The past two boards have had pimples shown below across the entire board surface. I use RR Kwik Kick, following the temp ranges per spec… Something changed and I think it’s my method. Maybe Im pushing too hard when I laminate, removing too much resin? But its one large flat surface, so why wouldnt the defect be uniform? Unless the resin reduces in volume slightly when it dries, that might pull in towards itself and if there’s not enough, leave spots dry on the surface?
UPDATE 12/24/20: I left the PTAC/fan off for my build this week and the problem didn’t occur. So if you want a nice smooth bone white surface, dont blow dust all over the damn room while the glass is wet.
What are you wiping the lamination down with before the filler coat? Are you sanding the lamination before you do your filler coat? Those two questions may seem odd, but will help me better understand what is going on.
Hey man, thanks for piping in. This pic was taken after the fill coat and sanding. The pimples aren’t very visible of course before sanding, because the indented portion stays glossy while the sanding level becomes matt. So the contrast in light reflecttion reveals it. My laminations have become tighter. First 5 boards I left a fair amount of resin in the weave to fill it up. Now I push the squeegee harder so when it’s dry, you can see a bit of weave peaking out. Then I fill coat to level all that out. Not sure it this is causing it. Maybe air bubbles?
Hey man, thanks for piping in. This pic was taken after the fill coat and sanding. The pimples aren’t very visible of course before sanding, because the indented portion stays glossy while the sanding level becomes matt. So the contrast in light reflecttion reveals it. My laminations have become tighter. First 5 boards I left a fair amount of resin in the weave to fill it up. Now I push the squeegee harder so when it’s dry, you can see a bit of weave peaking out. Then I fill coat to level all that out. Not sure it this is causing it. Maybe air bubbles?
My primary suspicion is that you have airborne dust (possibly from routing your finbox) and/or have been handling the board with your bare hands.
I’ve tried a number of different epoxies over the years and of them all I had the most trouble with the RR, Additive F or not. I know a lot of people swear by it but i always found it to be more hassle overall. I’ve been using the epoxy that Surf Supply sells (Apex) for several years now and have had good results every time. And no, I don’t much care where they’re getting it from.
I think you’re right and I say this because one thing changed in the past 6 months: my PTAC. With previous builds it just so happened that the ambient temp was within range of the resin requirements. These past two though, they were not. So I had keep the PTAC on which blows a fan periodically which would kick up dust. I hadnt expected that resin would be as sensitive to this as say, auto paint or fine wood finish. Im glassing this week so I’ll leave the fan off this time and see what happens. Will report back here with results. Thanks man
I’m betting either contamination from touching it with your hands, or humidity. Or both.
RR is great stuff, but compared to poly it’s even less lenient to bend the rules with.
My advice, become a completely obsessed about not touching the board with your bare hands anything past the rough shaping stage. Before any resin work - Vac it off, blow it off, and drag some tape down the board especially before glossing.
Don’t use shops rags to dust it off - the fibers wreak havoc. Also don’t start using chemicals to wipe it down. Chemicals start opening other cans of worms - especially when doing color work or pin lines.
Again, become obsessed about not touching it. I believe most of these issues will go away.
The space you use for glassing is another possible source of dust, expecially if you’re doing any shaping or routing or sanding in the same space you’re glassing in. I work in my garage (literally). So when I’m done shaping I blow everything off, sweep everything up, wait a few hours and sweep again. I never glass on the same day I’m shaping, and any secondary work I do on my patio so as to not contaminate my glassing space. Nor do I blow a fan into my space while I’m glassing. If I use a fan at all then I usually crack my garage door and set a fan to blow out from the bottom with additional outside air coming in from the top.
Are you warming your resin at all. Do you microwave the Part A. It sure makes it easier to spread and brush. Takes a little experience to get it right, but I prefer thinned over thicker. I think Gdaddy’s right about the dust. The only time I have had pin holes was when I didn’t get my surface clean enough or the resin was too thick.
The obvious cause would be contamination of the surface from your skin. Beyond that if the OP has done everything else right there is the slight possibility that he is experiencing some amine blush. Even though the resins these days are mostly blush free they will all create some blush if its too cold or too humid. Just a thought.
Assuming it’s EPS are you sealing the blank? When you said 2 capfuls of Add F is that in the fill coat batch? That’s a lot even for hot coat. Did you use Add F in the lam? Could you be pulling too much resin out of the lam or that area was dry (didn’t let resin soak in there)? You have got to develop a feel when squegeeing because there are areas sometimes that need more resin than others due to the surface below. Then the fill coat soaks in that area.
Thank you all for your replies. I left the PTAC/fan off and the problem didn’t occur, back to the nice smooth bone white surface. I can only conclude that this was the culprit.
