A few questions

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#1

Hi, this is my first post on this forum, so far it looks like an incredible resource! I have a few questions regarding layups.

I am using epoxy resin with carbon fiber and kevlar. Id like to use a clear gelcoat on the parts that have the weave exposed. Has anyone used a gelcoat with an epoxy resin? If not, what is a good technique for creating an epoxy ‘gelcoat’ on a mold?

My second question, has anyone used a FoodSaver vacuum device for their vacuum bagging? I am using an air compressor with a Gast venturi style vacuum generator. It works well but the noise from the air compressor is quite annoying. Even when using proper vacuum bags and tape, I can never get the bag to hold proper vacuum with the air compressor off. I came across a model rocketry website which illustrated a vaccum bagging technique by using the FoodSaver.

The FoodSaver I have also has an accessory jar which can be vacuum sealed, I think it will be a good way to degass the resin if the FoodSaver can pull enough vacuum.

Thanks for your help!

#2

Welcome and worth the wait to get in here?

Gel coat is a PER (polyester based resin) but there are face coats for epoxy resins. Revchem sells them…

But most all epoxy resins will yellow in time from the sun. Better to clear gel coat (PER) and then lay up with epoxy or lay it up, pull it and clear PUR it many times.

Is your air compressor oil or oil less type? If oil less…I can understand the noise deal!

You can get small vacuum pump ( I still have a few around here…) on the cheap…so why waste time with a vacuum bag sealer vacuum? I bet those might work for tiny parts but?

#3

you can use Duratec PE hi-gloss clear topcoat, or VE hi-gloss clear tooling top coat, I believe the product number is 905-45, 1905-45. works well with all the epoxies I have used with. just spray your mold 15mils thick, let tack off completly and then layup. you will pull nice finished parts out of the mold

#4

Thank you for the responses! Do you have any recommendations for an inexpensive vacuum pump?

#5

Robinair 15400 and 15600. Cheap, pretty quiet, and will pull a good vacuum (29").