Hi,
When all your fabric is cut to size, you need to weight it. Then, ideally, you would want 40% of this weight in resin. BUT, keep in mind that your resin feed line, infusion spiral, distribution mesh etc will consume resin too.
So mix a little more resin that what the fabric layers should take.
Breather material is not needed if you go for the infusion. Usually in infusion, the stack is: mold, release agents, fabric, peel-ply, distribution mesh, vacuum bag.
Breather is used when you hand wet your fabric in your mold and then put it under vacuum. Breather will act as uniform pressure distribution as well as soaking the excess resin thru a perforated release film.
The reinforcment should "stop" anywhere between your part flange (to have enough material to trim your part) and your gum tape. I usually leave fabric at 1 inch from part flanges, and 1 inch from the gum tape.
Hope it helps.
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