Vacuum and Seconary bonding.

General Composites Discussions Composites Talk
#1

Basically what I want to do is lay up 3 layers, vacuum it down, wait till it starts to gel… (2 hours). Then remove the bag (its re-usable) and lay up 3 more, and repeat the cycle untill I have a total of 9 layers. Then after the 9th layer let the layup cure. I do realize I will need 2 types of peel ply/film for this. Very porous for the first six, and then film for the final.

Have any of you tried this? And how bad will it effect the overall strength of the final product? (assuming the 1st 3 layers can stay uncured for the duration of the lay up).

Reasons: The main reason why is that I figure laying up 3 at a time will reduced the chanc of developing/trapping bubbles.

Also the mold is large (keg size), has several sharp curves, and needs a few cuts in the cloth to prevent bunching and ripples.

The cloth we had been using was 10oz plain weave and laying up all 9 in about an hours time (with marginal success). The cloth we tested today was 10oz satin. It layed down WAY better, but, held more bubbles even after rolling and squeeging them out. Wont know the finish untill tomorrow.

Ideally I would like to kill the last 3 layers and lay up only 6. But its not my dicision.

#2

well you are going to generate a lot of heat by doing it this way! Iv’e never done anything this way so I can’t give a good educated guess on your turnout

#3

you can do that…

Your peel ply negates the need for sanding and scuffing the part to add more layers.

All you are really doing building thickness. Most stuff that starts to cure will be cooled to room temp by 2 hours time.

I cant see why you wouldnt do that. Id be doing the same thing if I needed a way to build the part and had issues with my layup in bulk.

#4

Awesome. Good to hear it will work.

Although we did solve our problem yesterday. We switched to the smallest radius aluminum rollers we could find. At first we bought them to smash the joints in. On satin weave they work perfect for rolling bubbles out (while on the mold), and suprisingly they dont push much resin out.