My question in this:
in flat molds, can i use a heavy Weight, sitting on the carbon layer
(and on the carbon layer itself - some cloth to Absorb the access resin,
instead of putting it in a vacuum bag?
how much pressure does it need in a vacuum bag usually? (in psi)
and What’s equivalent it in Kg? (conversion psi - Kg)
Vacuum generates some 9500-10000 kgs of weight per sq m.
I am very interested in this technique. I have been making flat sheets in a flat mold with weights but have never used cloth to absorb excess resin. Can you please explain what cloth you use and the technique a bit more please? My sheets always come out resin rich but I’d have thought a cloth to absorb resin would bond to your part.
Mould
Laminate
Peelply (optional)
Perf film (P3, P31)
Bleeder (a nice even one, like Airtech Econoweave 22 or 44)
Protective film
Board (wood or so)
Weights / clamps
so, what i understand is, that this is POSSIBLE. if i take my car (1000 KG) And put it on the mold (with a flat surface on it) IT SHOULD WORK!
If your mould is flat, yes. It shows the force vacuum generates.
If your mold top is VERY stiff. Else it will warp under the point weight of the wheel contact point.
Use a big steel beam (or piece of railroad track, etc) and park your car on that to distribute the load. Remember that you’re only getting a portion of the car weight if you use one or two tires. If you use all four tires then please send us the picture!
Or better yet… make a cheap DIY vacuum bagging system out of some poly sheeting, caulking, and a fridge pump and get the same results. Google how to make such a system. And make sure to watch you don’t catch the pump on fire from running it too long (do in a safe place in case a fire starts).