Mold material

duck · Post by **duck** » Mon Mar 16, 2015 6:35 pm

Has anyone ever used sculpty or similar material to form molds?

The stuff starts out like clay, but is hardened in the oven.

I figured I'd ask before trying it.

Joseph Osborn · Post by **Joseph Osborn** » Mon Mar 16, 2015 8:23 pm

It'll work. Same principle as a rigid fiberglass mold. You have to be careful of your draft angle and you can't have any undercuts. And depending on what you're going to use as your casting material, you'll need a very effective barrier coat/mold release, like PVA.

Joseph C. Brown · Post by **Joseph C. Brown** » Mon Mar 16, 2015 9:13 pm

I've done that with Magicsculpt (pretty much the same stuff as Aves putty). I prefer these two putties to Sculpy because they air-cure over several hours.

I'll see about getting some links up to pics showing what I've done. Modelnutz saw one of these at Wonderfest and in a calm, patient voice explained to me that there were such things as RTV molding rubbers from many vendors these days...

modelnutz · Post by **modelnutz** » Tue Mar 17, 2015 7:14 am

Valdore · Post by **Valdore** » Tue Mar 17, 2015 8:38 am

Tried it. Not the best. You can get Sculpey moldmaker. Less rigid, and more rubbery than the clay type. That will give you the same, if not slightly better results.

Word of caution on Polymer clays. Don't leave this around styrene parts, and forget about it. Sculpey, and other products like it will bond to, and/or destroy detail on regular kit plastic. If not the parts themselves.

Just don't, and don't ask me how I know.

duck · Post by **duck** » Tue Mar 17, 2015 3:24 pm

How about the re-usable molding materials? I picked up some of the Alumilite Amazing remelt. There is also something called Blue Stuff on eBay.
Does this stuff work ok with regular resin?

Thanks!

Stu Pidasso · Post by **Stu Pidasso** » Tue Mar 17, 2015 3:49 pm

duck wrote:How about the re-usable molding materials?
Does this stuff work ok with regular resin?

Thanks!

In a word, no. Unless it's a really, really slow curing resin.

Kylwell · Post by **Kylwell** » Tue Mar 17, 2015 4:25 pm

Because it's thermally sensitive it tends to deforms when use with fast cure resins.

Kekker · Post by **Kekker** » Tue Mar 17, 2015 5:55 pm

I've used Milliput white for a couple of simple open molds. I needed (OK, wanted) a clear headlight lens for a car. It came with chromed ones. I mixed up some of the milliput, covered it with a layer of release and pressed in the part a few times.

When it hardened, I heated up the end of a big clear sprue and mashed it into the mold. A little trimming, some shaping the back to make it lens shaped, and backed it with foil. Worked nicely!

Of course, you couldn't do this with anything too big or deep, but if you have a smallish part you need to duplicate, it works well with softened styrene. It may take a try or two to get the quality of part you need, but you're only using up time and sprue.

Kev