Fixing Blothcy surface in Rosewood

[Michael Baresi]

Hi All
I am currently restoring an 1895 August Pollmann parlor guitar. Someone had previously refinished very poorly with what appears to be varnish. I have removed all of that finish and sanded with 120 and I have found some blotches in the finish that cannot be sanded out.
I am thinking about applying a glaze to try and even out the blotches but wanted to get other opinions first. Any ideas?
thanks

Color has changed as I compressed the file.

After seeing the post I realize the color is dramatically different because of the file compression. The blotchy area I am referring to is the darkest parts in the upper bout left of the center line.

[Michael Baresi]

Sorry about that bad pic.
This should be better

[Barry Daniels]

That sort of looks like oil has soaked into the wood. A dark stain may help. Probably couldn't hurt.

[Bryan Bear]

If you haven't put anything on yet and Barry is correct that it is oil soaked into the wood, you might try naptha. I once left a back sitting on an oily surface for weeks and it soaked up a good bit of oil. I liberally applied naptha and let it soak in then evaporate. It took a few applications but eventually it took all the oil with it. I had no finish issues on that back either.

[Michael Baresi]

I don't think that it is oil but rather finish that was applied without a sealer but naptha is certainly worth a try. I'll give it a shot.
thanks

[Barry Daniels]

Good idea Bryan.

[Michael Lewis]

It may be interesting to see what it looks like when you wet it with naphtha. You also might try a liquid or gel stripper to remove all remnants of the old finish.

[Michael Baresi]

Thanks Michael but I don't believe there is any finish left unless it is soaked all the way thru. I sanded until the back was getting noticeably thinner and I dared not sand any further. Naptha didn't work for me but thanks for that suggestion Bryan.
I applied a glaze and softened the edges of the blotches trying to blend them into the back. This is the result.

[Michael Lewis]

The reason to use a stripper is to avoid removing any wood while removing the old finish. Just keep this in mind if you ever do something like this again.

[Todd Stock]

Ditto stripper - naphtha will not touch cured oils, vanishes, or other penetrating finishes...useful for grease and oil removal where the stuff is not a curing oil, though.

My guess is that the staining is a penetrating sealer, which could be any number of things (polyester, polyurethane, lacquer-based sanding sealer, penetrating wiping varnish, etc. - s good traditional solvent-based stripper will handle them all. Wear gloves, eye protection, and if chemically sensitive to stuff like methylene chloride (aka, dichloromethane), which most of us are or may become, wear a respirator. This stuff will dissolve most glues and plastics as well, so be careful around joints and stuff like bindings and purfs.

[Clay Schaeffer]

I usually try to strip finishes with lacquer thinner before going to methylene chloride strippers. To me it seems the clean up is a little easier and the surface needs less prep work for the new finish. It doesn't work for all finishes so methylene chloride is sometimes needed. Like Michael, I try to avoid anything more than a very light sanding.