We switched to Bristol about ten years ago and will never use varnish (or anything else) again.* Bristol takes some getting used to in terms of its application, but once the technique is mastered we have found it to be so superior to varnish that in our opinion, varnish is not even worth considering anymore.* At least not in our climate (PNW).* I have no idea how it does in hotter climates.
We far prefer the thin consistency of Bristol to the heavier consistency of varnish.* When applied correctly-- and that is the key--- we get fewer runs, sags, or uneven surfaces than with varnish.* In our experience, Bristol lasts more times longer than varnish for us to count.* Our boat sits outside year-round and we have pieces of exterior wood that received some ten coats of Bristol seven or eight years ago and have not required a new coating although after this time the finish on these pieces has dulled somewhat and a new coat would be a good idea.
The only issue with Bristol is that it can soften and distort vinyl and other plastics before it's dried and cured, so it should not be used over lettering on nameboards and such unless the lettering has been protected with a coat or two of varnish.
We have met a number of people who, like other posters here, had a tough time figuring out the application technique of Bristol, particularly on vertical surfaces.* So they decided they didn't like it and went back to varnish or some other product.* But everyone we know who has used the correct application technique ends up feeling the same way about Bristol as we do.
On bare wood we apply Bristol over an initial coating of CPES that is still a bit tacky, which we have found improves the adherence and longevity even more.* This technique is equally effective with varnish.
Bristol is not a magic bullet, and like varnish, the more coats applied the better the longevity.* We shoot for a minimum of six coats but prefer to get ten or so on.* Also, as with varnish, the longevity of a Bristol finish is dependent on the integrity of the bedding of the wood to the cabin side or whatever surface it's attached to, and the integrity of the joints in the wood.* If moisture can get under the surface via poor or failing bedding or open joints, it will lift the Bristol finish same as it would a varnish finish.* We have found the CPES is a help in this regard.
-- Edited by Marin on Tuesday 5th of January 2010 01:01:07 PM
