Resin Degassing Time

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#1

Hey guys,
I’m continuing to cover all angles step-by-step for the infusion process. I had a question regarding the degassing of resin. Since I purchased a lot of polyester laminating resin, I figured I would use it. I’m in the process of picking up a 1 gallon resin/degas chamber and was wondering how long does it take on average for polyester resin take to degas? I’m looking to degas no more than 6-10 oz of resin at a time. I ask because when the resin is mixed with the MEKP, I have about ~10 minutes before the resin starts to thicken and ~13-15 minutes it is already gelling.

Thanks in advance

#2

Take into account degassing will shorten the resin pot life , sometimes even half time

#3

Same is in the bag under vacuum.

#4

So I guess there’s no way around it? I just have to be quick. I was thinking of maybe using hot water to degas, but the heat would also speed up the chemical reaction.

#5

10 mintues…? How much MEK-p are you adding? Just reduce the amount till it suites your needs. I forget the minimum amount but maybe like .75-1% of catlyst. The nice thing about polyester is you can tweak the pot life.

And are you degassing because you’re infusing? Is it a wet layup? Another thing to consider is to be more careful when mixing to avoid entrapping bubbles in the resin.

Degass with water? I don’t think I’ve heard of that before, how do you do that?

fiberpro: how do you figure that vacuum reduces pot life? You mean because you’re spending time to do the degass, you’re losing pot life right? And under it bag the gel time should be significantly more because of less mass exotherm. Resin will always gel faster in mass. This is why you want to get the resin out of a cup and into your fabric asap, so you have more time to work.

#6

At work, we use and old chop gun system, with a plexis mixing nozzle, to catalyze the resin,then pump in into the container with the feed lines.