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 Post subject: Soundboard Repair. . . .
PostPosted: Wed Aug 03, 2011 10:46 am 
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Koa
Koa

Joined: Thu Sep 10, 2009 4:01 pm
Posts: 1858
Location: UK
Here is a brief tutorial for those who are as sloppy and careless as myself.

Bit of a nasty ding and this is after steaming multiple times. . . . .

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No idea how it happened, luckily this appeared early on in a build. 99.999% of the time they decide to make an appearance just as one is doing the final polishing.
Not to worry. Providing we have a suitable piece of Spruce we can make it all but vanish. An off cut from the soundboard is the obvious choice. If we choose the piece from the same side of the soundboard we won't have a problem with colour/reflection mismatch. It is much more difficult to execute a near invisible repair if we have to select from pieces of Spruce that do not belong to the original soundboard.
The diagram shows the shape of the patch needed - the so called rugby ball (or American football) shape. The dotted line within the patch indicates the ideal of matching a grain line - fussy but helps to fool the eye into believing we are looking at original wood.

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I use a Scalpel to carefully cut out the shape on the original soundboard.

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Now we need to cut a similar shape on our off-cut, making sure that it is a little larger than the cut on the original soundboard.

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Now it is a simple matter of transferring our patch onto the crevice we created on the soundboard. Don't flip the piece and create reflection problems. I glue with Hide and gently compress the patch into place. Clamping helps.

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Allow to dry and then scrape or sand the patch level.

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In pragmatic terms it is 'invisible'. At least it's good enough for my ageing eyes. Picking out a grain line went a long way to the success of this particular repair. I had 3 goes at this to match the grain. Sometimes it can take many more attempts than that.
Just remember: Practice on scrap.


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PostPosted: Wed Aug 03, 2011 10:58 am 
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Brazilian Rosewood
Brazilian Rosewood
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Joined: Tue Jul 05, 2005 10:53 pm
Posts: 2198
Location: Hughenden Valley, England
Michael - thanks for posting, that's very impressive. I'm off to the scrap pile to practice.

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PostPosted: Wed Aug 03, 2011 11:38 am 
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Contributing Member
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Joined: Sun Mar 06, 2011 12:04 am
Posts: 4031
First name: Chris
Last Name: Pile
City: Wichita
State: Kansas
Country: Good old US of A
Well done.

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