When John called us at UArts and asked us what kinds of smooth-on products we’d be interested in trying out, I had no idea what to ask for. Since we are a glass program, I was particularly interested in some of the unusual materials that were clear, translucent, or in other ways similar to glass.
I decided to schedule the mold-making and casting unit of our classes to coincide with our visiting artist, Matt Eskuche. His work is very much about copies and making one material look like another so it seemed to fit. Here’s an example of his work. All hand-blown glass. He’s good.
hand made glass trash objects, made by Matt Eskuche.
Matt showed up and we asked him to demonstrate making one of his “beer” bottles on the torch.
Matt getting started
...and just about finished
Matt and I thought it would be cool to make one glass object, and then reproduce it in several glass-like materials.
I wanted to demonstrate a 2-part brush-up mold to the class, so we used Matt’s Bottle and the material Smooth-On sent us to do it. I made one major mistake, and didn’t add the thickening agent in the first demo I did. I couldn’t understand why the brush-up rubber was behaving like a pourable rubber. I corrected the problem later…
separating the two-part bottle mold
The material I was the most excited to try (and the students were similarly enthusiastic) was the SMASH! plastic. It’s what special effects people use to make panes of glass to get thrown through and beer bottles to break in barroom brawls. We decided to do the latter and I volunteered to be the guy who got a bottle broken over his head. We expected a bit of necessary experimentation before getting a successful result and were correct. We were doing a rotational casting, and the wall thickness is supposed to be about 1/8″ around. We just guessed on the first casting and used WAY too little material.
First bottle attempt
I also de-molded a bit on the early side and the bottle collapsed into a semi-rigid puddle. It was actually pretty interesting, similar to what glass does when it is slumped or dropped into the furnace. Not what we were going for though.
We set up the mold again. This one was small enough to hold together with a big rubber band. I used the same sulfer-free clay we had to produce the mold in the first place to plug up the opening so that we could rotate the mold into every position. After the first attempt, it was easy to see how many times thicker the wall needed to be so we multiplied our mixture by that number. We rotated the casting by hand, taking turns and doing it consistently for 15 minutes – more than the directions specified. We also waited an extra half hour to de-mold. This attempt was much more successful although the uneven wall thickness and slight indentation on one side suggest that we should have continued moving the mold around for at least another five minutes.
First "successful" special-effects bottle
I think for the next we do this unit, I might design a quick and dirty DIY automatic rotational casting machine so I can just drop the mold in and leave it for the duration of the curing process. Still, it was a pretty exciting thing for the group and quite similar-looking to the original.
The only thing to do now was smash it over my head.
This is not something totally foreign to me as you can seen here.
The next thing we wanted to try was to cast a bottle in crystal clear silicone. We liked the idea of one bottle that smashes, and another that stretches and bounces. We also wanted to try the semi-rigid white plastic so we decided to try them out on some smaller things first. One student had some small, simple rubber molds of little action figures that she volunteered.
rubber molds made by pouring around objects in plastic cups
The crystal clear Silicone is, as far as I know, one of the only Smooth-on products that is not 50/50 by volume. It is 100:150 by weight. The stuff is a little too toxic to let students use on their own anyway, but it was a good experience for some to learn to use the tripple beam balance. The silicone was excellent for these small, narrow molds. It flowed very well and had enough working time to get everything full before it started to cure. We left these objects overnight under the vent-hood just to be safe and de-molded in about 48 hours.
Most of the castings were missing the ends of their swords or a narrow extremity or two, but all-in-all, they came out really well.
The white plastic was next. This one was exciting because of the instant gratification factor. They only have to cure for 15 minutes before being removed from the mold!
White plastic ninja in rubber mold
In fact, this stuff cures so fast, that we could really only mix enough for two ninjas at a time. The first batch we mixed up we ended up wasting a lot because it just set up so fast. After doing rotational casting with the SMASH! plastic, we thought that this stuff might work in that way as well. We had wanted to make a hollow plastic bottle (that looks like Matt’s “White Trash” series above) so this is something that I will try (although we ran out of time during his visit).
We also wanted to make a clear silicone rubber bottle, but didn’t realize that we couldn’t make it hollow as easily as the more rigid stuff. We’ll have to make a slightly more sophisticated mold to cast the silicone as a hollow form. I think we’ll make a hollow wax that is the correct thickness, make a poured rubber mold around that, remove the wax and then cast it in the clear silicone.
The only material that was not sampled was the body-double which I have used before and like. I was surprised, since I offered it up to anyone interested. I thought it might be less intimidating than some of the other processes since it can be put directly on the body, but students were really getting into the materials demonstrated. One student used the two-part rubber mold to make waxes of baby-doll parts which were then made into two-part plaster molds. We blew glass into them for the student to produce some sculptural parts.
Some waxes produced from 2-part brush-up molds and the resulting glass objects
I’m still working on collecting more documentation and will add to this blog as we produce more with all of the products that Smooth-On so generously provided. We at UArts are thankful to them and for John Shea for organizing this whole thing and spreading the love and knowledge about casting and mold-making.
