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Hi,
I have been gluing the top braces on my first acoustic build for the last three of 4 days.
I don't have a go bar deck or dish, so I am using Cumpiano/Natleson's method, using clamps, doing them in stages.
I'm to the point of gluing down the x braces.
I have had the x braces in the clamps since 5 pm last night. It is 9:30 am now, so roughly 16 hours ago. I know the titebond usually says something like "remove clamps in two hours, no stress to the joint for 24 hours".
My question is, does the fact that the top is clamped to the arched brace constitute stress to the joint, or can I confidently remove the clamps now and move on to gluing down the tone bars?
Thanks.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Overnight is plenty. Proceed ahead.

Thanks, Barry!

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

With TB you only need clamp 20 min. I usually try for 30. Never had a prob.

I would say that joint doesn't have much stress.

New username, same Pat Mac

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Pat

Do a quick test. Glue up some 2” long brace scraps to a block and test at 1hr intervals. I think you will be surprised at how quickly this stuff takes hold. Humidity and temp do play a roll in drying times.

I give Titebond one hour. So you are fine. That slight bit of arching is not much stress at all. It's sometimes a good thing to test things your self. Glue a spare stick of spruce to a spare part of top wood, clamp it for and hour then try and break it apart. You will be quite surprised.

I like to allow titebond glue ups to stay in the clamps overnight when possible. I know it isn't always necessary. Titebond seems a little "plastic -ey" until it is fully cured, so the closer to "fully cured" the better I feel.

I have always used titebond and clamps with great success. As you indicated, the x brace does put the most stress on the glue joint, but I don't feel it is any where near enough to cause problems if glued well. So I clamp mine for an hour with cam clamps then I remove those and put a spring clamp on each end of the X. I leave those on for 24 hours or longer in cold, humid times. That frees me up to remove the cam clamps and move on. I usually get all the braces on in a day.

I should add I am also concerned with the bridge plate. I glue it last and leave the clamps on overnight. In the morning I'm good to go.

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Joe Beaver
Maker of Sawdust

Even hide glue doesn't take all that long to develop a lot of strength. In demoing HHG to a student once I planed off the surface of a brace cut off smooth and flat, and cut it into two pieces. I spread on HHG and did a 'rub' joint, simply rubbing them together to get the excess glue out. I set the piece down and we talked for a little while. About 15 minutes (!) after putting them down I clamped one part in the vice, and hit the other on the side with a hammer. I got 100% wood shear. I was surprised, let alone the student.

Beware of dry times using Titebond for gluing the bridge. First one I ever glued on first guitar slid/creeped almost 1/8". Can't remember how long I let it dry but certainly more than 2 hours and now I let dry for as along as I can wait after that experience. Just sayin'...

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Thank You and Best To All

Thinkgs like bridge plates and head plates, anything that can curl, I give overnight either with Titebond or HHG. Overnight generally means 12 hours. Fretboard gets at least 12 hours 24 is better. Bridge also 'overnight'.

Sometimes it's not about the glue joint; it's about the water that's in the glue, that is now in the wood, making it want to warp. Giving the wood time to dry out before you unclamp can be good. But yes, glue joints grab a lot quicker than we often think.