Caulk as a mold shell?

[Hecubus114]

I remember a thread a while back where Kwally used caulk as a cheapo mold - I was wondering what all your educated thoughts would be on using this as a mold shell? I have polyurethane rubber for the inside mold, but nothing for my shell. For something the size of a 1:1 head - how durable would this be? I thought about maybe trying a "caulk fiberglass" with strips of cloth covered with caulking... thoughts?

Kwally said he used expanding foam for his mold shell - but I dont see that lasting through more than 1 or 2 castings. I'm looking for something that will last longer. Your thoughts are much appreciated!

 

[ob1al]

I think decorators caulk wouln't fare well. Messy and weak.

Why not just buy a little bit of FG and resin and go with the tried and tested method for a mother mold? It can be very inexpensive for such a small amount and the bonus is, you know already that it will work fine!

 

[Hecubus114]

I know FG is the better choice - I actually have only used it once and it turned into an ordeal for me for some reason... huge mess and didnt cure properly in some spots. I want to try it again but dont want to risk ruining my current project. My usual stuff is Plasti-Paste, but that gets mucho expensive especially with shipping (at least on my budget). I was hoping there was some alternative that I could get locally and in just the amount I need (which I know, fiberglass is the obvious choice - but I'm scared to touch it again, LOL)

 

[ob1al]

I know what you mean, I have used it for years and still hate the stuff. It's horrible.

I've tried expanding foam - quite rubbish. Tried bondo/body filler and that worked a bit better but it's probably more expensive than a small bit of FG and resin from the local car body shop/Halfords.

Unfortunately, as far as mother molds go - at least ones which will last - FG is the only way to go, in my experience.

It's a bummer, but just wear gloves and work in a well ventilated space.

 

[MrGzilla]

i used expanding foam for my mothermold for a majoras mask that i made for a friend and it has held up pretty good. and if the foam dodent hold up its easy and cheep to make another.

 

[SwampDonkey]

Your best bet would be to head over to walmart and get a small thing of fiberglass resin and a pack of glass mat. Should be about 20 bucks total.

I remember a thread a while back where Kwally used caulk as a cheapo mold - I was wondering what all your educated thoughts would be on using this as a mold shell? I have polyurethane rubber for the inside mold, but nothing for my shell. For something the size of a 1:1 head - how durable would this be? I thought about maybe trying a "caulk fiberglass" with strips of cloth covered with caulking... thoughts?

Kwally said he used expanding foam for his mold shell - but I dont see that lasting through more than 1 or 2 castings. I'm looking for something that will last longer. Your thoughts are much appreciated!