Just finished an orange opaque lam (RR KK epoxy, if it matters) and noticed color is slightly lighter in the area where I did a lap-cheater coat on the deck. No problem at all on the bottom where no cheater coat was done. What’s the best way to avoid this slight discoloration in the future?
Color the cheater coat the same orange (I did it clear).
Don’t do a cheater coat at all (despite increased danger of foam damage when lap sanding).
Add more pigment to make the resin even more opaque (you can still see the stringer so it isn’t 100% opaque.
Jamie I’m sure someone will have a better answer but the best results I had for this situation in PE, still a big PIA but turned out pretty good -
mix up one huge uncatalyzed opaque color batch, split for deck set aside, lam bottom with cut lap. lightly seam roller press the edge into the foam, don’t create a dent & no basting.
2 stage deck lam. first layer with the color batch, zip lap - saturate rails let it hang but don’t wrap it - just as it’s gets sticky tuck it below the rail apex, as you near the tail tuck to the bottom edge. when it’s semi hard razor cut the hang. Clean up the edge but don’t mash it, carefully get rid of any high/low spots or excess glass that will “collect” resin and show as darker spots.
Lam 2nd layer clear, lapped
Pic below taken right before I took razor to the hang
Bud’s method looks great but he says its a lot of work. Another option is a foam stain… I use a (disposable) foam roller on the blank with pigmented resin, let set, flip & do other side with a new roller… then clear lam as usual. Super easy and looks good. Also easy to do half the board (just tape off) if you want a two-tone, etc. here’s a two-tone foam stain (red part):
PS this board has gone missing, if anyone sees it let me know!
I did do a two-stage top lam. First layer color cut at the apex. Second layer clear full rail wrap (with logos and vector net in between). Cleaned up the apex seam with a air-grinder and everything came out fine on the rail and the bottom. Problem is definitely with the clear lap baste on the deck, since the color layer can’t absorb into the foam in that area it creates a discoloration. Since it’s epoxy I can’t mix one big batch of resin, but I did one batch of pigment, which I used for both top and bottom to color match. One thing I know is I can’t do a clear baste on the deck seam. Just need to figure out if one of my options above will work. Greg Loehr did an opaque in his glassing video and he doesn’t baste the lap, but he did make it a point to put a lot of pigment in the mix so the resin was totally opaque.
Keith, Foam stain sounds fun, maybe I’ll give that a shot next time.
Board turned out well besides that. Just always shooting to improve…
I’ve been doing a bunch of opaque tints lately and I’ve run into your same issue. Now I add pigment in every step of the lam. I mix color into my micro-ballon slurry mix to seal the blank, then I lam with pigmented resin. I do my fill coat with pigmented resin too. I rough sand it all with 80 grit to give an even surface and a chance to fix light spots, then add logos and do a final clear hotcoat, sand, and secret sauce. This definitely adds more spetsto the process, but my best results happen when I go this route. Also use lots of pigment. A good way to check if you’re using enough is to check your mixing stick to see if the wood grain is visible through the resin.
Why did you feel you need a cheater coat?? And-- Why did you do only a partial cheater coat?? The fact that you did a partial is the problem. There are things that shouldn’t be attempted with Epoxy. Not saying they can’t be done, just have too compensate. Basting and cheater coats are no prob with Poly.
I basted the deck lap with clear epoxy so I could grind the lap edge smooth without worrying about gouging the foam. Obviously this clear baste was the culprit. Question is what is the best way to avoid the discoloration in the future? I’m scared not to baste the lap as I like a good aggressive lap-grind to avoid other problems down the line (bubbles, burn throughs, etc.). There are probably many solutions, including coloring the baste the same color, or going with more pigment to make the color truly opaque.
