But I've still got a few things cooking that I think are worth documenting.
Right now, I'm working on reproducing the belt from Superman Returns. Though not a very popular version of the costume, I am a fan. I am lucky enough to have access to a few made-for-production costume pieces, and I got my hands on a belt recently. I only had it for a very short time, so I needed to mold it quickly. The paint job on the belt was also VERY frail, and was cracking all over the place. For that reason, I decided to mold it using silicone putty, instead of the traditional "pourable" stuff. I figured this would not only kick much faster (it cures in an hour) but would also eliminate some of the problems I would have encountered using regular liquid RTV. Namely, I didn't want to do any further damage to the paint job, and I was unsure how it would react with the fabric elements embedded in the belt underneath, should it accidentally seep under.
Fortunately, I had a stash of the stuff sitting around, so I didn't have to order any. It worked really well.
I ended up taking two molds of the belt. One of the buckle, just as a test mold, and one of the entire belt. As luck/unluck would have it, the smaller mold of the buckle captured a bit more detail than the larger mold. I guess the work time with the putty is pretty short, and it had started to kick by the time I got to the buckle on the large mold.
Here's the large mold of the entire belt. Oh, and don't even get me started on the trouble I had to go through to get the belt to lay flat for molding. TOTAL pain in the rear. But it all panned out.
Here's the smaller mold of the buckle.
The overall plan is this: mold the belt, pour up a new master, clean it up, then re-mold using regular RTV, then cast one up in urethene. I'm doing this because of all the damage that was done to the original paint job, which was subsequently captured in the mold. So I've got to clean it up.
The first step is casting up a positive from the mold, which I can then clean up using putty and sand paper. The challenge now is working with my putty molds. Because it's not a straight-up liquid, it will not sit perfectly flat when placed on its back. Cuz you know, it's all lumpy and whatnot. So I've decided to make rigid jackets for the molds. That way, when I go to pour up the rigid positive for remastering, it will be as flat as the original.
To make the jackets, and the positives, I'm using a product by BJB called TC-1630. I've probably written about it before on this blog, as my managloare rifle is cast from it. 1630 has some really interesting properties that make it a good choice for this project. First and foremost, it has almost ZERO shrinkage upon curing. It's completely undetectable. So it's also a good choice for a gel-coat application, or something like that. That's also the main reason I'm using it to pour my positive master. Zero shrinkage, and it's also really easy to work with. Sands really nice, and putty/paint take to it very well. The downside is that it's not terribly strong. So you wouldn't cast like a solid resin blaster or something with it, as it would probably break if you dropped it. There are better resins available for casting positives as far as strenght goes. But since my main concern is size, I've decided to go with it.
I still had my mixing drill bits from my mangalore rifle project, and put them to good use here. They made short work of mixing up the different halves of the 1630. You do NOT want to try to mix this stuff by hand. It's like a gooey liquid on top, and hard packed sand on the bottom. Takes about 10 to 15 minutes WITH the drill bit. I cannot imagine how long it would take without.
I figured I would start with the smaller mold, just to prove out my concept. And because it's easier to work with. I started by laying aluminum foil down over a piece of plexiglass. I wanted a very flat base, and I needed the jacket to be removable. Didn't want it sticking to the plex.
I mixed up a red cup of 1630, and got to work. The stuff kicks pretty fast. It has about five minutes of work time, and then it just turns into increasing degrees of thicker maple syrup. You can push it around with a brush for like 15 minutes, but after five minutes, it's too thick to do anything useful with it. After that, it's 24 hours before full cure.
I start with a wet coat directly on the mold. Because the stuff is at its most fluid at this point, I want to make sure all the nooks and crannies are wet with it. I don't want the mold buckling under the weight of itself during final pour up.
With the mold nice and wet, I start laying in fiber. You know, the stuff for fiberglass? This makes the 1630 much stronger. It's amazing stuff. I pull the fibers apart a bit, to loosen them up, then place it over the wet 1630. Then, using a chip brush, I glorp 1630 over the top of it, tapping down on it gently to work it through the fibers.
I worked from left to right, then did another round from right to left. Probably overkill, but I didn't want to waste any 1630.
So here you have it. Jacket is all set, and is curing.
I'll do the larger mold next, but probably won't document it, since the process will be the same.
Next up, I'll pour the master.
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