Tiny air bubbles in Epoxy. Overlay

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#1

Hi all, i have been experimenting with a few overlays and making some small CF pieces from moulds, i have come across a problem where i haven’t been able to get any help locally.
In my overlayed pieces, tiny little air bubbles are forming that almost look like condensation on the of each layer. Temperature, humidity haven’t made a difference. I am using an epoxy R521 mixing to correct ratio with scientific equitpment. There is not air bubbles at all in the resin before i lay it and they only seam to appear after the resin is hardening up.

Anyone else had any similar problems/experiences.
Nat

#2

Here is a pic of the air bubbles, they look a little worse in the photo than what they do in real life. They only form right on the surface of each layer. I am trying a different resin tonight hopefully it will work better for me.

#3

Seems like it would be moisture in the resin or CF prior to catalyzing. 'Course I’m guessing. Could also be a bad batch of resin or catalyst. Again, just guesses.

I think you will fix the prob with new resin.

Maybe try and harden the old resin wihtout the CF and see if it happens. Just start eliminating variables until you get it.

Good Luck with the lay-up.

#4

Thanks mate will give that a Try.

#5

Are you vacumm degassing the resin mixture or vacuum bagging the laminate?

#6

No i don’t have the equipment to be doing any of that stuff, although i would love to.

#7

Thanks mate it appears to be moister contamination alright, thanks for the tip.