Vacuum Bagging Help Please

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#1

Ok, if im using peel ply do i still have to use perf release film ? can i put a couple of layers of peel ply down or will one ply work just fine ?

Same with release film can i put a few pieces down ? (the parts im trying to make out of CF is a flat piece with a lip on it 50mm wide x about 200mm long so i just wrap the whole thing in release film etc because its only 50mm wide)

Breather cloth, is there a limit to how much you put down or does it not really matter ? ie is one layer too little if it gets saturated with excess resin ? or will too much breqather cloth make it difficult to drag air bubbles out etc ?

just a few pointers really or tips of do’s and donts would be greatfully recieved

Matt :slight_smile:

#2

personally,vacuum bagging is a bit freestyle. based on experience, you see what works and what not. it depends on the part too. i use peel ply on parts that will be glued on the car (for example) but because the breather when it gets saturated with resin it becomes one with the breather, its a real bitch to pull off the part. so in my last parts, i also put perforated release film. with that, i was able to remove the breather easily, and pull the peel ply on its own.

you can put more than one layer of release or peelply, but i would go against more than two. dunno if it really matters.

#3

Many time I put 2 sheets peel ply in one part. No problem. About breather, Sorry I don’t have any idea because all my parts is through infusion system.

#4

For wet layup?
Peelply is only needed if 1: you need to bond parts together. it leaves a rough surface for additional adhesive to attach too. 1: if you want a perfectly smooth back. Sometimes when only using release, it might wrinkle alot. To some test pieces with your mold and see what works for you.
Perforated release is a must. If will allow some resin to leak out, while keeping most in the part. The breather on top will soak up the resin, so it has somewhere to go! (just the bag on the release film won’t do anything) Plus, it spreads the vacuum pressure over the entire surface. You can put peelply and THEN the release, and THEn the breather on…no problems with that approach. You can put several pieces down as well. Just overlap an inch so they have room to move while vacuuming.

#5

George, i’m just curious how it works for you…
do you use the flow medium under the peel ply or on top of it?

What brand of peel ply are you using? :slight_smile:

I have had some trouble with infusing thru peel ply, but it may just be the brand of ply i was using.

I was thinking possibly from now on, if the part doesn’t need post bonding, that i will use no peel ply… just leave the flow netting in the laminate permanently.

sorry for the derail :open_mouth:

on parts with curves or bends in them I have always found it good to cut the peel ply into smaller pieces in those areas so no bridging happens.

#6

[QUOTE=Fastrr;23477]
I was thinking possibly from now on, if the part doesn’t need post bonding, that i will use no peel ply… just leave the flow netting in the laminate permanently.

:open_mouth: for shame!!! that is like adding 50% more weight, and no strength to the part!

#7

nah it doesn’t add 50% weight unless the part is only two layers of 6oz carbon fiber :slight_smile:

Otherwise with the green Airtech flow medium trying to force resin thru peel ply ends up with dry spots. Thanks to CarbonJoe, I have some red flow netting now that i want to give a try.

I don’t think I’ll try Enkafusion after hearing that other guy’s problems. that and it just looks funny, but who knows maybe it works better:confused: