[kymarto]

I will be receiving an instrument with a fairly large crack in the upper joint (a tarogato). The crack has been pinned, is stable, and does not affect the playability according to the owner (who is a tarogato virtuoso and has the largest collection of taragotok in the world). He says, however, that it does leak a bit of moisture for about the first 30 mins. of playing until the wood swells.

I'm thinking that if the crack is pinned, then I could seal it. My plan was to use a fairly soft epoxy (the quick setting kind) mixed with a bit of wood powder. Yes? No? What say ye, oh wise ones?

TIA,
Toby

 

[griff136]

Toby, I tend to use super glue for cracks in wooden instruments. I cant see any problem in your idea though. Good luck and let us know how you get on.

 

[hornfixer]

Yup, Super Glue is super.

 

[Chris Peryagh]

Superglue and then sprinkle on wood dust, clear off the excess wood dust that hasn't stuck then apply more superglue and wood dust until you've built it up well, then file it down, paper up and polish it flush with the joint surface.

 

[kymarto]

Thanks guys. I had thought that it would be easier to work with epoxy, which does not set as fast. Also I have powders used for matching color and so disguising repairs in wood flooring, that can be mixed into epoxy. Come to think of it, I have something called "bond wood epoxy", a two part putty made expressly for wood repair and reconstruction, which I use for shakuhachi flute bores. I'll bet that would be perfect

Is there any compelling reason to use superglue rather than epoxy for such a purpose? The bond wood putty is thin enough to be forced pretty deep into the crack, and is easy to work.

Apologies BTW for putting this in the sax section. Admin feel free to move it.

 

[abadcliche]

Super glue will wick much farther in to the nooks and crannies.

 

[Chris Peryagh]

... And you don't have to wait for hours before tidying it all up which you will do with epoxy.

Even though your general superglue usually has around a three second bond, that only really applies when two surfaces meet as it's a contact adhesive. When poured onto a surface or into a crack it will remain liquid for a reasonably long enough time to wick deep into it instead of setting solid the instat it's applied, so you've got plenty of time for it to do it's job and also to help it run where you want to (using a clean needle spring, screwdriver or scalpel tip) and then make it set solid by sprinkling on wood dust.

Do a few test runs on a piece of scrap wood or a scrap joint by scoring a line in it with a scriber or knife to simulate a crack (and it also helps to further gouge along an existing line of a crack when doing crack repair using superglue), then apply the superglue and spread it with a needle spring etc. and leave it to see how long it takes to harden. Then do the same thing but this time sprinkle on wood dust after you've spread the superglue around and from that you'll be able to judge how much time it gives you which is usually more than expected.

There are those unwanted incidents when superglue decides to live up to its name and have an instant bond, usually if some has got onto your fingers and you pick up a joint only to find you leave a superglue fingerprint on it! But as the joint surface hasn't been degreased, this is easy to clean up by rubbing it to push it off using the heel of an old reed or a burnisher, taking care not to damage the finish. Not so easy on a lacquered finish (unless it's greasy) but very easy to clean up on wooden bodied instruments, especially grenadilla or rosewood ones.

 

[kymarto]

Thanks for the detailed response. I will do some dry runs as you suggest. My fear was to get superglue on the body, and having it set hard and not being able to remove it. However the instrument is unlacquered rosewood, so I guess there is no real problem.

Since the crack appears to be fairly large (I've only seen pictures), I may try a composite approach: start with superglue and let it wick down, and then finish off with the wood epoxy mixed with powder to match the color. The nice thing about the epoxy putty is that you have a window of about three hourwhim which the putty is still flexible enough to shape without tearing, so that you can mold to meet the edges of the crack seamlessly, and you can even smooth to a nice finish using a bit of oil without the need to sand and polish--but I can see the wisdom of at least starting with superglue. Thanks again!

 

[Stephen Howard]

I favour the two-glue approach for larger cracks - thin superglue first for maximum penetration followed by epoxy for filling.

If you're concerned about having to clean up superglue spills, get a tube of superglue remover - works a treat. You won't generally have any problems cleaning up superglue on a wooden-bodied instrument, but it's handy stuff to have around and it can even be used on lacquered instruments.

Regards,

 

[kymarto]

Thanks Steve! Funny thing, I just found and bought a tube of glue remover a couple of hours ago. I expect to see this instrument next week and will report back. It's an old Stowasser tárogató, should be a nice instrument, so I want to make sure to do the best possible job.