I am new to resin infusion and don’t understand why in some of the videos I’ve watched guys lay down carbon fiber, peelply, then perforated release film, then flow media and of course bagging material last.
I don’t get the use of the perforated release film over the top of peelply. Aren’t they both basically the same thing? Why use both?
The preforated plastic is an aid to pull the mesh off. I’ve done it both ways and without the pref plastic it’s a pain to get the mesh off. I kept reading about using it and talked to DDC and Design bikes and tried the plastic with the larger holes. It didn’t slow up my resin front but really helped in pulling the mesh off. Hope this helped.
I use perf release film to pull the flow media off much easier. And it helps degassing the resin at the flow front. That are the two benefits I realized. I prefer films with holes every 1/4inch.
But why you pull off separately mesh and peel ply? are you re-using mesh?
Mesh can not be reused. It’s easier to pull of the part the mesh when using perforated than when not using it. In flat surfaces might not be a problem but is tricky molds with perf really helps
Also, sometimes it is preferred to remove the vac bag and transfer media while still leaving the layer of peel ply in place. The perf plastic layer allows for this to be possible.
In some instances you may need to leave the peel ply on to protect the laminate underneath from handling, contamination, transportation etc.
In some cases (like building a boat) you may want the peel-ply to REMAIN on the part (for protection) while working on other things. Using the Perforated Film allows the superfluous expendables to be removed while still protecting the part.
I once pulled mesh and peelply out of a boat (no release film used) with an overhead crane…
I prefer using a P, P1 or MP22 styled perforated film. Even breadwrap will do.
Sounds like it is a good idea to use both if nothing else it makes life easier and if it helps degas the resin like DD claims then it’s a win.
Thanks everyone for the help.
I was wondering how perf helps degass the resin???
I would imagine the perforated holes act as a cheese grater, opening the resin as it passes by, allowing any trapped air to escape and be evacuated by way of vacuum.
???
Correct. And the resin always has a few mm to flow before it can travel in the fabric through a hole, so while this short time the air can travel to the front and will be transported away.
I’ve wanted to use a crane one some 70x70cm flat panels. Some times, coated peel ply does NOT come off. Depends on the resin, and flow media :-/ I’ve actually tossed a few panels due to that!
I definitely haven’t used a crane, but I did use a forklift at one point for the same purposes haha… also working on a boat.