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 Post subject: Loose back braces
PostPosted: Wed Aug 29, 2018 7:13 pm 
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Brazilian Rosewood
Brazilian Rosewood

Joined: Thu Nov 04, 2010 1:46 pm
Posts: 2124
First name: Freeman
Last Name: Keller
Focus: Build
Status: Amateur
I have a little Seagull guitar that has three loose back braces (that would be all of them) The center (which has a seam reinforcement) seems to be tight but the braces are loose on each side. Where they are let into the kerfing they seem to be tight.

I can work a pallet knife between each brace and the top so I can probably work glue into the seam without any problem. I am guessing that the original glue was AR, the tiny bits that I can see inside don't look like hide. By pressing on the back I can see the seam close so I think I can "clamp" it by putting some weight on the back. I could also order that StewMac jack that works kind of like a turn buckle, I don't want to buy the expensive scissor jack.

I see two different approaches to this. I could use hide glue, work it into the seam and hold it closed by hand until the glue gels. My HHG glue chops aren't good enough to try to get clamps in place so I would have to hold it. Also, I would be introducing HHG into the old dry AR. Cleanup would be medium easy.

Second would be to work AR into the seams and clamp with some weight on the back. Now I have new AR into the old dry stuff. Cleanup would be medium.

Suggestions?


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 Post subject: Re: Loose back braces
PostPosted: Wed Aug 29, 2018 8:00 pm 
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Brazilian Rosewood
Brazilian Rosewood

Joined: Fri Aug 19, 2005 4:02 am
Posts: 3227
Location: The Woodlands, Texas
First name: Barry
Last Name: Daniels
Don't use hide glue. It will be very hard to get the glue in place before gelling and trying to clamp it with your hands is just not feasible. Also holding it until it gels will not keep the joint closed if there is some pressure trying to open the joint.

Best bet would be to work some small pieces of sandpaper between the back and braces to rough up and clean the surfaces. Apply Titebond or fish glue into the gap. Wedge some pre-cut popsicle sticks between the back brace and a top brace. Before you raise the popsicle sticks to their maximum height place a cam clamp on the outside of the guitar directly over the sticks. Tighten things up so that you can get the brace in good contact to the back.

An option to the cam clamp on the outside of the guitar would be to place a 3/16" thick by 1" wide sstrip of hardwood on the outside of the guitar back directly over the loose brace. Clamp the strip into place with two clamps at each end of the strip, directly over the sides of the guitar. This flexed strip of wood will reinforce the back to allow some resistance to the popsicle sticks.

To keep the popsicle sticks from sliding off the top of the braces, cut a half moon shape into the ends. Good luck. The bottom brace will be a real bear.


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 Post subject: Re: Loose back braces
PostPosted: Wed Aug 29, 2018 8:01 pm 
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Cocobolo
Cocobolo
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Joined: Fri Feb 18, 2005 6:18 am
Posts: 265
Location: United States
First name: Frank
Last Name: Ford
City: Palo Alto
State: CA
Zip/Postal Code: 94301
Country: USA
Focus: Repair
Status: Professional
Aliphatic resin (Titebond) is a dandy choice for the job. Cut some popsicle or equivalent sticks to prop the braces to the top inside, then use your weights to hold the back down while the glue dries. The good news is that the bond of back braces need not be particularly strong. . .

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Frank Ford

FRETS.COM
HomeShopTech
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 Post subject: Re: Loose back braces
PostPosted: Wed Aug 29, 2018 8:04 pm 
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Brazilian Rosewood
Brazilian Rosewood

Joined: Fri Aug 19, 2005 4:02 am
Posts: 3227
Location: The Woodlands, Texas
First name: Barry
Last Name: Daniels
Oops, looks like Frank and I were posting at the same time. And I am glad we were thinking alike.


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 Post subject: Re: Loose back braces
PostPosted: Wed Aug 29, 2018 8:06 pm 
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Cocobolo
Cocobolo
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Joined: Fri Feb 18, 2005 6:18 am
Posts: 265
Location: United States
First name: Frank
Last Name: Ford
City: Palo Alto
State: CA
Zip/Postal Code: 94301
Country: USA
Focus: Repair
Status: Professional
whew - I was typing as fast as I could. . .

_________________
Cheers,

Frank Ford

FRETS.COM
HomeShopTech
FRETS.NET


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 Post subject: Re: Loose back braces
PostPosted: Wed Aug 29, 2018 8:30 pm 
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Brazilian Rosewood
Brazilian Rosewood

Joined: Fri Aug 19, 2005 4:02 am
Posts: 3227
Location: The Woodlands, Texas
First name: Barry
Last Name: Daniels
:-)


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 Post subject: Re: Loose back braces
PostPosted: Wed Aug 29, 2018 8:52 pm 
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Brazilian Rosewood
Brazilian Rosewood

Joined: Thu Nov 04, 2010 1:46 pm
Posts: 2124
First name: Freeman
Last Name: Keller
Focus: Build
Status: Amateur
Thanks guys, AR it is. Guess I need to slurp up a popsicle tonight so I have a brace for tomorrow.


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 Post subject: Re: Loose back braces
PostPosted: Thu Aug 30, 2018 11:24 am 
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Brazilian Rosewood
Brazilian Rosewood

Joined: Fri Aug 19, 2005 4:02 am
Posts: 3227
Location: The Woodlands, Texas
First name: Barry
Last Name: Daniels
You can buy a big bag of popsicle sticks at a hobby shop or craft store for cheap. That will save on having to buy larger pants. The sticks are useful for lots of other tasks in the shop.

One more recommendation: Do a dry run of your clamping setup in order to get your moves down, and also verify that this will close up the joint sufficiently.


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