Wipe on MinWax...

[Bill Holt]

...is my go-to for finishing turnings; mostly bowls.  I use paper towels to apply the finish.  As you might guess, even with three coats, a can last a long time.

Problem: the once thin liquid begins to thicken.  I have added paint thinner several times, with little change seen.

Question: once it begins to "jell", should I just give up and buy a new can?

[fredhargis]

The finish in the can is actually curing. Thinner can help early on, but not after the curing has advanced to a certain point. Eliminating air (actually, oxygen) from the can would stop or significantly slow the curing process. That's not easy to do, there are store bought gases made for this that can be squirted into the can (Bloxygen is one),and some folks have tried gases that aren't made for this...like propane from a torch. I even tried homemade CO2 (mix vinegar and baking powder) and truthfully it was as good as anything else....that is, not very good at all. Some folks turn the can upside down after the lid is back on it, I don't see how that helps but they say it works. A better method may be to put marbles (or clean gravel, or whatever) into the partially filled can to raise the finish level to the top, then seal it. Another solution would be to use Stop Loss bags, I currently use these and so far they have worked very well....but they are a small pain to use. But to your question, yes once the curing has started the finish is going bad. Early on it can be salvaged, but it will be unusable after a short while. But while it's fluid, it should still work. So if you just get a skin on top, take it off and use what's underneath.....quickly.

[jteneyck]

Transfer it to smaller bottles when you buy it. Keep them in the fridge and they will last for years. Only remove them as you need a new bottle. Putting a partially used bottle back in the fridge between uses is quite effective, too.

John

[Willyou]

The Stop Loss bags that Fred mentioned works very well. Ordinary ziplock bags will also work, but are a little more difficult to work with. As they are not as thick, I would double them.