Anybody know anything about finshes Shellac Nitro Laquer and French Polish Shellac?

Sambostar

A '30's/'40's era cabinet and I just wondered if anyone could throw some experience on why some of it is reactively blistering when I add alcohol.  It's almost acting like paint stripper on paint in places, where as most spots it is just going soft and sticky as per would be usual for shellac  I'm refinishing it anyway, but just curious to what the finish was.  Guess it was some hybrid mix of something sprayed on for cost.

Is the finish some sort of cheap mix of nitro and shellac?

WezV

shellac does make a good sanding sealer, so its quite possible they sprayed nitro over shellac

Sambostar

What happens when you soak meths on an R9?  Does it blister?  I know Nitro is semi soluble in alcohol but Acetone is the real solvent deal?

It may well be shellac, just that I am shit and completely unskilled.