How many liquid ounces of PER does it take to fully wet out 11 ounces of fiberglass mat? I’m making a mold and don’t feel like breaking out the nice clean scale to measure PER weight. I know… i’m lazy lol.
I ended up using 22 liquid ounces of PER for the 11 ounces of weighed mat. I’m sure the mold is resin rich:o I was in a hurry to get it done. I did use a ribbed aluminum roller to work out as many of the air bubbles as possible with each layer of mat applied. I tried to be as thorough as possible with removing the air bubbles, and making sure each layer of glass was completely wet. I tried Perveng’s idea of using a layer of 3 oz s-glass cloth as the final layer. Hopefully that will make handling the mold easier. Working with glass sucks lol. It and per combo are messy.
Is there a resin for mold making that doesn’t require a reinforcment like f/g, c/f ? If there is such a thing, would the mold be able to make at least 15-20 parts?
I’ll let it sit for a couple days. Then i’ll de-mold it and trim off the rough edges of the flange. I’ll post a photo in a couple days.
This is a heel guard mold for motorcycle parts.
Maybe Silicon molding compound? Won’t need a release agent for that!
Else…aluminum 
On Mythbusters Sunday night they were making molds of scale model boats. They used a pourable molding material that I think might have been silicone or something similar. Would algenate(sp) the stuff they use in the special effects makup work? I’ve seen that reinforced with cheap materials like burlap etc. A buddy works in the movies in special effects and showed me his work.
Fast and cheap way to make simple mould is to use plaster. But if you want to make 15-20 units, of something like a pair of heel guards, then I cant see that making cfm moulds is likely to take more than a couple of hours at most.
either that or PER and profil…I have used that and it is rock solid and won’t crack.
Silicon is very flexible right? hmmm. may not work for what i do.
I’m thinking of switching from PER/tooling gel coat, to epoxy made for mold making. I think fiberlay.com sells it by the quarts. The stuff is kinda pricey at $38 per quart or so. That stuff had something mixed into the epoxy resin so it would make a good mold surface. I think the reinforcement layers are then normal epoxy and fiberglass. It doesn’t get me away from using fiberglass, but I think I can deal with that. I gotta respect my neighbors and PER has too much VOC’s.
Please forgive me if i have asked already, but if i recall i did not get a sound answer last time, no ones fault though.
I would like to know what compounds to mix into epoxy to make my own molding resin/ “gel coat”.
Thanks guys, I appreciate your help.