Question; Plastaline and molding

Vargre

New Member
So i've done a sculpture in plastaline. Sulfur based clay. Didnt do my research, bought Rebound 25. Not compatible. Ok. What is? Only thing i've found is a polysulfide rubber FMC. 500$ for 5 gallons. Little expensive. 100$ a qt. Says its not compatible with resin cast. So, i appear to be ****'d. I cant do a hard mold, obviously. So ultracal is out. Alginate is too soft and tears too easily...I was thinking if i could just get one mold out of the cast then I could do a silicone with the Rebound of that cast. I tried an acrylic sealant. I ran a few test molds and its sketchy at best. I think...im still waiting for the last one to dry and it has more substance than the others. As in, it actually seems to be curing above the plastaline as opposed to just dripping off in a gooey mass. Anyroad, ideas?
 
Tin-cure silicones are generally less sensitive to sulfur and other inhibitors. Give it a good seal with a sealer of your choosing, apply a release, and use a Tin-cure silicone like Mold Max 30.

If you want to try using the Rebound, which I really wouldn't recommend due to its specific sensitivity to sulfur, you could seal the sculpture and try Inhibit X and a whole lot of finger crossing.
 
What Mr Mold Maker said. Thats the only thing I can think of. Where the hell did you even get clay that has sulfur in it? None of the places I go to, or laguna clay distributors even sell the stuff. Its like getting leaded gasoline :lol
 
I actually read that...after the fact. I did SFX back in the '90s and im so outta the loop these days. Just getting back into it. I shouldve done more research. Ill know if my test mold worked out with the sealant in the morning. But im most likely going to go with your suggestion because i dont want to risk the sculpture. Theres over 20 hours into it now and I know even with the sealant working on a test mold, I could **** it up on the main piece through slight mishap. Thanks for the reply and the help, Mr. Mold Maker. Much obliged.

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Plastaline. I love it. I use the Roma Medium and its just a great product. But I did all of my work with rigid molds, using ultracal and running foam or slush. This is my first foray into silicone molds. And yeah, you have to order it.

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One more question? The Mold Max 30, XLS II, and the rest suggest vacuum degassing. Mold Max 14 NV and the Stroke do not. Will those be just as good?
 
I didn't know you could still get sulphur clay. It's all they used back in 70sand 80s so there must be a way. Your work area must stink to high heaven.
 
My pleasure.

Chavant's Monu-Melt is a great sulfur free alternative to Roma for future projects.

You can use whatever silicone you like, just make sure it's a tin cure and you shouldn't have any problems. If you're doing a brush up, degassing really isn't necessary in my experience, as brushing on the silicone will reintroduce the air anyways, but if you'd feel better with Stroke or 14 nv you can absolutely use them.
 
I didn't know you could still get sulphur clay. It's all they used back in 70sand 80s so there must be a way. Your work area must stink to high heaven.

I didn't know you couldn't get it anymore, not that I'd ever want to.

I'm a product of the 70s and 80s and I think my hands still smell from it. The joke in the shop if you were working on a large piece was 'guess I'm not eating a sandwich for about a week'.

Roma, Bob Kelly makeup, vulcanizing Bau foam...there were a lot smells back then.
 
Tin-cure silicones are generally less sensitive to sulfur and other inhibitors. Give it a good seal with a sealer of your choosing, apply a release, and use a Tin-cure silicone like Mold Max 30.

If you want to try using the Rebound, which I really wouldn't recommend due to its specific sensitivity to sulfur, you could seal the sculpture and try Inhibit X and a whole lot of finger crossing.

I agree. While I still have some Roma around I haven't used it for at least 15 years, but I thought tin was okay with it, CX-5, etc.

I love Smooth-On, but they tend to be (understandably) overly cautious with their product descriptions. I use the stuff daily and never had a problem with anything they make. As a matter of fact, I just finished off a gallon kit of 321 that has to be well over 5 years old and sparsely used over those years, not a sealed shelf queen. Never had a platinum sil inhibit cure yet (although everything it contacts is either Aves, Chavant or Kleen Klay), but the the reputation is it's some sort of alchemy.
 
Same here. We used Roma for like, everything. Now that im getting back into it, I just figured id go with what I know. I still love the way it works and havent found anything I like better. I just didnt realize the Platinum silicone wouldnt cure with sulphur base clay. I did get a partial cure using the Rebound and acrylic sealant on a test mold. Partial I would guess because i didnt hit the edges with enough of the sealant. That being said, I still dont want to risk the main sculpture on a guess so I bought Mold Max NV 14 and taking Mr. Mold Makers advice. Planning on doing the mold Friday.
 
17554020_10155011258670729_361116916033186029_n.jpgIll post it...but its the first thing ive sculpted in like 15 years so...take that for what its worth. Still needs some clean up around the horns and teeth but, im casting tomorrow. 17554468_10155011063050729_2925581047279427485_n.jpg17554167_10155011063040729_2301180833696386036_n.jpg17553759_10155011063070729_1289415834157636914_n.jpg
 
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Looks impressive to me!:thumbsup I'm still nowhere near that level of detail and I've been continuously sculpting since...well, forever!
 
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