Mold Making and Casting: Casting R2 Rigid Foam

Here are 2 methods for achieving a good matte, paintable surface on rigid, urethane foam. Both baby-powder and primer (sprayed into the mold and allowed to dry) may be used to create a cast part with a matte surface for easy painting. New Prime-it primer may also be used to simplify the painting process.

Category:

Howto & Style

Tags:

• primer
• prime-it
• mold-making
• moldmaking
• casting
• plaster
• resin
• rubber
• silicone
• rigid
• foam
• prop
• making
• mask
• special
• effects

[guzzlingas1]

Can this foam be used for lost foam metal casting?

[brickintheyard]

@guzzlingas1 I am not familiar with that process.

[TheSaltysack]

how strong is this foam and can i build rc planes with it.. is it light weight

[brickintheyard]

@TheSaltysack This is a fairly strong foam but I would still recommend using a resin skin over the foam. EZ Flo 120 works very well for this.

[duploman1000]

4:00 Eww..

[brickintheyard]

@duploman1000 Eww indeed. 

[alphanumericPhrase]

@brickintheyard lost foam casting is the process of putting a foam shape in some sand then pouring molten metal on to the foam (through a small hole). the metal effectively vaporizes the foam and you end up with a metal casting in the same shape as the foam was originally.

[brickintheyard]

@Riddlemind Depending on how flexible you want the part to be, use EZ Flo 60 or any of the flexible to semi-rigid PT Flex materials.

[Riddlemind]

Which products would you suggest if I wanted to make big rubber real looking swords, shields, axes, flails, etc?

[brickintheyard]

@DDofCourage Never used it that way but I don't see why not. We have had customers make resin masks before also.