.

So, silicone worked good for you?

How much did you use? Just enough to cover the lower half?

I don't want that stuff going onto the fingerboard joint.

Thanks,

Mike

[WezV]

Silicone will do fine, but be carefull. If you get it on any glue surfaces or anything thats going to have a finish you will have problems latter. I prefer to have a snug fitting truss rod and keep silicone away from the guitars. I would probably pad out the channel with veneer first.

You need a sturdier router and a better router bit by the sounds of it.

[low end fuzz]

+1 for veneer (or binding is great)

[Flon Klar Guitars]

I use masking tape to pad the channel if necessary, which it usually is, since I generally overcut the channel by a few thousandths.

[JohnFi]

Never ever silicone to metal. It will rust very quickly. I'm horrified since it is common way to use silicone in truss rod.

[MiKro]

I don't like silicone for this reason. Years down the line it will discolor your wood. Silicone has oil in it and eventually it will creep to the surface.

Years ago they made these little balls to space a cabinet door panel in the mortise edges. A few years later you could see where each ball was in the face frame of the door. 

They also made a silicone mat for wood working that had little nubs all over it to act as a stable surface for hand routing. Well I used one so as not to have a body slide around while hand routing ( Pre CNC days). When I applied a finish the spots showed up even though I had sanded and cleaned the body.

This taught me not to use silicone anywhere wood is being used with a natural look.

Just my 0.02 cents .

MK

[Bizman62]

3 hours ago, MiKro said:

a silicone mat for wood working that had little nubs all over

If you're talking the non slip/anti slip mats they sell for various purposes, I've been in the belief that they actually are made of PVC and that the plastic softeners are the cause of many issues. PVC folders are known to melt the text off photocopies and laser printings - not surprising since the "ink" is actually plastic powder fastened with heat.

[MiKro]

1 hour ago, Bizman62 said:

If you're talking the non slip/anti slip mats they sell for various purposes, I've been in the belief that they actually are made of PVC and that the plastic softeners are the cause of many issues. PVC folders are known to melt the text off photocopies and laser printings - not surprising since the "ink" is actually plastic powder fastened with heat.

No I had one that was a silicone mat with little like half balls on the surface. I bought it from Woodcraft. It went into the trash after that problem showed itself.

mk

[Bizman62]

Speaking about little half balls, the ones used under numerous little things and also as bumpers for cabinet doors also contain some sort of softener that can cause issues.

One fool proof way to find out if a plastic product may react with wood or finish is smell. If the original package is a smelly, greasy bag, the contents most likely aren't any better quality. If there's no original package, sealing the thing into an alimentary grade plastic bag for overnight should reveal if there's any odour coming out of the product.

As they say, there's no smoke without fire. Equally there's no smell without a cause which in plastics usually means a softener.

[curtisa]

You guys do realise you're replying to a 14-year old thread, don't you?

No, wait...

[Bizman62]

We're not replying, we rejuvenated.

[ADFinlayson]

Nothing wrong with resurrecting an old thread, prevents duplication and shows someone has gone to the trouble of searching the forum before asking the same old question.

I've never used silicone in the truss rod channel, my rationale was that it would deaden vibration in the neck. Don't generally have the worlds tightest truss rod channels but haven't yet had a problem with rattle. I can turn the truss rod enough so that it's creating enough force on the channel to stop it moving around before it actually changes the shape of the neck. I had one channel that was particularly loose on my second or third build (I routed a 1/4' cavity but had a 6mm rod) so I just cut out a thin strip of veneer and stuff it in there was the rod before glueing up the fretboard. 

[curtisa]

OK, well seeing as we're all rejuvinating...

To get back to the thread reviver's point, there's nothing stopping you using neutral cure silicone to avoid the corrosion issue, although I've personally never heard of a truss rod failing due to rust that couldn't be traced back to severe moisture issues across the whole instrument, in which case a bit of corrosion on the rod is probably the least of your worries. There's also no reason to explicitly use silicone products either. Acrylic caulk used in kitchens and bathrooms would also be perfectly acceptable and is non-corrosive. It would also avoid any leeching of oils into the timber that @MiKro is concerned about, although again I've personally not seen that happen where a stain penetrated its way all the way through the walls of the truss rod channel to be visible on the outer surface of the neck.

If you're in the habit of using trussrods that come fully wrapped in heatshrink you can probably do away with adding dampening materials in the channel anyway. The plastic outer covering tends to prevent any of the truss rod components from being able to vibrate against themselves or within the channel. Since I started using such rods I've never bothered adding silicone to the channel (or worrying about glue squeezing in for that matter) and have not had issues with rattle or fouled truss rod operation.

Ironically the one neck I had issues with rod rattle was where I used silicone to bed in an Allied Lutherie rod, which were meant to be the gold standard for truss rod design. It was made worse by the fact that the neck itself was quite sensitive to seasonal movement, and required frequent rod adjustment. At certain times of the year the rod would be almost competely slack and would rattle like crazy. At other times I'd have to put a couple of turns on it and the rattle would disappear.

 

15 hours ago, ADFinlayson said:

I've never used silicone in the truss rod channel, my rationale was that it would deaden vibration in the neck. 

The general concensus used to be that only a few dabs of silicone along the length of the channel was necessary to prevent the truss rod rattling in the slot. I would think that unless the slot was completely swimming in the stuff, the player's hand gripping the neck would have more of an impact in damping vibrations.