I've just infused my first test piece, a carbon/foam sandwich using your IN2 Infusion Resin and I am seeing *a lot* of outgassing from the resin under full vacuum. Small bubbles are visable within the within the resin transfer mesh and continue to form/appear as long as there is a hard vacuum. Will this compromise the strength or the cosmetic finish of the finished part? (I haven't de-molded yet.) Is there any way to elimitate outgassing?

Thanks,

Phil.

Hi Philip,

Epoxy infusion resin (such as our IN2) will not boil, even under a total vacuum. Polyester, acryllic and vinylester infusion resins can and will boil but epoxy will not. If you're getting air bubbles forming away from this 'front line' of the resin then something is wrong somewhere. When you say there is no leak in the bag could you let me know how you confirmed this - did you perform a 30 min drop test?

Regarding clamping off both lines or only the resin feed line (and the difference between the text guide and our video tutorial), both of these methods are correct but will yield different results. In the video we're trying to show something very specific which is how to do a resin infusion specifically for a *perfect surface finish*. To get this purfect surface finish you actually have to perform the infusion slightly resin rich (which is to say slightly more resin that the minimum that the reinforcement can support). By having a slight (maybe 5%) amount of resin above the minimum you should not get any pin-holes on the surface (where the nodes of the fabric intersect). This was the trick we wanted to show in that particular video.

In the text guide, we describe the traditional infusion process where the vacuum line is never clamped off (and in fact keeps pulling at the bag for the duration of the cure). This method will result in the lowest resin-to-fibre-ratio but will almost always result in tiny pin-holes on the surface of the laminate (which most people have always accepted).

Like I say, neither is wrong or right, they're just targetting different priorities. For the lightest possible laminate, keep the pump running and never clamp off the vacuum line. For the best surface finish, clamp off both lines at approximately the same time, which will leave the laminate slightly resin-rich, and then switch off the pump.

--Matt

Matt Statham
Easy Composites / Carbon Mods - Technical Sales

I've just been out to the workshop and the vacuum gage has dropped from -1bar to around -.8 overnight... so I do have a leak after all. I only did a short (5-10min) vacuum check before introducing the resin (impatients I guess.) Lesson learned - I'll perform a full 30min vacuum integrety test in future.

Apologies, mea culpa!

Phil.