Steve,

I used Schooner varnish unthinned and am very happy with how it turned out. That was when the temperatures were high 60's, low 70's at night, mid-80's in the day. I put the varnish on first thing in the morning and it was hard enough for wet sanding when I came home from work. If I'd tried working in the middle of the day, I'd have needed the thinner.

 Nice boat, BTW,

 Laszlo

Very nice job Steve! You'll definitely need to thin the Interlux Brightsides to get a streak-free finish if you're using the roller/foam brush method.  Use their thinner and follow their recommendations.  I applied three coats of white under one coat of Interlux Pre-Kote last July in my basement with evening temps. in the mid 70's.  I tried to apply the 2nd coat unthinned but was unhappy with the results.  I sanded and applied the last coat thinned and all was good.  I used Captain's Z Spar varnish on the deck and only thinned the intitial coat of 5. 

Laszlo: So is the overall purpose of thinning varnish to make it dry slower or to make it more brushable (or both)?

Chris: Great looking finish! What ratio of paint to thinner did you use?

-Steve 

The directions say not to thin more than 10% by volume.  I poured some paint in a clean container and added thinner slowly until I liked the feel of it when stirred.  Nothing too exact.

Chris 

Steve,

Yes. It can help extend the useful temperature range some. I've just waited for the weather to cooperate, but some of the other builders who post here add all sorts of stuff to the varnish and get good results.

Laszlo

Chris,

I just put on 3 coats of Brightsides White on my CH16, but it has not evened out at all. I can still see the tippng strokes. I followed CLC's intructions to the letter but am disappointed with the result. My painting conditions were pretty much ideal, I think. I have a feeling that I should have thinned the paint but have not experience doing this. I'm looking for that sprayed on, auto finish. I hope this is still possible since no one will see the hard work underneath, just the finish on top. Any advice on this problem would be appreciated.

Would Penetrol (flowing agent) help?

whatever you use ,transfer to a glass jar with a screw on lid and use a varnish strainer [ they look like cofee filters ,you can get them at a paint store]other wise you can get little chunks of dried  varnish

I love it when I buy a new car and it gets some dings so that I can stop worrying about getting some dings.