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View Full Version : Best repair techniques for damaged grand piano case?



Alan Caro
03-02-2020, 9:29 AM
Creekateers,

I recently had my Kawai KG5-C 6'8" studio grand piano >

427199

> moved cross country. The thing is I hadn't seen this piano before the previous move into storage in 2012. When I looked it over after it was moved into the house a couple of weeks ago, I saw this:

427200

That's on the tail end near the rear leg, on the straight side.


Problem: The mover showed me an inspection chart made before moving showing this damage this damage was present before he moved it, meaning it happened on the previous move into storage. While I contest this as I believe I saw it happen- the sound and there were wood chip on the sidewalk, the probability is that I'll have to repair myself. As usual, the insurance company will spend more on fighting the claim than the claim amount.

There is of course, the wood to restore; I'm thinking to scribe an outline with a little depth on the bottom to prevent chipping out when cleaning out a more or less cubic space, trace the scribed opening in plan, let in a shaped Oak piece based on the tracing, then reapply the finish and blend into the original. Fortunately, it's not in a conspicuous place and a limited area. I'm not sure my very limited chisel selection includes the right tool- would a mortising chisel be the best choice?

Suggestions gratefully received.

Alan

Kevin Jenness
03-02-2020, 12:37 PM
Normal technique would be to cut the male inlay piece and scribe around it to lay out the pocket. Chisel type is not important.

I would be tempted to use epoxy putty after removing any loose fibers as it is basically a cosmetic repair.

Is that part solid wood or edgebanded plywood?

Alan Caro
03-02-2020, 6:12 PM
Kevin Janness,

Yes, of course, it seems more sensible to make the inlay piece first and scribe around it rather make the pocket first..

The wood is solid with a very thick lacquer finish.

I've never used epoxy putty. Do you mean for the putty to fill between the inlay and case component or is the putty the adhesive? Does that putty come in colors?

Thanks!

Alan

Kevin Jenness
03-02-2020, 6:42 PM
I was suggesting using epoxy as the fill as opposed to making a wood inlay. Polyester putty (bondo) would be similar, though less strong and shrinks more. Once finished the appearance would be the same.

The greater challenge will be repairing the finish. If you want an undetectable repair you may want to bite the bullet and get a competent refinisher to do the job. In either case, I would suggest blocking up the piano and removing the damaged piece to work on it.

Jim Becker
03-02-2020, 7:44 PM
I'm with Kevin here given that appears to be a cosmetic issue rather than something structural that brings risk to the viability of the instrument. And yea, the filling part with resin and scraping/sanding it down to the contour is the easy part. Your big challenge is going to be repairing the glossy finish. I also agree with removing the piece if that's possible because you would then have the option of getting the assistance of someone with expertise in this kind of glossy finish. The kinds of products used are not "compatible" with in-home application as well as the "finishing the finish" work.