help with copying sculpt from ultra cal mould

[Roydraven]

Hey everyone I have ran into a small problem with my mold I'm not happy with a torso mold I just made it hasn't got the arms on it
and I want to have them on it so it turns out better and I won't have to attach them on,well I thought of a small plan
I want to copy my torso with some rigid foam R-FOAM 100 Rigid Foam pouring the foam into my ultra cal mold copying
the torso so I can then sculpt my arms onto the torso and take another ultra cal mold of the torso is this possible to do???

 

[MEANGENE83]

Here is what I had plans to do.

It is similar to your situation.

I was going to take my ultracal mold and spray the inside surface with clear coat spray paint, to seal the surface of the plaster.
Then I was going to brush in a very thin
Layer of wax to act as a mold release. From there I was going to choose a semi rigid expanding foam from smooth-on and fillit up. Producing an armature of sorts to resculpt on.

Choose an expanding foam that is flexible enough to remove safely from the mold. But is also rigid enough to sculpt on.

Goodluck

 

[xdmray]

hey gene, wont spraying the plaster mold ruin it for latex casts? especially since you are coating over that with wax. i think the wax wont pull the clear coat off the plaster. then the porous nature of the plaster is ruined... i haven't done or heard otherwise, but it seemed a tad worrisome to me.

 

[Roydraven]

thanks for the advice MEANGENE83 I'm going to go ahead and use the rigid foam I have and go for it
I'll post pics if I succeed or not hopefully I do I'm just waiting on some mold release to release
the foam from the ultra cal mold when I do it XD

 

[ptgreek]

dude ..release the hell out of it ..if it sticks ..it will lock that mold tight ..especially with rigid foam ..also..remember that rigid foam needs alot of air to cure or you will have a sticky mess. Now one way around it may be to run a latex skin and use a fairly rigid (8 or above ) polyfoam to fill it up. the latex will be the barrier between the foam and the stone. It will also preserve the detail of the sculpt better then just foam ( air bubbles, etc). When pulled, you can use alginate to make a cast of the torso, just like a life cast ..back it with plaster bandages ..do one side first..let it dry..then vasaline the edges and do the other side creating a shell. After you can do a Hot clay pour into the mold sticking an armature pipe inside the clay as it cools .You will have an exact clay duplicate of that torso that you can even sculpt more into. I know it seems like alot of work...but it will be much easier to put back into stone later.

BTW .this is the type of release you will want to work with foam...paint it generously all over your mold if you are really gonna go just the foam route. If you go latex ..just powder the mold with baby powder first.

here is the release link. Its from Burmans...but you can do a google search for something comperable

POLYFOAM RELEASE

 

[Roydraven]

thanks again for the advice George what I want to do is really use the rigid foam as an armature to sculpt the arms back
onto the torso and fix the mistakes from a poor ultracal cast then make another mold from the foam and clay arms
with ultracal again so I think it might work I'll give it a shot I've ordered a release agent for my rigid foam
jwax the foam is R-FOAM 100 Rigid Foam I'm not sure of the hardness but I have experimented with it I think it is rigid
but not really that rigid it has a little bit of flexibility to it.
wait so if I use latex to make the latex release I powder the mold with baby powder am I suppose to use that
every time I cast latex with an ultra-cal mold???

dude ..release the hell out of it ..if it sticks ..it will lock that mold tight ..especially with rigid foam ..also..remember that rigid foam needs alot of air to cure or you will have a sticky mess. Now one way around it may be to run a latex skin and use a fairly rigid (8 or above ) polyfoam to fill it up. the latex will be the barrier between the foam and the stone. It will also preserve the detail of the sculpt better then just foam ( air bubbles, etc). When pulled, you can use alginate to make a cast of the torso, just like a life cast ..back it with plaster bandages ..do one side first..let it dry..then vasaline the edges and do the other side creating a shell. After you can do a Hot clay pour into the mold sticking an armature pipe inside the clay as it cools .You will have an exact clay duplicate of that torso that you can even sculpt more into. I know it seems like alot of work...but it will be much easier to put back into stone later.

BTW .this is the type of release you will want to work with foam...paint it generously all over your mold if you are really gonna go just the foam route. If you go latex ..just powder the mold with baby powder first.

here is the release link. Its from Burmans...but you can do a google search for something comperable

POLYFOAM RELEASE