Joshmohr:
I need a hand on this… i just made a few molds out of silicon; is this a wise idea? I’m thinking of making my own troops, using a bit of Wax… Please respond.
-it dries in 5 hours, so in 2 hours ill put the figure in the mold, and lace it with a Oil Lube.
GRNDL:
Do you mean mean silicone rubber, or silicone caulking? Or some other form of silicone? Or do you really mean silicon, the sand like substance?
I once used silicone caulking as a casting material and it sort of worked, but it was for prosthetic make up and burned my skin when I wore it, but THAT is another story…
Joshmohr:
Thanks, GRNDL! Im using Silicone Caulk. What procces did you use?
GRNDL:
Well, as I said, I was using it the reverse way to how you want to use it - to cast with, rather than to make a mould out of it. My mould was made of hydrocal plaster. I first used rubber cement as the basis of the cast and when that ran out, filled the rest of the mould with silicone caulking.
I don’t see why it wouldn’t work to make moulds, but you should be aware that thick amounts of the caulking takes a long time to cure and dry out completely. It might be dry to the touch in an hour or so, but it will take days to fully cure. This might not affect your mould that much, but chemicals will continue to evaporate from the caulking for a long time. It was these chemicals that burned my skin when I wore the prosthetic I made. I still have the prosthetic though, and the silicone itself is still ok - seventeen years later. 
For the record, the caulking in my prosthetic was at most 1/2" thick and it was a Klingon forehead piece - from a dark time where my Trek fandom spirit surpassed my rational thinking. I almost joined the IKBF in Niagara Falls. Thankfully, I have since recovered and instead focus my time on becoming a viking/dwarf/chaos dwarf instead.
I’m not sure how those chemicals might affect the wax, if they do at all. You’ll want to do it in a well ventillated area for sure. If you can smell the acrid vinegar-like smell of the caulk, loosen some windows.
I would suggest, in the long run, using silicon RTV rubber, rather than caulking. Its a lot more flexible, safer and easier to use, IMO.
Kera foehunter:
so this explains why you so caulky grndl???
i also heard of this method of using caulk
but i always was a afraid my figure would be like hans solo
frozen in cabonite forever
let us know how it turn out josh
Baggronor:
If you’re gonna cast, you may as well cast in metal, its really not as hard as you’d think.
For help:
http://www.myheap.com/book/appendix-d/castingfaq/castingfaq.php
http://www.tiranti.co.uk/subdivision_product_list.asp?Content=Hand+Casting+Starter+Kit+-+White+Metal+%2F+Tin+Alloys+-+Casting&Subcategory=63&Subdivision=241
Willmark:
Also for Josh’s benefit make sure you confine the the discussion to the making of molds to your own models not that of Games Workshop or another miniature manufacturer.
Consider this a Public Service announcement. 
GRNDL:
After thinking about it for quite some time, I’m under the impression that silicon caulking would probably stick to your master model. You’ll need some sort of release agent to act as a barrier between the caulking and the model and I have no idea what would do it. You might want to do some experiments on disposable models/items before using it on the model you want. Vaseline might work, but I’m not sure what sort of chemical reaction you might get between the caulking and the agent.
Joshmohr:
I use cooking oil to as a Lube
Kera foehunter:
well i have to see this !! could you post this silcone mold