Caulk as a mold shell?

Hecubus114

Hecubus114

Sr Member
RPF PREMIUM MEMBER
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!
 
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!
 
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)
 
Last edited:
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.
 
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.
 
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.


Hecubus114 said:
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!
Click to expand...
 
This thread is more than 13 years old.

Your message may be considered spam for the following reasons:

  1. This thread hasn't been active in some time. A new post in this thread might not contribute constructively to this discussion after so long.
If you wish to reply despite these issues, check the box below before replying.
Be aware that malicious compliance may result in more severe penalties.

Similar threads

HighlanderFX
Face Shell for Michael Myers mask
Replies
0
Views
413
HighlanderFX
HighlanderFX
helix_3
How will expanding foam fill this hypothetical mold?
Replies
4
Views
639
helix_3
helix_3
helix_3
Thoughts on this two-part composite mold workflow?
Replies
2
Views
379
helix_3
helix_3
ilBrutto
Construction Question - Hard Shell Case
Replies
4
Views
701
ilBrutto
ilBrutto
scathe
"replicating" a prop that never existed, from a novel...
Replies
3
Views
231
scathe
scathe
Back
Top