Release Ultracal

Predasaurus

New Member
Alright, so I tried to mold my sculpture out of ultracal. That ended in disaster, because I applied at least two to three coats of krylon crystal clear, but the mold still binded to the sculpture. The mold and sculpt are now ruined, so I have to start at square one again. Any tips on releasing the mold, so I don't make the same mistake again?

Eli
 
Not sure. I used Krylon crystal clear on mine before and it worked. Took a while though. Ill ask around and see what I can find bro.
 
Thanks kammo. Yeah, I used like three coats, I'm suprised it didn't work. Could the fact that it is water based clay have a different effect on it? I used WED clay for it.

Eli
 
were you expecting the WED sculpture to survive the ultracal mold? It wont ..i dont care how much crystal clear you spray on it. As for the mold? did you vasaline between your first half and removal of clay dividing wall. you need to have some sort of barrier between the two stone halves ( not Crystal clear ..that only seals your sculpture) petroleum jelly is what most everybody uses. If you think its a disaster because there is clay in your mold ..ha ..now for the fun part ..get a wood Popsicle and start cleaning it out ..the good news its in WED ..you could just high pressure water hose it out
 
So much fun! I have seen programs that actually make molds from 3d printers... But you miss out on so much fun. Molding is a true art...and so few do it well
 
Yeah, well I was doing it one half at a time. And besides, the problem was the mold would not come off. I don't know if I used the wrong acrylic crystal clear, but no matter how hard we pulled or how much we chiseled, it wouldn't come off. But would petroleum jelly/Vaseline work as a release agent? Or is crystal clear the only one for releasing the clay and mold?


Eli
 
i dont think you are reading what i wrote. Krystal clear goes on the sculpture. Vasaline goes one one half of the dividing wall ..in other words  first side of stone sets up ..remove clay wall ...brush vasaline on hard stone  ( there should be registration keys as part of that first clay wall build) lay in some pry points with clay on that stone half ..then start building the second half of the mold
 
Ok. That makes sense. But my question is can you use Vaseline instead of crystal clear? I know what you're saying, though.


Eli
 
just the wall. no dont replace it. Again ..with a stone mold, and wed clay the sculpture will not be saved, if thats what you are intending.
 
you should post some pics of your delema ptgreek is right . it will not survive the demolding process the stone is solid and the clay is not. vasaline will just make a hot mess and distort your sculpt, but if you want the ultra cal to come out of the mold easier without so much clay being dug out i have sprayed clear krylon on the mold and used a light dusting of baby powder on the mold . the ultra cal will stick to the powder and not to the clearcoat. Now that does not guarantee the sculpt will survive either ( IT WON"T) but it is a hell of alot easier to get that clay out . try a small piece and good luck.
 
I can't post any pics of the ruined one now, because I restarted the sculpture and I am trying it again. I think the problems were that the ultracal and burlap was not thick enough, so it crumbled, and the other problem is that I didn't put Vaseline on the wall. Speaking of which I think I'll post that today.


Eli
 
Ok i see now. If you look at some of my last posts i have several pics of the ultra cal process. this is how i do it . you start with a beauty coat that you brush on the sculpt and then another much thicker coat of ultra cal and then the burlap with about the same amout of ultra cal in it that way your burlap doesn't seep down to the scuplt and distort anything and then another 2 coats uf ultra cal . I try to get the ultra cal at least 2 1/2 to 3 inches thick that way you are able to pry on it to seperate the mold but if i were you i would go no lower than 3 inchs if you have alot of undercuts. the the vasaline should be used after it has dried and you ahve cleaned the edges nice and smooth and remember to put keys in the mold wall. this will ensure a clean edge and a nice fit . i will send you some pics to you to see the whole process
 
Ok thanks. And by the way, i have now molded both halves, but i ran out of ultracal so the front is thicker then the back. Im not sure if it will be a big problem, but if it breaks I will have to just glue it ultracal


Eli
 
ok good deal . wait you just did the casting ? your on to the next and that is pulling a piece from the mold correct ?
 
Back
Top