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Re: Varnish bubbles
By:Paul G. Jacobson
Date: 8/18/1999, 2:40 pm
In Response To: Varnish bubbles (Dave Abbott)

> I just brushed on the first coat of Captain's ZSpar varnish and am
> concerned that tons of very small bubbles appear on the surface. When I
> ran my disposable foam brush over the bubbles, they just became smaller.

> Is this normal in the first coat? Will sanding with 400 grit prior to the
> second coat solve the problem?

> This is my first varnish job and I do not want to mess it up, any
> suggestions would be helpful.

> Dave Abbott

Sounds like you shook or stirred the varnish before using it. Let the can sit a day and don't agitate it before using it. See if you still get bubbles. A bristle brush may work better if you find that your foam brush. If you push too hard with a foam brush you could be pumping air bubbles into the finish.

It is not normal, and a light sanding with even a coarser paper (120 to 200 grit) will be fine for the second coat. Because of the solvents in the varnish the first layer of the finish will slightly melt into the second and smooth out a bit more. Save the real fine sandpaper for the next to last coat.

Paul G. Jacobson

Messages In This Thread

Varnish bubbles
Dave Abbott -- 8/18/1999, 2:09 pm
hate the bubbles, heat the varnish
Pete Ford -- 8/19/1999, 4:26 pm
Re: Varnish bubbles
Paul G. Jacobson -- 8/18/1999, 2:40 pm