About the vises - I think I've seen one sold that had rubber grips, but it wasn't worth the extra money (since you can use that extra money to buy yourself some molding compound and make better grips from that). Usually, a vise is not something worth spending a lot of money on, unless you need special features, like being able to tilt your object to a specified angle. Anyway, I use a regular vise padded with scraps of silicone that I have from moldmaking, so I would recommend looking for some scrap rubber, soft if you can find it. However, if the objects you are drilling are flat, hard(er) rubber and many other things should probably work.
Diane - I wanted to add some information to your library
What you say about polyester resin not curing if it's in contact with air is not true, at least not always. I've used 2 different formulations (gel coat and bonding resin from Douglas & Sturgess) and neither one ended up with a tacky surface. If anything, the finish was harder than than Easy Cast (on both the mold side and the air side). The only problem I had, if you want to call it that, is that both of them dissolved my polystyrene mixing cups, which I use with epoxy with no problems. (However, it took maybe 15 minutes to eat through them to holes, and by that time, there was only residue left in the cups and I didn't end up with a gigantic spill. Actually, the way the cups melted looked pretty cool.) And, ofc, polyester is not something I'd recommend for jewelry because the unbelievably horrid and persistent smell and the associated health effects are just not worth the cost savings.
Also, I was wondering, does anyone know what would give the least flexible result for very thin casts (a couple of mm or less)? Obviously, Envirotex Lite should be better than Easy Cast, but any thoughts besides that?
When I saw the thumbnail of this, I had a feeling it's you. I think with just the lower stone, it would've been too traditional, but maybe not if it was attached to the cord in two places, so that it was hanging down a bit? Something to try.
Anyway, I think the covered wire is what made me think of you when I saw it. If you ever find time, do you think you can do a tutorial for how you do it so neatly? Thank you for posting your beautiful work, as always
P.S. When I was little, I used to collect cute and unusual tiny stones that I found playing in the sand and just digging in the ground, for who knows what. Scavenging is fun
Silicone putty is a good option because silicone is the best class of mold-making materials. However, liquid silicone is much better for making molds with multiple cavities. Most liquid silicones need to be vacuumed (which btw is different from vacuum forming), the equipment for which costs hundreds of dollars, but there are a few that do not. Oomoo 30 by Smooth On is one of them, and in general, it's the best "starter" silicone that I know. You won't be able to use it to make molds of highly detailed things with it, but it'll be just fine for the types of things in your pictures.
Things in your pictures are made commercially, and things in the two pictures are made using two different methods. Commercial casting is completely different from casting at home. So... don't even try to figure out how it was done because it will not help you. I'm too lazy to type it out, but, just trust me, it won't. Instead, think about your problem in isolation.
Now, one problem that is probably common is, people attempt to paint their casts as is, the way they come out from the mold, without doing any kind of prep first. This does not work (usually, unless you get lucky) because the casts are still be covered by mold release - which will release the paint from the cast. And, you have to use a release because not doing so shortens the number of casts you'll be able to make with your mold before it breaks down. So, what some people do to avoid having to remove the release is, they spray primer directly into the mold prior to casting. The primer acts as release, and you don't need to remove anything prior to painting.
You can get more details on this technique and find out what paints work by searching taxidermy forums. (I don't care for painting my casts, myself, so this is about it that I remember off-hand.)
Btw, brushing colored resin in some parts of the mold is not much different from layering. However, resin is a bit more viscous than paint, so you won't be able to get a whole lot of detail that way.
I saw a video where she used a whole 2lb kit to make a mold of a pumpkin that she then used to cast a candle, so you might not be wrong. It's just easier to do that than to explain how to make a mold box and how to calculate how much silicone you need...
You can make a mold box using cardboard, boxboard, or foamboard + hot glue, though I read that you can also put it together using silicone caulk, so I want to give it a try since it might be less messy. I use all three, depending on what I have on hand. And, when the mold is ready, you just break up the box and take out the mold with your positive - e.g. bracelet - it's usually stuck to the silicone, and then, carefully take out the positive from the silicone.
You can also use clay to make walls and barriers, like plasticine - just make sure it doesn't contain sulfur, because sulfur inhibits silicone from curing. The good thing about clay is that you'll use it over and over and over and over again. You can use it to make the whole mold box, actually, though I don't think anyone does that. More often, it's used to help make 2-part molds, or skin molds with mother molds, stuff like that. Smooth-on has a lot of really awesome videos on Youtube linked from their site if you want to learn about more complicated molds... I don't have much use for it, but it's pretty neat to see molds of gigantic things, like a fireplace mantle, or a boat
Do you use the whole tube of silicone caulk at once? If not, how do you keep it from going bad? I was thinking of using it uh basically instead of hot glue, but I only use a little at a time, so I wonder if a tube of caulk would last once it's opened...
Also, liquid silicone would not cost you $35 per mold, even if you used the most expensive stuff ($50ish for a 2 lb kit) - as long as you make a tight-fitting mold box since the wall doesn't need to be thicker than 1/4" for a regular smooth bracelet. Cheap stuff that Sherri Haab uses (Oomoo 30) would end up costing you about $5ish, just like the caulk, and it would probably last longer and give better results since the formulation is designed for mold-making... Oomoo 30 really is great if you don't have specialized needs and if you are ok with a 2-year shelf life. Of course, you'd have to buy the 2lb kit, which costs around $25, but it's really hard to stop with just one mold, anyway - so I'm sure you'd have no problem using it up