How to undo a Titebond III joint.

[jtpr]

Well, now I went and done it...

I put together a box for my tongue drum last night and glued everything up tight except the top. My thinking was to tune the top and then glue it on. Of course, as these things go, I found an expert and had a conversation with him today and he said you glue the top on first and leave the bottom off. Chisel wood off the keys (tongues), flip over, listen, flip over, chisel, and so on. So, I need to get the bottom off. the sides are bird's eye maple with a 3/8" x 3/4" rabbet cut in the bottom edge. Fitted (and glued) to this is a piece of 3/4" poplar.

Any ideas on getting the piece of poplar out without ruining the bird's eye?

Jim

[tom]

Maybe put a thin kerf blade on the tablesaw, and cut around the bottom perimeter maple, just shy of the full through-cut. Then a thin handsaw to separate the two. HTH. Tom

[John Grossbohlin]

You may have to give up on the idea of removing the bottom intact... make a new one. You may be able to recut your rabbet and remove the bottom by using a router with a fence. Run the fence along the outside of the box--probably want to put a smooth layer of tape around the outside of the box so you don't scratch it up. To retain support for the router throughout the job you could leave a small tab of wood uncut along each side to hold the bottom in place. When done routing remove the bottom by cutting the tabs off with a saw and then clean up the rabbet with a chisel. The corners would also need to be cleaned up with a chisel (or the corners of the new bottom rounded).

This all seems perfectly clear to me as I write it but may need elaboration... Let me know!

John

[arw01]

High heat will cause the glue to fail and you can take it apart.

I saw this in action at a Cosman hand tool class, A french chest was mis-glued which caused it to rack. A few mintues with two heat guns and the glue allowed the piece to be removed and reclamped with fresh glue.

Rob also told us a story of a piece that was in a gallery window with no ventilation which came apart from lamination tensions.

SO if the drum is small enough to fit into the oven, I'd try about 140 degrees or so for just a few minutes.

Alan

[Toller]

Routing it out would work, but it will be very touchy. Having a box side between the fence and the bit isn't something I would want to do. Maybe if you have a bottom bearing that is smaller than the bit, you could run it against that. Yeh, that would work, it would even be fool-proof; only problem would be the round corners, but maybe you could round off the bottom to fit.

How about making up a new box out of poplar, setting the top on it, tuning the top, and tranferring the top to the real box? If that is possible, it would be much easier.

[J T]

Wed, Nov 30, 2005, 9:20am (EST-3) [e-mail] (jtpr) doth wonder: Any ideas on getting the piece of poplar out without ruining the bird's eye?

Call the 1-800 number on the back label of the glue bottle.

I wanted to unglue a joint with Titebond II a bit back. Called the number, and they recommended a heat gun. Or, putting it in an oven. Or acetone. I used a hair blower for a few minutes, then some pressure, and it popped apart, no prob.

JOAT A rolling stone gathers no moss...unless it's a hobby he does on the weekends.

[Andy Dingley]

Heat gun, be quick about it. If it's within the first day, the stuff comes apart pretty easily.

[Jane & David]

This is a great suggestion! I have run into a very similar problem that this will help with. Thanks.

But to the original poster:

Jim,

Do you have any slit drum tuning tips you'd be willing to share? I understand that shortening or thinning the tongue will raise the pitch, but how do you lower the pitch after the tongues have been cut?

Thanks, PDX David

[Charles Self]

Good. One question that comes to my mind every time someone needs to make changes in a project glued up with TB II or III or polyurethane is why they build a project intended for total indoor use with waterproof, nearly solvent proof, adhesive?

Just curious. Did TB I quit working a couple years ago? A bit of steam and that allows joint changes. I also seem to recall hearing that all the great instrument builders--Amati, Strad, et al--were stuck with using hide glue, which is readily reversible, and apparently also gives the best sound (can't tell by my ears, with 50% of my hearing gone).

I know none of that is much help in retrospect, but it seems like something others might want to think of when assembling most furniture and musical instruments...and most toys for that matter.

[Andy Dingley]

It's what they're sold.

Here in the UK they seem to have stopped selling it. Last few times I've tried to buy some, I've been fobbed off with the later versions rather than the original. As it's a rare glue round here anyway (Brits normally use white PVA) I gues this is a stockholding question.

I still use hide glue for almost all my furniture work. With a thermostatic gluepot it's easy to use and it's still one of the best gluing choices around.

