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Tacoma Papoose with lifting bridge...
http://mowrystrings.luthiersforum.com/forum/viewtopic.php?f=10137&t=54157
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Author:  Conor_Searl [ Mon May 17, 2021 11:52 am ]
Post subject:  Tacoma Papoose with lifting bridge...

Any creative solutions for re-gluing the bridge on this tiny guitar with very unconventional bracing and very small offset soundhole?

Author:  Chris Pile [ Mon May 17, 2021 2:51 pm ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

A stack of books? Not kidding - did it that way once or twice when nothing else would work.

Author:  jfmckenna [ Mon May 17, 2021 3:51 pm ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

Re-top it?

:D

If you have a tremendous amount of patience and some special curved and long forceps you might be able to wedge some 'go bars' under the bridge patch and clamp it from the outside. Perhaps using magnets to align them.

Author:  Tim Mullin [ Mon May 17, 2021 4:20 pm ]
Post subject:  Tacoma Papoose with lifting bridge...

Make sure the fit is perfect (as always) and use HHG. Hi clamping pressure not necessary. At least it has bridge pins to help keep it aligned.


Sent from my iPhone using Tapatalk

Author:  Pat Foster [ Mon May 17, 2021 10:21 pm ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

Like Tim says, perfect fit and HHG. Then a vacuum clamp.

Author:  profchris [ Tue May 18, 2021 3:38 am ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

Rare earth magnets are really handy for something like this.

I'd use HHG and hold the bridge in place with hand pressure until the glue grips it.

Then apply the rare earth magnets outside, taped to some card taped to the bridge, then magnets inside applied on the end of a bent stick.

Finally heat the bridge to reactivate the glue, then leave overnight before removing the magnets.

Author:  Conor_Searl [ Tue May 18, 2021 11:31 am ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

Tim Mullin wrote:
Make sure the fit is perfect (as always) and use HHG. Hi clamping pressure not necessary. At least it has bridge pins to help keep it aligned.


Sent from my iPhone using Tapatalk


Is hi clamping pressure unnecessary because of the use of HHG, or simply not necessary for regluing a bridge?

Author:  Conor_Searl [ Tue May 18, 2021 11:32 am ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

profchris wrote:
Rare earth magnets are really handy for something like this.

I'd use HHG and hold the bridge in place with hand pressure until the glue grips it.

Then apply the rare earth magnets outside, taped to some card taped to the bridge, then magnets inside applied on the end of a bent stick.

Finally heat the bridge to reactivate the glue, then leave overnight before removing the magnets.


Do you think this method could work using original tite-bond? I've never used HHG. The extra open time of tite-bond could mean not having to re-heat the bridge once magnets are in place.

Author:  Conor_Searl [ Tue May 18, 2021 11:43 am ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

Pat Foster wrote:
Like Tim says, perfect fit and HHG. Then a vacuum clamp.


Vacuum clamps are slick! I'd never looked at them too closely. That might be the perfect trick.

Author:  DanKirkland [ Wed May 19, 2021 1:50 pm ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

You have some good advice here. I've done these before, they're interesting.

Make sure the fit is perfect (100% perfect no exceptions) and use HHG or Old Brown Glue. I made a little micro go bar deck that only reached over the bridge area (like a 1x3) and would screw to the bench. That way it was super easy to get equal pressure on all parts of the bridge and to get it aligned correctly. If you want I can draw it out for you but you're pretty smart and could probably figure it out.

Author:  Conor_Searl [ Wed May 19, 2021 3:22 pm ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

DanKirkland wrote:
You have some good advice here. I've done these before, they're interesting.

Make sure the fit is perfect (100% perfect no exceptions) and use HHG or Old Brown Glue. I made a little micro go bar deck that only reached over the bridge area (like a 1x3) and would screw to the bench. That way it was super easy to get equal pressure on all parts of the bridge and to get it aligned correctly. If you want I can draw it out for you but you're pretty smart and could probably figure it out.


So the go bars are exerting pressure from the outside, but there's nothing inside?

