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Sailor
11-17-2010, 08:12 PM
Ok, I will admit that my canoe is NOT a compromise. I know that every boat is a compromise... but Mine's NOT!!!
Now that that's out of the way, It's not perfect either. I didn't do the best job at glassing the hull and needed to apply another layer of epoxy to the hull when I realized that there was not enough material to remove to fair the hull correctly. So I roughed up the surface with some 60 grit and applied another coat. Today I noticed that even after washing the hull there was a greasy feel to the hull. I sanded through it and it was properly cured underneath but I can't figure out what that film would be. The film gummed up the sandpaper pretty quickly and even seemed "sandpaper proof" for a bit. I also noticed a blood red liquid forming into droplets around the perimeter of the boat. I don't recall either of these phenomena happening when I originally glassed the hull. Anythoughts on what may be causing this? How do I fix it? What do I do next time to avoid it?
Oh yeah, the weather wasn't perfect for epoxy. It says on the can (west system) that it's good down to 4 deg C. It was around 13-15 degrees out. It was a bit humid out but I was indoors under cover of a roof and walls. Could this have affected my cure? It cured for about a week and a half, with days up around15 and some nights that were below freezing thrown in just to ensure that I love my Nova Scotia weather patterns?

G. Schollmeier
11-17-2010, 08:30 PM
This may help you.
http://www.epoxyproducts.com/blush4u.html

Bill Huson
11-17-2010, 08:47 PM
Yep - blush. Wash the hull with plain ol' water and proceed with sanding. With WEST you should be using 207 "special clear" hardener. Slightly more UV resistance, clear as advertised to show off pretty wood, and less problems with blush.

Sailor
11-17-2010, 08:54 PM
Yup, blush for sure. What about that red liquid?

Cuyahoga Chuck
11-17-2010, 09:08 PM
I can't say for sure what your red liquid is but I know from experience that West harder will turn red when it gets old. The hardener still works but the it stains the epoxy red if you use it.

Tom Lathrop
11-17-2010, 09:16 PM
The first thing anyone learns about epoxy is that it can blush sometimes with an amine waxy substance migrating to the surface. As said, water gets rid of it while sanding does not do it very well. The red stuff may be your blood from all the sanding. Oh yes, you did compromise the weight of your canoe with all that added fairing needed to make it smooth and fair.

Gerarddm
11-17-2010, 09:47 PM
Did you contact West System customer service and ask 'em?

Eddiebou
11-20-2010, 08:22 AM
One of the best things I ever did was pick up a simple flat cabinet scraper. It works wonders on epoxy, especially when it's "cured" but still too green to be sanded. It will pay for itself many times over in saving labor/time and wasted sandpaper. You can scrape between coats w/o washing away the blush.