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The first few guitars I've built I accidentally sanded through in the polish out stage of finishing, I'm sure many of us have had this unpleasant experience before. I've never been able to hide it to any success but did it anyway and of course it's visible. After that if it happened again then I would jut refinish the entire side that was affected and that worked but of course is more work.

Anyway I got in an old guitar that had a crack repaired in it but the person who fixed it tried to sand the crack flat and hence has some serious burn through. The sides are mahogany and the filler or perhaps that and a combination of age gave the original finish a nice deep red color but the burn through is fresh looking mahogany. I'm trying to blend it in with tinted laquer but having a real hard time getting it right.

Any tips or tricks you can offer?

Regards.

Yep! Most of the wood that is used gets darker with time, and many of the finishes also 'amber out'. As you know, that means when a fresh spot is sanded it will be lighter than the surrounding wood. I don't get in that trouble often (I reserve the right to commit other, more impressive blunders).

But I have mixed a little amber color in shellac or the finish you are going to use and rub it in with a gloved finger a time or two. It takes several coats and some addition of other colors at times to get it right. You want to stop when it is still a little light if you expect your finish to amber also. Then finish.

I think Dan at Stew mac did a tutorial on it also but I could be wrong.

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Joe Beaver
Maker of Sawdust

I hate stained or tinted finish... a lot of factory guitars stain or tint their finish and if I ever burn through them doing a repair it's impossible to match it so that is it invisible. I'm sure it's possible but in my experience it's either too light or too dark.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

You could start with potassium permanganate on the bare wood to oxidize it some, then use a grain filler/stain that matches what may have been used, then tone the finish to try to add back the opacity and ambering many old finishes develop. Touch up men charge a fair amount for fixing small blemishes in furniture. It's an art more than a science.

Fixing burn through eh.

Some of the brotheren have have posted on how to "Hide" burn through.

However the proper fix involves learning the loofer to be more attentive to his work in the first place.

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Audiences and dispensations on Thursdays ~ by appointment only.


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I agree. But that doesn't help the OP with his problem, which was caused by someone else's hand. Not his.
The way I have repaired this is to get me a piece of wood(mahogany, in this case, which is why as posted on another thread I NEVER throw scrap hardwood away) and experiment with different stains or combination of stains until I get something as close to a match as I can. Stain the bare wood(which is what the original filler did) and touch up the clearcoat.
Tinting for me doesn't work that well because while the tint might match on the bare wood, the overspray on the surrounding finish always makes it darker. Turns into a never ending struggle. For me, staining is the answer.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Padma is of course right. But if you do sand thru you want to do it on a newly finished masterpiece as opposed to an old one. Easier to fix that way. But then that is why experienced repair guys get the big bucks!

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Joe Beaver
Maker of Sawdust

Thanks guys...ya, me may be right but me lean more to the left....if
you gets the gist of the drift...what you expect, like me is a
Canadian don't you know... we even have free, walk in clinics
and medical system. ...yes it true!

You know ?adma woodn't be leading you down the garden path.

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Audiences and dispensations on Thursdays ~ by appointment only.


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Good ideas, I think I will practice on some bare wood first.