Is there a plastic that is suitable for composite molds?
Is it possible to pour a mold out of hard urethane that can be used multiple times, say at least 4 times?
I was thinking of making a small wood box open on one side. Then place the plug model into the box and pour urethane plastic over it.
www.polytek.com/ silicone and latex rubbers for mold making. Make sure you get a high shore else you can distort the mold under vacuum, or even gravity. One can back up a thin mold layer with a GRP shell, or even add cabosil/microballons/fiber into the rubber to strengthen it against tears.
What would be considered a high shore # for rtv and for urethane casting resin?
Which product have you used Riff and added fillers to?
i’d say 40a-60a…higher the better for unsupported molds. I have used cabosil (fumed silia) as a thickener. I have not used woven/chopped glass, but seeing how thick and sticky RTV rubber is…it will make it into a mega blobby mess. But I’m sure depending on your application, casting your part with layers of fine glass will help for tear resistance, then you can back it up with a plastic/composite shell to support the structure.
As them for a mold making guide. They sent one to me, and it explained so much about how rtv molds work.
I will put up some information regarding this in the future. Will include “how to” and where to find the right materials.
We use plastic molds to make prototypes or 1 offs. Can make a mold and useable composite part in 2 days.
I will wait eagerly