: After painting a canvas kayak, I want to varnish it. What will I have to do
: to prepare it for repainting? Can I paint over the varnish?

I did a series of tests 2 years ago with varnish on canvas. I also did oil paint on canvas and varnish over that.

First: Varnish on canvas make for a very brittle situation.

Second: The varnish over paint made for some strange colors. Many Spar varnishes carry with them a yellow tint. This turns a blue kayak into a green yak. UGLY GREEN.

Third: The varnish was no help to the strength of the canvis and where it soaked in it became brittle.

Forth: One of the advantages of paint is that you can repaint. With varnish on the boat, don't plan on doing paint touch-ups.

My conclusion... Varnish and canvis don't mix

Roger