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This is on an unfinished guitar that I am doing the final sanding on. I've got a small ding near the edge of the soundboard that must have happened when I had shellac there for cutting binding channels. I can't steam it out because there is shellac down in the dent, so it won't absorb moisture. I'm afraid that trying to scrape the shellac out will make it look worse. How do you deal with this? It's pretty small. Should I just wait and fill with CA after I've started French polish?
Wendy

Disolve the shellac with acetone, then steam the dent out. Acetone is flammable so let it dry before you start steaming.

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You can steam right through the shellac. Shellac is not a very good water barrier(arbitrary to many opinions!). Put a drop of distilled water in the ding, wet a piece of paper towel, and put it on the spot, then put the hot iron to it. You'll have to touch up the finish, but it'll steam out just fine, assuming the wood is not cut. I have done it many times.

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Waddy

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Why not just alcohol? I'd think that would dissolve it and it could be sponged out.

Kind of on topic but maybe more of a "tip", but the absolute best tool I've found for dings is a Weller "Expert" 100/140w solder gun (been around a long time....looks like a pistol) with a flattened "spoon" tip. It's brilliant! Fix them as they happen by putting piece of wet T-shirt overtop & touching the hot spoon. Very localized & controlable.

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Dave
Milton, ON

http://www.youtube.com/watch?v=pDSQ7u_ii00
this will get it out . Simple and you can use a steam iron if you don't have a soldering iron

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Thanks for the replies. Waddy, there is no finish on the guitar yet, shellac just down in the very small ding. I already tried to steam it out with the shellac still in there and it didn't work. Woody, why acetone instead of alcohol? I haven't tried dissolving it yet. I have a very small iron used in picture framing, called a tacking iron, and it works great for steaming out dents. I'll watch the youtube video later today after work. Thanks, Wendy

If that's the case, it may be broken wood fibers. In that case, it won't steam out at all.

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Waddy

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If it is broken wood fibers, then what would be the best way to fill it. It is on the edge of the spruce soundboard right next to the binding. Should I wait until there are a few sessions of french polish on and then fill with CA. Can I just try and fill it level with shellac a little at a time? I think any kind of fill with sawdust is going to stick out like a sore thumb.

Filling on Spruce is troublesome. Maybe finishing then using CA would be a decent bet. Maybe some others have a better suggestion.

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Waddy

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Shellac is actually a pretty good water barrier. Check out this report here:

http://www.fpl.fs.fed.us/documnts/fplrp/fplrp462.pdf

Shellac is finish #s 22 and 23 and you can see that it actually performs pretty well, especially when compared to other finishes like we're using. I used to have another study where it did even better (I don't think they were comparing exterior and other pigmented finishes) but I can't find it right now - it's lost in the bowels of the "library" which hasn't been updated in 10 years on another forum.

It would probably be worth trying to dissolve the shellac in alcohol or acetone and trying again.

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I don't know what the tests were, but I have steamed more than a few dents out of a guitar top with a fully French polished finish. I did nothing to dissolve the shellac. Used water and paper towel and an iron. When done, the shellac is practically gone from the area. I steamed some 50 to 60 pick indentations out of my #3 guitar where a student of the guy who has it, picked it up and waled away with his pick. What a mess. They all came out without much effort. I admit they weren't very deep, but I did nothing to remove or dissolve the finish. I wet the area till water was standing in the grooves, wet a paper towel, covered the area, and put a really hot iron on it and watched the steam for a few seconds, repeated. Nearly all of the scratches puffed up. After it dried, I had to sand it a bit to level the raised areas. Touching up the FP was harder than steaming out the scratches.

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Waddy

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