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Last night I attempted to glue the back onto my sides. I wasn't happy with my go bar deck and rods as I was either getting too much pressure and denting the back or not enough pressure and not getting a good seal all the way around the body. This AFTER I had already put the glue in place. So I was trying to hurry (not a good idea) and just used 10 F clamps and cauls I had laying around instead. Checking it this morning I noticed that one or two of the clamps had slipped and there is a gap between the body and the sides about 1 1/2" long in one area and about 1/2 long in another.

After spitting out a few choice expletives I figure I've really only got one option and that is to remove the back and glue lines and start over. I don't have steaming equipment, needles etc. Suggestions as to how I can accomplish this are welcomed.

Oh btw, I immediately got online at work this morning after getting my first cup o' joe and ordered 25 luthier spool clamps as a way to prevent this from happening again. Hopefully they'll get here b4 the weekend.

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Bobby Masten

You know I did the exact same thing yesterday with my go bar deck - I had to run to the garage grad some dowels and cut them down quickly. I finally got it all buttoned up - but I notice a gap at my heel. I plan to route for the binding and look at the gap again - then my plan is to take a hot wet knife and ease it in there and then add more glue and clamp.

What kind of glue did you use ? a thin pallet knife heated and moistened should do the trick.

good luck

john

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It's this new idea from recent decades that everyone gets a participation award. - MUX

Best if you do a dry fit first next time. I've got into the habit for as may fits as possible and it's saved my hide quite a few times!

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

By the sounds of it you shouldn't need to remove the whole back. I'd use an iron directly over the gaps, warm it enough to get a knife in to remove the old glue, rub in some new glue and clamp. If the gap is at the back seem I'd do the same but with a warm knife only so as not to open the back seem. Remember that after you bind those areas will be reinforced.

Unless you used hide glue, I would remove the back and reglue. This is the only way you will get the best result.

Just use an iron and a thin knife and work you way around the top. It's not a big challenge.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Off to walmart to get an iron then...got a feeling the wife won't be happy letting me borrow hers...lol!

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Bobby Masten

This very thing happened to me, some areas were glued well, but there were little gaps where my go bars were not exerting enough pressure to push the back on the rim. I was using hide glue, which made correcting this problem very easy. All I had to do was dip a pallet knife into some hot hide glue, and fit it into the gaps, and then I could just use go bars to glue down those areas (i know this answer doesn't help out your current situation, sorry).

This is yet another reason why I like using hide glue. Of course, you have less open time than with titebond, but if you do a dry run to make sure your joints fit properly, and gently warm the pieces you are glueing, then you will not have a problem.

When glueing the plates to the rims I use a caul between the go bars and the plate. I use 1/8" material like masonite or plexi and make a caul the shape of the body and a couple of inchs wide. This will help distribute the clamping pressure and keep the go bars from leaving dents or marks in the plates. I also keep a couple pieces of 20" sq. plywood close by so I can adjust the distance between the top of the deck and the glueing surface, as part of the dry run before applying glue.

Cal

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Remember, there are no stupid questions, only stupid answers!

Here's how I do it. A masonaite 'donut' with carpet glued to it.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

If you end up having to remove a back in the future....AND you don't plan on saving the back (like in this case)...just simply route it off....

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

I would try ironing the gap areas if you have used titebond. It will melt fairly readily and enable you to clamp it together till it cools and hardens.

Thanks everyone for the tips! Used the wife's iron set on 3 (just below the steam setting) and held it for 3-4 minutes per area as I worked my thinnest scraper blade between the sides and the back. One note for next time is that if I have to do this again (probably) I'll mark where the braces are so as to not push the blade so far into the body. The ends of my top brace now have a 2" gap or so underneath them and will need to be reglued or shaved off and replaced. It took me about an hour to remove the top and hand sand off the glue lines on the back. I'll be putting the sides back in the radius dish to clean up the remaining glue and retruing it for attachment.

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Bobby Masten

Glad you made it without too much problems (as I don't consider the slight gap under the braces as real problem. I would probably remove and replace, by the way).

Live and learn I guess!

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Thanks Alain. I was considering using a little CA since under them, but if that's not a good idea then I'll just remove and replace.

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Bobby Masten

Yea, I would remove them and glue new ones. If you have a weak spot on back braces, you are bound to hear a 'crack!' (sudden gluing failure...) as soon as the guitar will get a small hit from the back; accidental punch on your knee, or something similar. If this happens, you will hate yourself for not doing what was right.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)