water proofing canvas

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frosh coach

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My mooring cover is starting to allow the water to soak through. Does anyone have any suggestion on what kind of spray on "Stuff" works the best?
Thanks
 
303 High Tech Fabric Guard. Spray light coat. Let dry Spray another light coat. DO NOT soak it
 
Not for everyone...but I have an old top that I pulled out cuz the newer one was getting worn. That old one is near 20 YO and leaked with some recent rains. I got silicone and smeared it on the inside with an old 4"x10" piece of plexiglass as a trowel. Good enuff for the winter rains. I think that canvass will last another 10 years.
 
The most important first step to making boat canvas watertight is to get it clean first. The embedded dirt acts a conduit for the water to pass thru the canvas. If possible take the canvas of and either soak it in a plastic trash can with dawn dish washing liquid or better yet wash it the washing machine on delicate cycle. Do not put it in a clothes dryer or it will shrink. You can put back on the boat damp, let it dry then treat it with 303 Fabric Guard or other good quality waterproof product.
 
If you go to a camping store and get tent water proofing it will be much cheaper. My father in-law used to be a dry cleaner and when he retired he gave me a one gallon jug of waterproofing that he used to reseal raincoats with after cleaning, I don't know where to get it but it works great it is a DuPont product there is no label on the jug.
 
I had a really old sunbrella cockpit cover, laid it out in the driveway and rolled Thompsons Water Seal on it. That waterproofed it. It seemed a little heavier, but it was waterproof.
 
It's really not expensive. You just spray a light coat on it. One bottle lasts a long time. Avoid the urge to soak it.
 
quote:
Originally posted by MichaelNJ

303 High Tech Fabric Guard. Spray light coat. Let dry Spray another light coat. DO NOT soak it

Click to expand...
That's what Sunbrella (the canvas maker) recommends. AFter a good cleaning.
 
+2 on the 303. We had never done anything with our cover (we have a full mooring cover on at all times). Since "taking over" the boat from my parents after my dad died, we've been doing little things here and there. This season, we ran the cover through a big industrial washer, dried on the boat in the sun and then applied 3 coats of 303 (drying each in between) on the outside and then turned cover inside out and did a coat inside and that stuff WORKS!! Water beads right up on the cover now. Is also great for patio cushions etc. I'm not just using it on the boat cover.
 
i'm going to clean the cover and then use 303. When you guys washed your cover in the washing machine, did you use any cleaner?
 
Well personally, I goofed. I thought we could wash the cover by hanging it over the railed and using some spray 9 and water in a bucket with a light scrub brush. It didn't go as well as I had hoped so we then went to the laundry mat and did a cycle with a BIT of detergent and let it go the whole cycle, then I ran two more full cycles with no detergent at all to make sure it was super cleaned of any of the soap. I would just go right to the laundry mat next time, a bit of soap and a full cycle, then at least one cycle with no soap.
 
There are care and cleaning instructions on the Sunbrella web site. I have white covers that I had made for the seats on my flybridge. I wash them at home with detergent and bleach.
 
If its Sunbrella, you should follow our care and cleaning instructions for the best results and a long fabric life (on our web site). CRay is correct about cleaning. That is an absolute must before applying any treatment to any fabric. MichaelNJ and Watson524 are correct about 303 coatings (two light coats is preferable to one heavy coat). With regards to Babalong's use of Thompson's water seal, there are many people that swear by it. However, our R&D folks report that in tests it makes the fabric brittle. It's application would also void your fabric warranty. We hope this helps.
 
We have used 303 in the past. We switched over to Starbrite brand, which we can purchase by the gallon. The gallon of Starbrite is $44. We haven't found gallon size for the 303, and it is about $30 for their "large" 32-oz. bottle, which is $120 per gallon if you get 4 of them.

We pour the gallon of Starbrite into a 2-gallon garden sprayer that has a small hose/wand. We set the canvas on the ground, and spray the whole thing down in about 3 or 4 minutes on the fine spray setting. We find that the heavier coating we put down with the sprayer lasts lot longer than the 2 light coatings we used to do with relatively small 303 bottles. Sure it takes longer to dry when we soak it with the big sprayer, but still only about an hour out in the sun..... and it lasts a lot longer.

What we don't know for sure is what makes it last longer. Is it that we are doing a heavier coating, or is Starbrite actually better than 303? We don't know. What we do know is that a heavy coat of Starbrite easily outlasts a couple light coats of 303.
 
I took my canvas to the laundermat and used the jumbo washer. I used woolite. I then used starbrite waterproofing and sprayed it on using a garden sprayer. The water beads up great.
 
Sounds like another vote for Starbrite in the garden sprayer.
 
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