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 Post subject: Back plate poor joint
PostPosted: Wed Mar 08, 2023 12:31 pm 
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Mahogany
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Hello. Is the a way to improve a bad back joint?

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PostPosted: Wed Mar 08, 2023 12:52 pm 
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I would cut it apart and try again... [headinwall] Make sure that it looks good before you glue it.

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PostPosted: Wed Mar 08, 2023 1:24 pm 
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You can inlay a back strip into it, about 2/3rds of the backs thickness. then with the joint reinforcement on the inside you'll be good.
Then again Steve's suggestion above is pretty solid :)

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PostPosted: Wed Mar 08, 2023 1:36 pm 
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Old Growth Brazilian Rosewood
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Juan is this for an arch top or conventional acoustic?

I would cut that out and do it again regardless of what it's for, that will show in a big, not good way.

Jointing is an acquired skill of hand plane use and I've found that my own jointing game vastly improved with just a little practice on sacrifice boards. Lots of ways to do it but two things the friend who taught me to joint plates conveyed to me that really helped were, three things actually:

1). Super sharp plane and it's so important that sharpening skills really need to be in place to successfully get great joints.

2). Assuming the proper plane(s) a shift in our weight/pressure from the back of the plane to the front corresponding to where the blade is in the joint. For example if you are nearly through the weight should be on the front of the plane, just starting the cut weight on the back of the plane.

3). Link Van Cleave who taught me and he had his own woodworking TV show on the West Coast and he was also Jim Krenov's apprentice and later Link taught at Jim's school Jim taught me that we can see a bad joint with the naked eye and the idea of candling or holding to a window and such is not necessary if we have decent vision.

What makes this helpful, not having to candle is you can take a swipe and check it out right way so another swipe can come quickly if it loos lousy.

Anyway practice on some scrap the learning curve of the weight shift goes quickly, the sharpening learning curve takes a bit longer but pays off big time in time with everything else.

Hope this help.

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PostPosted: Thu Mar 09, 2023 6:47 am 
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Thank you very much for your replies and for your time!

Is an archtop, the external arch is ready and the shape is sawn. I have experience glueing flat top plates, but this 1” joint is a devil!



These users thanked the author Juan CAR for the post: Hesh (Fri Mar 10, 2023 8:09 am)
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PostPosted: Thu Mar 09, 2023 9:48 am 
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Koa
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One other thing that I learned is if your shooting board is not flat, you can swipe the edge all you want and you'll never get a good fit. So, make sure that the shooting board is flat. [:Y:]

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These users thanked the author sdsollod for the post: Pmaj7 (Thu Mar 09, 2023 10:11 am)
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PostPosted: Thu Mar 09, 2023 5:27 pm 
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Mahogany
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sdsollod wrote:
One other thing that I learned is if your shooting board is not flat, you can swipe the edge all you want and you'll never get a good fit. So, make sure that the shooting board is flat. [:Y:]

Yes, good advice, thank you.

I have sawn and redo the joint.

The archtop construction is a true challenge!


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PostPosted: Thu Mar 09, 2023 10:05 pm 
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Hesh wrote:

<snip>

2). Assuming the proper plane(s) a shift in our weight/pressure from the back of the plane to the front corresponding to where the blade is in the joint. For example if you are nearly through the weight should be on the front of the plane, just starting the cut weight on the back of the plane.

<snip>


Interesting, Hesh. Just the opposite of what I do.

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These users thanked the author Pat Foster for the post: Hesh (Fri Mar 10, 2023 8:09 am)
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PostPosted: Fri Mar 17, 2023 8:59 am 
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Front to back weight shift….me too Pat.


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