Author:  DanKirkland [ Wed May 19, 2021 3:33 pm ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

Conor_Searl wrote:
DanKirkland wrote:
You have some good advice here. I've done these before, they're interesting.

Make sure the fit is perfect (100% perfect no exceptions) and use HHG or Old Brown Glue. I made a little micro go bar deck that only reached over the bridge area (like a 1x3) and would screw to the bench. That way it was super easy to get equal pressure on all parts of the bridge and to get it aligned correctly. If you want I can draw it out for you but you're pretty smart and could probably figure it out.


So the go bars are exerting pressure from the outside, but there's nothing inside?


Not quite. You want maybe 14-16" of space between the beam and the bridge. I used small cutoffs from tops as the pressure bars. You can drill little spots into the bar to give them something to hold onto while you place them. This way you have access to the bridge during the glue up. Sorry I wasn't more clear previously.

Author:  jfmckenna [ Wed May 19, 2021 3:38 pm ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

I think what conor is saying is that with that gobar set up there is no opposing force from the inside. That's why I was suggesting putting gobars on the inside so that when you clamp you have something to take the pressure. I'm sure it would work though. You just have to be careful applying pressure to the bridge that is not supported on the inside. I have done this before and it works. You don't get ideal clamping pressure but as mentioned a good fit with HHG is probably good enough, that with a bit of pressure even better.

It would be a PIA to get gobars inside that thing but violin makers do something similar with the sound post.

Author:  CarlD [ Wed May 19, 2021 4:21 pm ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

How about inflating a balloon inside to provide the opposing pressure to the gobars or to the Pile of books?

Author:  Conor_Searl [ Wed May 19, 2021 4:31 pm ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

jfmckenna wrote:
It would be a PIA to get gobars inside that thing but violin makers do something similar with the sound post.


This is why violin makers are the real luthiers right? beehive

Author:  phavriluk [ Wed May 19, 2021 7:24 pm ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

Nobody HAS to do any job. If OP is not experienced in this job on this sort of guitar, I think he can encourage the owner to look elsewhere without feeling bad about it. This repair is sounding like a time-and-materials job and the owner's gonna faint when he sees the bill. Or OP will have given his time away on an unprofitable job.

Author:  Tim Mullin [ Thu May 20, 2021 11:35 am ]
Post subject:  Tacoma Papoose with lifting bridge...

No need to complicate this. As stated by experienced repair folks here, HHG is recommended because (1) it’s by far the easiest glue to clean up and (2) it will literally pull a well-fitted joint together. Some classical builders would argue “no clamping required”, i.e., a “rub joint”. Some VERY LIGHT pressure can be organized in a go bar deck, without any distortion of top or bridge. No interior bars, magnets, or cauls. And once you use HHG for a bridge, you’ll never go back.


Sent from my iPhone using Tapatalk

Author:  Lou Thier [ Thu Feb 03, 2022 4:38 pm ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

2 to 3 large cam clamps from stewmac. be careful not to overtighten and pop a brace as these are some sort of fan brace or v brace if memory serves?

Author:  Hesh [ Fri Feb 04, 2022 7:24 am ]
Post subject:  Re: Tacoma Papoose with lifting bridge...

This is a very fine example of a guitar that zero thought was given to serviceability. Tacomas are not a welcome sight in our shop for this reason and others such as their acoustic bass is under braced and they don't hold up well.

Long reach clamps are an option but they also flex a lot because of the length so really snugging them down is problematic. Books as Chris said is an option too only it obscures squeeze-out clean up somewhat but no biggie.

What ever method you arrive it Connor none of them are idea and I would not trust the repair over time and we already know that the client likely didn't humidify the thing so this could happen again. I would expand the gluing surface too to within .005" of the actual perimeter foot print to keep the repair invisible but to improve the changes that this time this bridge and this guitar get along better. I also would not guarantee the repair like we usually do, this instrument is not servicable, was never engineered to have the most common repairs like a bridge reglue done to it. We can't change that.

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