I continue to have varnishing problems. This time I de-dusted the shop and installed air filtration (JDS). The job is to re-varnish the boat I built last year, eliminating the thermal curing print through. I RO sanded the old varnish to 220 with the shop vac hooked to the sander, leaving most of the original finish on the boat. Then I vacuumed the hull, washed it down with plain water and a clean sponge, and let it dry. I did a final wipe with one of those new electro-static dust cloths, which left a clean dry dust-free surface. I thinned Captain's varnish with the recommended T-10 thinner, and brushed it on with a new foam brush. I dipped the brush in the can, and did not wipe it on the side of the can, just let it run off for a few seconds. The application was gentle, generally in one direction only. Now the problem - I got a slew of tiny bubbles. I waited a few minutes, during which time a lot, but not all, the bubbles broke. I tipped off with the brush lightly touching the surface at a high angle. This brought a zillion more bubbles, some of which broke. Now at the tack stage, I have the same bunch of bubbles I always get. The surface is rough, and would require rubbing out.

That was the first recoat. What should I do to on the next coat so I don't get the damned bubbles? I plan to sand the first coat with 220 dry, enough to scuff and hopefully take down the now hardened bubbles.

By the way, the de-dusting and JDS unit worked great. The two or three cat hairs in the varnish were probably on my shirt and got blown off with the exhaust from the filter. No other dust problems.

Any help, suggestions, or comments appreciated. - John