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Hi all

I am working on a guitar that need a section of the top replaced. A nice sized piece about 3x8. The current finish is polyurethane. What would be best finish for the repair? Is nitrocellulose an option or should I use polyurethane. I will need to feather it into the existing finish. Any thoughts about EM 6000 from target coatings?

thanks

Hi Kevdart and welcome to OLF. I'm not going to try to answer your question as I have had very little luck with this, but I'm going to watch what others have done. I've reached the point where I usually turn down repairs involving any of the modern poly finishes because I know I won't be satisfied with the results.

Are you sure you need to patch the soundboard? There may be alternatives. How about a picture.

Time to manage expectation and not promise the impossible. Or the uneconomic.

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Peter Havriluk

Thanks for the replies everyone

I guess I should not have said a patch. The piece is missing so it must be replaced -Although it sounded ok with it missing strangely enough. I do agree that the repair is probably not worth it but its for me and more or less a learning experience. I do not expect anything approaching perfection but we will see how it goes.

Wow. A whole new top would be more appropriate.

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"Act your age, not your shoe size" - Prince

Actually the repair might not be all that hard. I would approach it in these steps. Glue the present top back to the kerfing , make sure the braces are tight while you can get inside. Glue a piece of reinforcement to the present top leaving half of it extending into the void. It looks like the binding is still in place, cut a piece of wood to fit against the top and inside the binding. It should just drop in place. You will need several long clamps to reach the reinforcement thru the sound hole and several spool or quick clamps for the rim.

The top looks like cedar to me but it could be spruce. Rather than trying to match the finish and deal with something that I don't know, I would probably strip the top and refinish it - either FP or nitro would work. You might be able to do it with some of the new wipe on polys - I have no experience with them so I can't say. When you cut out the piece to fill the hole keep the scraps and use them to practice your finishing technique.

Good luck