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Well because I have a limited number of clamps that opens wide enough for an acoustic guitar body, I decided to glue the back on in stages. What I did is spread hide glue in one area of the side, then clamp it on, and use binding tape to clamp on the area around it, then I will wait for the glue to dry and then unclamp and spread more glue in the unglued area and keep at it. I really need a radius dish, it would make life a lot easier. I think the problem with my previous attempt was that because I tried to shape the side using the sanding stick, I put ripples into the side that caused problems when I tried to clamp the whole thing up, so I used a flat stick to level the ripples until I can get a good even fit. I was wondering does anyone make plans that gives me a complete profile of an unbent side so I can trace them onto an unbent side and cut them to shape? as I understand it many makers do this (although they do use a laser cutter or some other automated method) then just level the kerfed lining making sure not to touch the side.

What I mean about the profile of an unbent side is lets say if someone takes a completed acoustic guitar apart, and unbends the side, I would cut new sides to exactly that shape so when bent they will follow the correct contour or radius.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

If you use a mold, you can apply tape to the inside of the mold, place the mold in your radius dish, and trace your side profile with a pencil in an offset holder.

I don't get why you would mess with using HHG for attaching the back. Fish glue, epoxy and/or PVA work so well and give you plenty of time to work. I can't see that all your extra work is worth using HHG.

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

I can't seem to find fish glue and I was questioning if PVA (white glue) will work for attaching the plate to the side. I was using hide glue because it does pull joints tighter as it dries which is good... and if I screw up (like forgot to clamp one place) I can heat it up and apply more glue and clamps and it will be good.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I'd say cut yourself up some go bars and clamp it up or make some spool clamps. You are the first one I've heard of gluing on the back a little at a time.

The simplest system I've found was someone who collected these materials.

1. 3/4"-1" styrofoam insulation cut to a 1" outline of the guitar.
2. a few boards to cover all all insulation
3. a bunch of weight to place on the board (go bars would work if you are set up for that)

Then smear on hide glue, rapidly set the styro and boards on top and weight the whole thing down.

A few dry runs and you could conceivably do the whole operationin under a minute's time. Uniform pressure is placed all the way around the rim and HHG is effectively utilized.

That said, I posted a similar thread about six months ago.
I think it was titled "closing the box with hide glue" or something like that.

There was a lot of response and good input.

All in all, I settled on using titebond and haven't looked back nor was I disappointed with the results.

Good luck with however you get the job done.

Dave

I have to agree with our pals here who are not seeing the value of using HHG for gluing on a back or top IF you are not set-up to do it both quickly AND completely. And I have never heard of anyone using HHG to glue on a back in stages either which I think would be something that would result in inconsistent glue joints.

Here is a picture of the rig that Lowden uses to glue on plates with HHG. As you can see it's a one shot deal and this rig is designed so that clamping pressure will be applied all the way around as quickly as the press is lowered.

I am not saying that HHG is not a good solution for plates but I am saying that if you don't have a method to get the needed clamping in place quickly, perhaps in 30 seconds or less, go with some other glue:

You can buy Fish Glue at Lee Valley. A real alternative to HHG.

I don't like your method of staging HHG as you have described. I also believe that you need to joint your mating surfaces better than what you have described. Both methods will give you fits in trying to get a reliable joint.

But if you wish to use HHG, here's how I did it on 8 guitars before changing to FG. Remember...WITH HHG, EVERY SECOND COUNTS!!! I use a gobar deck and I make sure that the back or top fits like a glove to the lining first...it must QUICKLY drop into place with absolutely NO fiddling. EVERY SECOND COUNTS!

1) Mix your HHG a little thicker such that it can form a bead onto the linings when you apply it from a plastic squeeze bottle
2) Warm up all the glue surfaces first with a hair dryer
3) Have all of your gobars staged and close at hand
4) Slap on the top and apply gobars around the perimeter of the plate, very quickly
5) Rehearse steps 1,3 and 4 as many times needed until you can complete the sequence within 60 seconds...45 seconds is even better depending upon the room temperature.

FG, on the other hand, will make it soooo much easier. And the results and benefits are similar. Good luck

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JJ
Napa, CA
http://www.DonohueGuitars.com