Hey guys,
Forgive my beginner question, but I’ve read on here and in one of the books I’ve been reading that you can wrap the spiral tubing in peel ply. Still on its way here, the peel ply I ordered was the Airtech Bleeder lease B peel ply.
My question is, does that mean only resin will be able to travel across the peel ply and into the mold? So air bubbles will remain inside the peel ply? Kinda like a cheating way of getting around degassing?
Thanks a bunch
Negative. The peel ply around the spiral wrap ensures vacuum continuity, so flow is not impeded. Also if you’re using a vacuum bag that is easily punctured, the peel ply can help protect it from the sharp edges of the spiral tube.
If your resin is flowing in though the spiral wrap and you have only peel ply between the inlet spiral and your laminate then the resin flow will be 100% impeded from going anywhere fast other than through your spiral wrap.
The inlet piping or medium must have a decent contact and flow path to get into your laminate and any core or other flow mediums.
Some (including myself) will use peel ply only in contact with your outlet side vacuum channel/spiral tube/or other so that the resin front will near stop at your vacuum perimeter without filling your vacuum channel/piping/plumbing/spiral wrap.
It’s called a peel ply breaker.
Hanaldo is incorrect as the peel ply only will maintain a vacuum continuity, it’s no good for resin flow if your talking about having peel ply only on your inlet side.
I disagree totally with this. ^^
I always sandwich my resin line (spiral wrap) between peelply as a way to remove excess resin from the laminate once infused/cured. There are NO issues with resin transfering to the laminate through the peelply that I have experienced. This is a well known and used process across a number of industries
A simple test you can do yourself. Paint the resin your using on one side of your peelply and touch the other side. Is your hand sticky? Then the PP is resin permiable
Of course there is no issue with resin moving through a peel ply to a laminate directly behind it.
From the original post I am assuming that this guy is intending to let resin in a spiral that is wrapped in peel ply and I have assumed it may be on a flange and not in contact with any laminate, yet. Just a flange with spiral wrap and few a inches to travel to a laminate through only peel ply will not work. The way the poster is asking about resin travelling across peel ply (as opposed to going through it) and into the mold makes it sound like this is on a flange. Is there a laminate there too??
If the spiral is directly on the peel ply that is also on the laminate then that will work.
For Turtle, of course peel ply is permeable but peel ply alone will not flow the resin with sufficient speed.
The original poster needs to clarify his laminate sequence and layout etc.
There are some reasons to wrap the resin inlet spiral in peelply.
1: You prevent that you spiral can damage/puncture the bagging film.
2: The resin can not exit the spiral that fast. So if you have a longer inlet line and you wish
a more consistant resin distribution over the length this can be done by wrapping the
resin line in peelply.
3: The resin feed spiral can be removed easier.
If the vacuum spiral is wrapped this is done to save the bag. It will not really stop/brake resin traveling into it. Therefore you can build a brake zone to lower resin entering the vacuum
line.
Sorry guys. To clarify this is how I plan to set it up. Gonna use the spiral tubing for the resin inlet and outlet. Both wrapped in peel ply and both on the top of the green green infusion flow media (mesh). After fabric, gonna lay down peel ply–> infusion mesh–> vacuum bag. The part is flanged. Hope this helps clarify things
To place the feedline on top of the flow media is fine. But do not place the vacuum
line on top of the flow media!
Let the flow media end about 2 cm before the fabrics end. Place the flow media about 2-4 inch away from the end of the fabrics and connect part and vacuum
line with peelply.
You can also read the MTI hose thread, (independent from the product) there are all information you need for a sucsessfull infusion.
The peel ply on the inlet can also act as a filter removing any floaters such as dust and dried bits of hardener from entering the laminate.
It can also trap some air. I never have nor will degas and I find that it catches tiny amount of gas that is generated.
Apologies, my post was misleading. I meant that it does not impede the flow of air in the vacuum channel. Then with regards to the inlet, I wrap mine to protect the bag, though I haven’t had any issues with my bag being punctured when I don’t do it.
Wasn’t intending it to sound like it should be used on the inlet instead of or without flow media.