What kind of silicone is everyone using?

[inblackandlace]

I ordered a pound of EasyMold Silicone Rubber for the war axe I'm working on and let me tell you, I VASTLY underestimated how heavy silicone is. I paid about $40 with shipping and ended up having to order a whole nother pound of it so I could finish my mold. I want to cast much more than just this, but I'm a bit overwhelmed by how much it all costs. What is the most cost effective silicone? I've tried the caulking method and I can't get it to work. I plan on trying again, but I want to make decent sized molds as well. I'm very new to mold making (this is my first one), so I don't have enough experience to be picky about hardness.
Any help would be really greatly appreciated!

 

[robstyle]

regardless of the supplier, its sold by weight, you are back in the same cost area due to shipping. I use MPK for most materials as he is a direct supplier not a reseller nor does he sell items at full mark up he secures at a discount (shelf life expiration date or contaminated material). He supplies the big guys but caters to the hobbyist as well. His overhead is low with top notch product. For the price you are getting professional grade material at the same prices of the lower grade hobbyist prices.
Mold Making Silicone, moldmaking silicone molds resins hobby moldmaking

 

[Luke0312]

Lately I've been using smooth-on mold max. A gallon, which is right around 10lbs is about $90 (price varies a few bucks depending on hardness and properties) plus 16 or 17 for shipping. If you find something cheaper, it won't be by much, but I haven't seen cheaper.

Don't bother with the caulk unless you're just making a temporary mold of a basic shape item and plan to remold that or you really enjoy finishing casts.

 

[Kubla Kraus]

I don't know what your mold box looks like, (I guess an axe box will be big no matter what you do) but most of my molds have been pretty close to the shape of the thing I was making, so not that much silicone was needed. A 1" border may be all you need. The box doesn't have to be a rectangle, cutting it closer to the model within reason may save you buying more silicone. Foamcore and hotglue are relatively cheap

 

[inblackandlace]

I was only casting the blade for my axe and I still ran out
I'm not sure if this mold is going to turn out or not. There seem to be a lot of bubbles around the blade. I should be getting the rest of the silicone today, so I'll know by tomorrow if it's a usable mold or not. Fingers crossed!

 

[Kubla Kraus]

bubbles in the mold may not be that big of a problem because the resulting reverse bubbles in the molded part can be sanded off. it just means more finishing work. rememeber to pour the silicone in a as narrow a stream as you can from a height, like a pencil lead wide or smaller from a foot above. This will force bigger air bubbles to escape. If the mold looks too bad, just cut away the affected area and repour. The new silicone will adhere to the cured parts. Use the part you cut away as filler in the second pour. Another thread suggested using a sander to help vibrate the bubbles out of the silicone.


Make a note of the volume of silicone you get for your next pound. That will give you a pound / volume converion factor. Then next time, you can fill your mold with water or rice or something then dump that out into a measuring cup to get the volume you need, then multiply by your conversion factor to get the weight of silicone you will need to order. Or just order it by volume if its listed that way.