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Mat Roop Senior Member
Joined: 24 Mar 2007 Posts: 911 Location: Wyoming Ontario
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Posted: Sun Jun 25, 2017 9:33 am Post subject: split repair |
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So I have this idea...
a long split repair needs a multitude of cleats... they are an obvious add-on with added on weight.
post and bar splits need carved patches.... very time consuming
what would be wrong with a matching set of router style bits one convex the other concave to create a divot and a perfectly matching counter button to fit the divot?
That would create a neat fix, not add wood, and look professional.... and be quick to complete.
Thoughts? good idea or bad??
Cheers, Mat |
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FiddleDoug Member
Joined: 08 Sep 2007 Posts: 227 Location: Hilton, NY
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Posted: Sun Jun 25, 2017 12:28 pm Post subject: Bad Idea |
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Bad Idea! Generally, removing wood is worse than adding wood. Adding wood cleats is reversible, cutting divots isn't. Soundpost patches are an exception, as they deal with point pressure from the soundpost, and the hinging action created. Bass bar cracks don't require carved patches, just cleats under the bass bar. Also, every time that you cut into the plate, the cavity has endgrain that you're gluing against. Gluing to endgrain is the weakest kind of joint. As far as "looking professional", the only people that are likely to see it are other luthiers, and the general consensus might be for them to say "What hack cut divots into the plate of this instrument."
I can comment knowingly on this, because I have an instrument that someone inlaid cleats into, and when this was shown to a very fine restorer, he shook his head, and said basically that. _________________ Doug Wall
www.wallindependent.com |
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Mat Roop Senior Member
Joined: 24 Mar 2007 Posts: 911 Location: Wyoming Ontario
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Posted: Sun Jun 25, 2017 3:45 pm Post subject: |
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Thanks Doug... good points! ... especially the end grain issue for strength.
I guess some brainwaves can be bad ideas:)
Cheers, Mat |
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L P Reedy Super Member
Joined: 02 Apr 2009 Posts: 276 Location: Brevard, NC
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Posted: Sun Jun 25, 2017 3:56 pm Post subject: |
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In addition to what Doug said, the weight of well-made cleats is extremely small. But possibly more important is the fact that a spinning bit cannot cut in the very center. If you don't believe that, try it. When you wet the cut you will find a little bump. Unless you were to wet both pieces and manually trim off those bumps, you would have imperfectly-fitting cleats. |
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Michael Darnton Moderator
Joined: 23 Mar 2007 Posts: 1286 Location: Chicago
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Posted: Tue Jul 18, 2017 9:21 am Post subject: |
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Mat, in the restoration business ANY removal of original wood is usually considered near-butchery. It's becoming more common in restoration even to avoid soundpost patches for this reason--the tendency is to glue it up skillfully and see if it sticks, and often it will.
I cringe any time I see someone inventing a fancy new tool or technique designed to remove original wood when there are so many ways to do the job well without that. Any time you put in new wood you run the risk of near-inevitability that the new wood and old are going to move at different rates at some point, that something will happen to telegraph the presence of new wood out to the surface, and that this damage will now never be able to be reversed.
I have seen some incredibly clever repairs (for their time) go horribly wrong simply because of this fact, usually when the instrument is taken to a different climate than where the repair was done. _________________ new blog at my site! http://darntonviolins.com/blog
my work sites: http://darntonviolins.com and http://darntonhersh.com |
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Mat Roop Senior Member
Joined: 24 Mar 2007 Posts: 911 Location: Wyoming Ontario
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Posted: Tue Jul 18, 2017 10:51 am Post subject: |
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thanks Michael... your and Doug's points came thru loud and clear. I quite dislike doing soundpost patches... so was happy to hear that a skilful reglue often works.... difficulty is getting the glue fully into the crack without expanding the crack
On that point, I keep thinking if a vacuum system could work well to draw the glue fully into the crack... sort of like what is used for windshield repairs... has anyone tried it? .. probably would work best with the top off.
Thanks again!... Mat |
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Michael Darnton Moderator
Joined: 23 Mar 2007 Posts: 1286 Location: Chicago
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