Question Regarding Ultracal Mold Making

[NSStudios]

Hey guys! How is everyone? I just recently made an Ultracal30 mold for my Halloween 4 mask that I sculpted, but I’m running into a few errors. My main priority is that after every pull there seem to be a crap ton more bubbles present. I’m aware that it’s likely to have bubbles and cavities form after the more pulls you do, but after the 4th or 5th one just doesn’t seem right. Am I doing something wrong, or is it really that normal? Thank you! Excited to see the replies here .

 

[Mr Mold Maker]

You definitely shouldn’t be seeing heavy breakdown of the mold that quickly.
It sounds like your initial detail coat was probably not mixed correctly. The actual ratio for ultracal as specified by the manufacturer is 100 parts stone to 32 parts water. Often we eyeball it by sifting the stone into water until the water can’t absorb any more, you’ll get a “dry lakebed” effect. Once mixed it should be smooth and the consistency of a milkshake. Any thinner than that and you don’t have enough stone in the mix.. you’ll end up with a much weaker surface.

Next time keep an eye on how much stone is added to the mix, make sure it has the right consistency. If detail is a worry, you can mix in some Die Keen Green (One scoop DK to every two scoops UC) and you’ll get a surface even more resistant to breaking down.

As for the mold you have, giving the pulls a good rub down with Naptha and a rag should be enough to swell the warts and polish them right off.

 

[NSStudios]

You definitely shouldn’t be seeing heavy breakdown of the mold that quickly.
It sounds like your initial detail coat was probably not mixed correctly. The actual ratio for ultracal as specified by the manufacturer is 100 parts stone to 32 parts water. Often we eyeball it by sifting the stone into water until the water can’t absorb any more, you’ll get a “dry lakebed” effect. Once mixed it should be smooth and the consistency of a milkshake. Any thinner than that and you don’t have enough stone in the mix.. you’ll end up with a much weaker surface.

Next time keep an eye on how much stone is added to the mix, make sure it has the right consistency. If detail is a worry, you can mix in some Die Keen Green (One scoop DK to every two scoops UC) and you’ll get a surface even more resistant to breaking down.

As for the mold you have, giving the pulls a good rub down with Naptha and a rag should be enough to swell the warts and polish them right off.

That’s what I thought. And that’s exactly how I made the mold. With the dry lakebed effect to eyeball it. With adding that Die Keen green, is that dental stone? I wasn’t sure if cutting it with that would work wonders or not. I’m about ready to send my master off to get a mold made professionally. This **** is stressful! Lol.

 

[Mr Mold Maker]

That’s what I thought. And that’s exactly how I made the mold. With the dry lakebed effect to eyeball it. With adding that Die Keen green, is that dental stone? I wasn’t sure if cutting it with that would work wonders or not. I’m about ready to send my master off to get a mold made professionally. This **** is stressful! Lol.

Sorry for the delay.. I wrote a reply last night but I guess I forgot to send it.

Yep, Die Keen Green is indeed a dental stone. It will help improve the strength of the detail coat but you still have to mix and apply carefully.

I like to sift all the way around the bowl, just spinning it and filling it evenly from the outer edges in. If you have a lakebed in the center but pockets around the outside, your mix will still be too thin. I apply with a chip brush scooping up stone and almost slapping or splashing it into the detail.. make sure you don’t wait too long between layers. As soon as your detail coat has matted over, you’re good to apply the next. Die Keen is only needed in your detail coat, the rest can be straight ultracal.

 

[NSStudios]

Sorry for the delay.. I wrote a reply last night but I guess I forgot to send it.

Yep, Die Keen Green is indeed a dental stone. It will help improve the strength of the detail coat but you still have to mix and apply carefully.

I like to sift all the way around the bowl, just spinning it and filling it evenly from the outer edges in. If you have a lakebed in the center but pockets around the outside, your mix will still be too thin. I apply with a chip brush scooping up stone and almost slapping or splashing it into the detail.. make sure you don’t wait too long between layers. As soon as your detail coat has matted over, you’re good to apply the next. Die Keen is only needed in your detail coat, the rest can be straight ultracal.

No problem! I do that all the time with texts and posts lol. So then I’d do 2 scoops of Ultracal (sprinkling around the water, evenly) then 1 scoop dental stone, then repeat until lakebed? Or would you recommend whipping up separate batches in different containers (for instance, three different containers each having two scoops Ultracal in one scoop dental stone, mixing that thoroughly) then sifting each one of those containers and until I get to “lake bad”? Sorry to break it down so technically, I just wanted to turn out the best it can be!

 

[Mr Mold Maker]

No problem! I do that all the time with texts and posts lol. So then I’d do 2 scoops of Ultracal (sprinkling around the water, evenly) then 1 scoop dental stone, then repeat until lakebed?

Yep. Everything in one bowl.