silicone bust

Just wanted to ask advice as I have never done silicone before
my question is does the silicone bust have to have a support
liner once the silicone is poured, also as a test what silicone
can be used seeing as its a bust and not for skin contact
could I use soft RTV as a first pull before I use platinum or
is there a silicone that compairs in price..

 

Do you mean a Fabric Liner. If so No it doesnt need a liner but it needs some sort of core, either a fiberglass or epoxy core for injection molding or you could brush in a few layers of silicone, some thixo silicone then you could fill the mold with expanding Foam. This will help support the shape. I normally make a fiberglass core, mold that core so i can make multiple copies without having to go through the whole process again and then inject the silicone through the core. Platinum silicone may be inhibited if you use an rtv silicone first.
There are some really nice Tin cure silicones out there for a lot cheaper than Platinum silicones but Platinum silicones last longer.
I used to get lots of RTVC204 off jacobsons and that was great. 16 to 24 cure, great if you havent got degassing equipment.

 

Double post

 

to save making another mould was going to try using the FuseFX jel -e for silicone on silicone
and try slush casting then expanding foam to line and support the head ???

 

Yeah that will work. Is the mother Mold Tin or Platinum because If its Tin it will inhibit the platinum. If its in 2 halfs you can brush both sides for a few layers, bolt them together, Slush a layer or 2 along the seam line and then fill with foam. If possible do a thixo brush layer in both halves and then imbed some cloth like cheese or terry cloth into the silicone. This will help the silicone bond to the Foam and get a really good grip. Other wise the silicone wont stick to it.

 

It is Tin cure... a one piece but cut up the back of the head and a fibreglass 2 piece jacket, using the fusefx product what
silicone could be used, may now have to make another mould from a resin pull from the mould
what product would you suggest to make a mould for silicone.
I also was going to make a wearable mask by working on a resin pull, cupping the eyes to
a lifecast of my face and opening the mouth a bit and cupping the lips all ideas running
away with me but just getting positive feelings from what I have done so far..