Issue with micro bubbles stuck between carbon threads (pictures)

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#1

I’ve been having this issue with little micro bubbles getting stuck between the threads of carbon, but only on parts with an IMC. Picture 1-2 show the issue close up. Picture 3 shows the issue overall. These are all from a part that is laid up over a clear IMC and done by infusion. The last picture is a close up of a part laid up direct against the mold surface. Same infusion epoxy, same setup, same cure temp, same everything. I’m just having a hard time figuring out why parts with the IMC are giving me this issue. I have never had to de-gas my epoxy (the last picture was done without degassing the epoxy and it looks fine) and I did already try to degas the epoxy on another part and didn’t turn out any better. Any help would be appreciated.

IMG_2529 by AJ Hartman, on Flickr

IMG_2528 by AJ Hartman, on Flickr

Overall you can see it makes the part almost look “cloudy”.
IMG_2530 by AJ Hartman, on Flickr

Here is the part laid up just against the mold. No IMC on this one.
IMG_2531 by AJ Hartman, on Flickr

#2

What is the potlife of your resin. I´ve had similar problems with slow epoxy resins (6 hours potlife) and imc. When I added a faster hardener to the same resin the problem never occurred

#3

Also what imc are you using? Maybe it’s some type of reaction that occurred over time and a faster pot life doesn’t let the reactions set up?

#4

How sure are you that you didn’t have a leak? I’ve had similar results before, but it has always been in the presence of a very tiny leak. Could it be coincidence that the result without an IMC just happened to not have a leak? Seems extremely unlikely to me, but it’s a thought… My suspicion is that it is something more along the lines of your IMC not being fully cured and there’s a degree of outgassing going on. What IMC Are you using, and how long have you let it cure for prior to infusing? And what temperature are you infusing at? Have you warmed up your resin at all for the infusion?

Beautiful photos just by the way, what lens are you using?