Last night before I went to bed, I decided I needed to run another experiment in casting tracks in the snow. I had a bucket of joint compound in the trunk, so I went and got it. I cut up a plastic milk jug to make a casting form. I ran a little cold water in yet another cut-up milk jug, and added a couple of cups of snow to it. I stirred the water until most of the snow had melted and the water was good an cold. Then I scooped out the remaining snow and stirred in some joint compound.

Then I went out to visit my mouse tracks. It was snowing, and from the looks of it, it had been for 10 or 15 minutes. Big fluffy flakes too. I figured that couldn’t be good for the tracks I had found earlier in the evening, but since I already had the compound mixed, I decided to make a go of it anyhow.

I went out and placed my ring around a pair of tracks. I wanted to cast two tracks with the tail marks between them. Then I started pouring in the joint compound. Instead of pouring it into the tracks though, I poured it next to them and let it overflow and fill the tracks gently. That was a good thing too, because when I retrieved the cast, I could clearly see where the stream had poured in (from a height of only about an inch too).

I went back out and checked it after an hour, but it was still mushy. So I let it set all night. This morning as we were getting in the car, I dashed around back and grabbed my cast. It was nice and somewhat solid by then, so I put it in my car and we drove away for work/school.

I found that it was still a little soft, so I quit brushing snow off, opting to allow it to melt off in the garage at work. When I got off work, I checked it out, and I must say… it looks pretty OK!

It’s not nearly as good as a cast made in mud, but it’s certainly identifiable. Some of the detail has flaked off, and the compound is still curing, but I think it’s going to set up all right. I’d post a picture, but I haven’t taken one yet. Maybe later.

When I bought the joint compound, I had asked the store guy where I could find plaster of Paris, and he pointed to the joint compound. “Whatever,” I thought. That’ll probably work. Now what I want to know is – what’s the difference? They are NOT the same thing. Plaster generates heat when it sets, but I don’t know if the joint compound does, and if it does… how much?

I need to go get some plaster and run some more experiments. My theory is that joint compound either doesn’t heat up, or it doesn’t heat up as much. I also think that when it sets, it is merely drying out. Plaster OTOH, is undergoing a chemical reaction and will set under water (remember my underwater heron cast from this summer?)

So… we’ll see.

I started making another Roman soldier costume for Camp In tonight. I actually made a pretty good dent in it. I think another hour or so and it’ll be done. Camp In is coming up fast, so I need this kind of progress! I’m tempted to try making the soldier’s armor too, but that looks pretty complicated. I’ll try to get some of the villager costumes out of the way first, and then if there’s still time, tackle the armor. Again – we’ll see.

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