MIMF

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 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.

Sorry about that bad pic.
This should be better

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

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.

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

Good idea Bryan.

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.

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.

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.

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.

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.