Allen Brown

I am finishing a canoe paddle with West System 105 & 206. I have one coat on already. My question is, after I get the first coat to cure, can I add a sticker to the paddle, and then coat over the sticker?

Thanks,

Allen

Allen Brown

Also, what should I sand the first coat with, before I apply the second coat? I need to sand a few spots, because I got some outgassing bubbles on the first coat.

wrc.six.eight

You might be opening a can of worms with the sticker.
The possibilities are that it will disintegrate or smear and not allow the epoxy to cure. The epoxy might cure over it but adhere poorly and flake off in use. If the epoxy does cure over it and does not smear it the bond will only be as good as the adhesive on the sticker.

On surfboards, logos or such are printed on rice paper and laminated under the fiberglass.

West epoxy forms an amine blush on top of the cured layer. This must be removed just prior to recoating. Since epoxies have much greater bond strength than Polyester resins they do not need as much 'mechanical tooth'. The rule of thumb with polyester resins was minimum of 120 grit between layers. With epoxy you can get away with some water and a scotch brite pad to get rid of the blush.
With System 3 SB112 epoxy I have wetsanded to 2000 grit and then smeared on a layer to achieve the wetlook. No bonding issues.

About the outgassing bubble. It is likely to form again, same spot on the successive layers. Apply the epoxy when temperatures start falling, or get some thick, clear 5 minute epoxy and fill the void with that, then cover with the 105.

If your project is going to see a lot of sunlight cover the epoxy with some quality marine varnish.

Allen Brown

Thanks for the info.

So, if I dont UV protect, what will the sunlight do to it?

wrc.six.eight

Over time lots of UV light will first make the epoxy cloudy, then white and brittle.

Some epoxies have a lot of gloss when they dry, but if then you sand to 2000 grit and try and polish them, they will not have that wet look. I once followed the above procedure on an 9'6" inch western Red cedar surfboard. Then I used some meguires car polish on it and he thing was outstanding looking, for about a week. Something in the polish was reacting with the not fully cured epoxy. I basically has to sand it back down to the fiberglass and re 'hotcoat' it.

Thats when I figured I could wetsand it to 2000 grit and then smear a super thin layer over the whole board. It works well, but not as rich and mirror like the meguires.

After a month I felt safe enough using a regular paste wax on the board.

I would use varnish but it complicates any future necessary repairs.

I used system 3 sb112 epoxy which claims to contain some UV filters and have not yet noticed any UV damage on my most used/ uv exposed surfboard. I think it will take about 4 to six months left outside for any damage to appear, but once it starts the integrity is gone.

wrc.six.eight

some epoxy
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