Hi all,
So I have a couple molds I am using and I have started experimenting with divinycell 80 (1/8 inch) and also airlite pvc 1/8 inch in my layups. My layup consists of a couple layers of carbon then 1 layer 1208 DBM biaxial, followed by 1/8 inch foam core, 1 more 1208, and another carbon to finish it off.
Lets say I would prefer to do a 2 part vac bagging session just primarily to make things easier. Which process do you think would be better?
carbon, carbon, 1208, divinycell - apply vacuum
then apply 1208, carbon and vac bag again
or
carbon, carbon, 1208 - apply vacuum
when it dries use some sort of epoxy film to glue foam in place, then add 1208, carbon and vacuum the rest?
If I were to do the second method, what is the best method for gluing/epoxying the foam in place?
First of all, the layup needs to be a mirror image on each half of the laminate midpoint, in this case it would be the skins on each side of the core. CF, CF, FG…core…FG, CF, CF. That’s one of the basic starting points for designing/producing a proper composite part, but now back on the original topic.
What I’d recommend, is to do plies 1 and 2, peel ply, bag it and cure it. Then layup ply 3 (which will act as the adhesive for core-to-skin), core, plies 4, 5, 6.
No need for peel ply again if nothing will be bonded to the back side, just release film, breather, and bag it.
Were you planning on wetting out both surfaces of the foam core? I thought foam core got it’s strength from being wetted out with the rest of the laminate? Just asking.
I’m with Fast on this. how are you putting resin in the part? I would think it would be easy to do all layers if infusing or prepregging. if you have concerns of the core shifting, then use small amount of adhesive spray? Even a wet layup, do all layers if you can, squeezing out as much resin as you can before bagging.
Unless you have core made for infusion, it’s not going to work.
By curing the tool side skin alone, print through is kept to a minimum from the core edges and less heat from a thin laminate.
The reason I only had one layer of CF on the inside is because after I pop the composite from the mold I have to put in various mounts and such, then they will be secured in with additional layers
My mold has some curves in it (~4 in radius curves) and so I found out that the scored foam works best but even with the scoring, it is still difficult to keep it laying down with wet epoxy under it alone.
Should both surfaces be wetted out at the same time? Or can you bag one, then wet out the other side and continue?
I am not using VARTM or anything, I am placing resin simply by pouring it in and using squeeges/brushes. I initially was going to use infusion, but i was concerned about the correct port locations. I agree though it would be nice to use that method.
I will be using Airlite pvc foam mat 3.5 lb.density 3.5mm thickness
Back to my original question about the epoxy film, check out this link below, this is what I was referring too. Not sure where they get it, but it looks like it would work rather slick.
I would go with what TET says about print thru. I just thought it would be simpler to lay it all up at once, but perhaps that is not the best way?
I wonder if that epoxy film can be used as a surface coat on the part? I am sidetracking the thread a little here… My thinking with this is to prevent pin holes, pits etc by using the epoxy film as a sort of “gel coat” on the waxed mold surface. Think this idea would work with good success?
