Just finished sanding hotcoat on Carbon fibre topped short board, Never noticed before but seem to have little air bubbles all over the surface which is highlighted by the black carbon, has anyone had this problem with epoxy and are there any solutions, cause makes the finish look pretty crappy…
Thanks
I have had this problem when coating wood with epoxy but the bubbles were comming out of the wood cells. It might be caused by dust or over zealous stirring. I solved the problem on hotcoats by warming the resin to reduce the viscosity which allowed the bubbles to rise to the surface and burst before the resin was too thick to flow out and fill the resulting “holes”. Trouble is that the resin is almost too runny for easy hotcoat application…It worked for me.
Yes and yes.
Rikds hit the nail on the head. heat resin a little before adding the hardner, don’t froth the resin stur it, dont over work it on the board, let it soak in in its own time before pulling resin off.
Heres another tip.
You may notice you get more “ghosting” on the lap over dark colours if your pulling resin off the flats to saturate the hanging cloth. If you wet and fold the lap with a 4" brush before you pull off the excess resin you will eliminate the problem.
(unrelated but) I was also experiencing a problem with getting roving (for fins and leash loops) to go clear, it would always be a bit “milky” I scratched my head over this for a long time, then I ran out and ordered new roving and it stopped happening, all the time it had been the roving and not the resin at all.
If the carbon has a big weave pattern (like 6 oz cloth), a lot of the bubbles can come out with a heat gun after you tip it off. It’s just essentially the same thing as heating the resin before mixing, but instead after it’s on the board and agitated by the brush bristles/foam… You’ll see bubbles popping everywhere, some you didn’t even know were there.
I do both.
JSS
-small paint roller, squegee is not easy to use efficiently and bubble free
-clean the board prior to hot coat, any grease, grime or dirt will cause trouble
-warmer resin is more liquid than colder resin, however cooler, thicker resin is less likely to develop bubbles in the first place
MM
be careful not to over do it with the heat gun, and watch for dust and bugs being sucked into the air intake and blasted on the the board, thats why I stopped doing it that way.
MM
be careful not to over do it with the heat gun, and watch for dust and bugs being sucked into the air intake and blasted on the the board, thats why I stopped doing it that way.
ROFL!!
excuse me… I just had a vision of “da supa fly” gettin sucked into your paint striper and getting spat out on a fresh gloss job!!