On Dec 17, 10:24*am, wrote:
I was just given the go-head to refinish my wife's parent's old dining room set. *It was purchased in 1940 (my wife still has the receipt!) and it is in dire need of refinishing. *There are 70 years worth of fingerprints all over the backs of the chairs and there are several nice gouges in the top of the buffet. *The finish on the top of the backs of chairs is really coming off, too, and you can see different colored wood starting to show up on all four of the chairs. *Of course, there are a lot of scratches on the table top from cats and kids and whatever over the years. *And you can see all the cracks and discoloration of the old varnish--at least I think it is varnish.

That is the first question: how do I figure out what they used to finish the dining set? *Varnish, shellac, what else would they have used seventy years ago?

Factory made from that time might be lacquer;
cracking would be expected. Butyl cellosolve
-- *slow* drying solvent -- can be used to reflow
and reamalgamate the old finish.