Prepreg roll partial consumption

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#1

Hi everybody

I think this a pretty stupid question but wonder how you deal with the issue.

If you are going to use prepreg you need to get it out of the fridge and keep it at room temperature 24 hours in a sealed bag to avoid condensation before using it.

If you re going to use only a small part of your roll how you handle this?
Do you take it out of the fridge break the sealed bagged cut of you piece you are using put it in sealed bag and repair the main sealed bag of the roll and put it again in the fridge while keeping the prepreg you are going to use at roon temp for 24 hours?

Thanks

As you can see i am a newbie on prepregs.

#2

Wait for the roll to come to RT, or at least stop condensing. Cut the piece, throw the sealed bag with desiccant back into the freezer. If you are going to do similar parts, or at least size parts, you can always ‘kit’ the prepreg, by cutting the plies as needed, sealing each part kit in a bag, and just pull each kit out as needed, so the rest of the prepreg doesn’t have the thermal cycle of thawing. If you KNOW you won’t use anything larger than say, 24"x24", just cut lots of squares at once. Or if you have templates for a part you know you will be doing, cut them, and bag them.

#3

Ok. That means once to get it to room temperature partition the roll and putting the partial rolls again in the fridge.

Are the new bags required to be sealed under vacuum?

#4

rolls/kits. yes, but this way you can pull the partial amount out, and the total out-time for the roll will be less.
You don’t have to seal under vacuum, unless you do just a tiny amount to get the extra air out. Get a can of desiccant packs and throw the right amount of packs in the bag, you should be good.