Searching for advice on waterproofing canvas

[Gunk]

Folks, I'm tweaking up my wooden Snipe for summer and made up several canvas items out of painters' dropcloth (sail/boom cover, cockpit tent, jib sock, etc.). I coated the material for a boomtent last year with a product from Olympic, but it leaked almost right away. Some people have used Thompson's water seal, but I've heard mixed results. I have some "303" I use on a bimini on another boat, but that stuff's too expensive for doing lots of sq. feet. So what is a good product for topsides canvas to repel water and also, if possible, protect from UV. Something you could roll on or spray with a garden sprayer perhaps. Is Thompson's viable? What do you think? Thanks for help on this.

[Andy]

You should be able to find plenty of specialist canvas sealing products if you do a web search - as for Thomsons, you could make up a test sample and then leave it out in the rain or have a go at it with a hose before you make any commitments to the rest of your material...

Andy

[PAR]

Thompson's is for wood and doesn't do a great job at that, you can guess how it'll perform on the duck covers you've made.

Boat covers need more than water proofing, they need protection from UV break down. Most RV stores carry a line of waterproofing/UV protection liquid, used on RV awnings and works reasonably well. Most come in a spray bottle and are easy to apply. This will be the low buck route that will work if the instructions are followed.

There is no good substitute for good cover material other then a garage.