The last two board I’ve glossed have had these strange ‘lumps’ appear on the board almost immediately to pouring the resin. I’m using PU/PE. I know they’re not zits because it happpens so quickly, and they’re much larger,harder, and profound. My initial thought is that’s some catalyst instantly cures some of the resin when I put it in, although this seems unlikely. I’ll start to see them midway through my gloss coat application. And then do my best to carefully pick them out with a razor blade before in kicks. I am glassing in the same space I shape in, so I know there’s some dust in there, but I wait at least 20-30 minutes for it to settle before I shoot the gloss. Here’s some pics, what do you guys think?
Btw I am using a fresh bucket and stir stick and brush. Did an acetone wipe down before. I’m using the gloss resin that takes forever to kick (forget the name). And I catalyzed 2% (cold that day and hadn’t pulled out the heater yet)
Strain your resin - on a fresh brush pull the bristles to get the loose ones out.
When you say fresh brush do you mean brand new, never used or new when you did your hotcoat then you used it for your gloss?
By the pic I’d guess little pieces of semi-cured hotcoat left on your brush.
Wipe your blank down with tape.
Add a splash more of sa to get a little better flow out.
Resin should take about 2-4 mins to lay down and about 15.
Others may have more info.
Brand new brush, never used. I pulled the loose bristles out with tape as usual. And yeah it only takes like 4-5 mins to lay it down
Might be temperature related? I have have those as well on my last fill coats, when it was maybe a wee bit too cold. I was using epoxy though.
Strain your gloss resin before catalyzing! I use those conical paint strainers and they seem to get those little chunks out pretty well. As to what those little chunks are, I dont really know. Maybe impurities in the resin that come straight out of the can.
Okay that’s probably it, I had a strainer but it was dusty so I figured that wouldn’t help much. Thanks guys
Could still be contaminates from the room and in the air. I have stopped sanding in the same room as I glass and it has helped with this issue for me. I also now strain my gloss coat and keep the air as still as possible when working. Clean that board as good as possible and you can use a tack rag as well. I do sanded finish boards anyways, so if I do get any little bumps they sand right out for me. The boards are more about function than anything else for me. But having a nice clean finish is good too.
Looks very much like old resin. When it gets old, gloss resin will get clumps in it since the styrene/wax solution gets hard first.
Straining is always a good idea, but I’d say that batch of resin is on the way out.