HELP! Varathane getting spotty finish

[Malcolm Schweizer]

This is a brand new can of Varathane. I filtered it into a fresh clean can before use. It is getting clumpy bits in it. It matters not if it is thinned or straight. It looks like dried bits of varnish, but it is a clean brush, new varnish, strained, and clean surface. I even took it home to try it in my living room because I thought it was dust. It isn’t dust. It’s like the varnish is curing in clumps. It’s not too thick of a finish. I have tried thinner and thicker applications. I’m going insane here. Help.

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[Prashun Patel]

What did you thin it with?

If it's drying in clumps my first thought is an incompatibility in the solvent or surface contamination like silicone.

And while you mention clumps, I see a lot of air bubbles. That would speak to a thicker coat that is drying too fast on top.

What's your ambient temp?

[Malcolm Schweizer]

What did you thin it with?

If it's drying in clumps my first thought is an incompatibility in the solvent or surface contamination like silicone.

And while you mention clumps, I see a lot of air bubbles. That would speak to a thicker coat that is drying too fast on top.

What's your ambient temp?

thinned with Mineral Spirits. Ambient temp is 70-ish. Those aren’t bubbles. I couldn’t get a close up. It’s like little flakes of varnish that appear as it dries- after a few minutes- and they cause surface tension around them.

I wipe down before application with mineral spirits. Tried using just a cloth, and using just a tack cloth as well- same result for all three options.

I went and got some Watco wipe on poly. Didn’t have this issue, but it looks streaky and I need a smooth finish. This is a $$$ table for a customer!!! It is an antique that I’m refinishing, and they specifically wanted a polyurethane finish for durability. Tried to talk them into a French polish, as this is what the table had. This is the last coats and I did have some fisheyes in the first coat, but put a layer of shellac on and the next coats went ok, but the last few this is happening. I think this is a bad batch of urethane, but I got another can and same thing/ BUT it was from the same store, so same batch likely. Ack. I have made hundreds of tables and never had this problem, but I don’t usually use satin. I usually use gloss. I did stir this very well and filtered it through a paint strainer.

[Jeff Roltgen]

Sand it , buy a can of minwax satin poly and continue. Might very well be the simplest pathway through this issue, as blunt and unscientific this response is. You have a project to deliver, Varathane failed, = must move on.