someone gave me alot of bottles of old tung oil products, are they still good?

these are old formbys high sheen tung oil mix, that's a new bottle I had on the left, I put a few bottles with my paints, not sure what to do with all of them.
They were still sealed, broke seal on one, and rubbed it onto a piece of walnut scrap, it seems fine.

does this stuff break down? Im waiting on the morning to see how it looks.

The date on the new bottle I just purchased recently says 2002, the old bottles say 1980.

I think the only real way to find out is to try a bit on a test board, but I'd be willing to bet they're toast. I've had previously-opened cans of Formby's Tung Oil Finish turn to gel in less than a year.

I think what your 'friend' gave you was a toxic waste disposal problem.

Formby's Tung Oil finish is nothing but wiping varnish according to Bob Flexner. I looked at the MSDS, and it's really thin varnish; 78% MS by weight. Unopened cans of varnish keep literally indefinitely, so my guess is the sealed containers are still good (your test will prove that, if it cures, it's good). Any that are opened may have started the curing process, and if so that fluid will be much thicker than it would be, possibly to the point of being unusable. Once varnish starts to cure, it's not a reversible process so any like that can be disposed of.

Fred may have the best reply. Pure tung oil is practically archival. What you have is sumptin' else.

If its not jell its probably mostly ok unless there is some chemical reaction that I'm unaware of taking place (always possible )

I'd suggest trying a thin dribble on a none absorbing surface (not wood - like glass, formica, tile, etc..) and make sure it cures hard there. If it cures good, its fine.

seems fine, its identical in viscosity to the new one I have.
Im going to finish off the inside of the piece with the old stuff, just in case, let it sit a week while Im gone, then see how it looks.

Carol Reed said:

I think what your 'friend' gave you was a toxic waste disposal problem.

Click to expand...

he also gave me 4 bottles of formbys lemon oil, also 30 years old, but unopened, and it looks perfect also, I gave them away this morning to someone who I thought might use them, if not, they can dispose of them easy enough.