[jtpr]

OK, first the good news. I put the box up on some 2x4 pieces around the edge, couple of knocks with a piece of wood and a hammer and the bottom popped out. Bad news is; I'm not overly impressed with the adhesive properties of TB III.

Anyway, I am all ears as to what you folks feel would be a better adhesive to us in this kind of construction. I don't really know what "hide glue" or a "thermostatic gluepot" is. Do you have brand names for this stuff that I could find in the states?

Thanks for all the advice, still good knowledge to have.

-Jim

[jtpr]

David,

I had a conversation with the guy at this site:

Basically he said you need to chisel/sand off little bits at a time from the hinge end of the tonge to lower the note. Then, if you go to far, take a little off the other end. You do this with the bottom off, so it's sand/chisel, flip over, play, flip over, sand/chisel, and so on. Tedious. The top and sides must be glued very tight, this is essential. Also, I read somewhere else it is a good idea to double the width of the ends. I just glued up the top last night, so I will make my first attempt at tuning tonight. I'll let you know if I find anything. If you want to converse off line about this you can email me at ryan at jimryan dot com.

-jtpr

[Frank Boettcher]

wooden Instrument makers still use hide glue because often times when making a repair on a stringed instrument you have to disassemble parts that are fine to get to the repair. My son wrecked his double bass recently and I've done a lot of research into the subject in anticipation of making the repairs. Apparently, a heated knife and a drop of alcohol will part hide glue seams.

However, you do not want to leave your wooden stringed instrument in the car, in Mississipp,i in the summer. I can assure you it will do it no good.

Frank

[Toller]

I really like the stuff that Garratt-Wade sells. Though frankly, if you box came apart that easily, you either caught it before it was fully set or did a lousy job of gluing it.

[Charles Self]

Try original Titebond, IIRC, it has the red label, while II is blue and III is green. Borden's also makes a glue that is a PVA (polyvinyl acetate) moisture resistant glue and Lee Valley sells a super version...I think it's their 2001, but my number may be off. Basically, any good quality PVA glue, usually sold as yellow glue in the U.S., listed as woodworker's or carpenter's glue (I'm trying to recall the last time I saw a carpenter glue with anything that didn't need to be squeezed out of a caulking style cartridge...anyway, doesn't matter). You can find it in brown (for walnut), yellow and tan. Use highly water resistant glues for situations where dampness is a problem, not a once a century possibility.

[Charles Self]

when

True. Same goes for your dog, wife/girlfriend/cheesecake/ice cream/mayonnaise and probably even sunglasses. But some green wood, leave it there with the windows cracked an inch, and you might well knock two months off normal drying time.

[wood_newbie]

I don't know what happened to my original post, so if this ends up being a duplicate, what can I say...

I don't know the 'pecifics of the box construction, but it sounds to me like you may have glued all your end grain to your long grain without any other mechanical joinery techniques (biscuits, dowels, splines, etc.). In that case, a hammer was probably just the right choice to make.

The general rule with glue is that, if you're gluing long grain to long grain, you have a near-bulletproof joint. If you're gluing end grain to long grain, you need other mechanical joinery if the joint will be stressed. If you're gluing end grain to end grain, you're wasting your time without something else mechanical.

Then again, this may not apply to your situation at all...

[Frank Boettcher]

Hide glue can be obtained in small quantities from a number of Lutier (repairer of wooden stringed instruments) supply houses or large music stores. I ordered some Bjorn industries #315 (gram or gel strength) hide glue from vitali imports (web search will get you there). However do some research on one of the violin or stringed instrument forums to see if it is worth it for you to fool with it. Has to be mixed, heated and used at a specific temp range (therefore the thermostatic gluepot, however a rigged double boiler and candy thermometer will get you by a small project). The benefit is reversibility at any future time, great strength and a cosmetically friendly glue line. If you don't think you need the reversibility (your current issue aside) you may not want to go through all that.

Frank

[wood_newbie]

I don't know all of the details of the construction of the box, but from your description it sounds like you had all your long grain glued to end grain.

Without anyother mechanical joinery, the hammer technique sounds to me like it would likely work every time.

The general rule with glue is that long grain to long grain is nearly bulletproof, long grain to end grain usually needs "assisting joinery" techniques if the joint will be sujbect to stesses, and end grain to end grain absolely requires it regardless.

Of course, none of this may apply to your piece at all, in which case feel free to tell me to go to hell...

[Lee Michaels]

"Charles Self" wrote

Cuz they never make mistakes??

Which, of course, creates lots of mistakes.