Canvas Deck & Rubber Paint

[SNagy]

I was advised by Nat Benjamin that when canvassing my plywood deck, I should set the canvas in a rubber paint. Rubber, because oil cause the canvas to rot. Has anyone experience with this issue? What paint do you use for this ?

Thanks.

-Steve

[Thomas Garber]

I used white lead paste as a bedding.

[Bob Cleek]

Yes, we got experience with that. There are a couple of ways to go. First, decide between canvas and paint or Dynel and epoxy. Canvas is traditional, but the difference in appearance from Dynel is negligible and Dynel/epoxy is far more durable and suitable for a plywood deck, which moves far less, if at all, than a planked deck.

If you are using canvas, be sure to put a layer of Irish felt underneath it. This will provide a moisture barrier and soften the hard spots which otherwise will wear through the canvas in no time. Then, paint the canvas. "Rubber paint" is really a misnomer. There are, however, a number of products on the market that have good flexibility, which is what you want. Oil based paint doesn't rot the canvas, exactly, but it hardens and then cracks, allowing moisture to get into the canvas, which does rot it. A more flexible coating will avoid much of that.

There is a product on the market that you can get at most any commercial paint store. It is an epoxy based paint made for painting garage floors. I know a lot of people are using it to paint the numbers on their sails these days, since it is flexible and won't crack and flake. I fear, however, that it only comes in black and white and, IIRC, cannot be tinted very well. Good stuff, though. Very durable for walking on.

All in all, if I had a plywood deck, I'd go with Dynel and epoxy. It will last forever and is relatively waterproof. Even the best paint on canvas will crack and requires constant monitoring and maintenance. We won't even think about that errant spinnaker pole or reaching strut end that will inevitably rip a hole in it!

[SNagy]

Thanks for the input. I've read some old discussions that essentially suggest canvas on laid decks, Dynel/epoxy for plywood. I would like to use canvas because my beam is 6' 9", and Dynel comes in 55" widths. I really don't want a seam.

[PeterSibley]

Bob, I've asked this before but didn't get an answer.
How would dynel(as against canvas ) go with paint...not epoxy...over boards? In favour seems to be that dynel is very strong and puncture resistant and won't rot.

[Dan McCosh]

I'm not sure what "rubber paint" is supposed to be--latex? There is a roofing compound--liquid neoprene--that is in fact liquid rubber, which sets up as a flexible coating. A sister ship had this applied to the canvas decks in the 1960s, over strip-planked cedar. This was not a new deck, however. The coating seemed to hold up well, but began peeling after about 30 years. Oddly, it had been painted regularly with sand and paint as a non-skid. When it began to peel, underneath the peeling sections was a layer of loose sand. The stuff was used just as fiberglass and resin were coming in, and the theory was that it would stay flexible. It does. Eventually, it was replaced with glass fiber set in epoxy.

[paul oman]

Both modern rubber/copolymer paints and very flexible epoxies are available on the internet. What about other non-skid deck options using colored chips, walnut shells, colored quartz sands, or ground rubber grit.

paul oman
progressive epoxy polymers

[Bob Cleek]

I can't say that I'd recommend paint over Dynel. It doesn't have the same texture and weave that canvas does. Paint will soak into canvas fibre, but Dynel, being a synthetic, doesn't absorb paint the same way.

There should be really no problem with seams if you use Dynel. There are a number of ways that seams can be handled with Dynel. If the surface will be fulled and smooth, you can feather in a seam with no problem. The process is the same as fibreglassing. You can also overlap seams, and then run a line of masking tape on either side and lay another run of epoxy thinned with sanding additive. Remove the tape and sand the "seam" smooth and you will get a nice smooth line where the seam is.

I've done canvas and paint over laid decks and I've done Dynel and epoxy over plywood. I'd be hesitant to advise Dynel and epoxy over laid decks because when they work it will likely crack. However, if you have ply decks, or a ply "subfloor" over laid decks, Dynel and epoxy is the ONLY way to go. You can't tell the difference from canvas really and it will last forever and stay watertight. Canvas decks are one of the traditional methods that new technology really has rendered rather obsolete unless you are doing a museum quality restoration of an historic vessel.