Tag Archives | rubber masters

Off with her head! (again)

I never imagined, when I began molding horses here at the pottery, that I’d be decapitating so many of my ponies. I had hopes early on that Elsie would cast bob-tailed but otherwise whole, but there was just too much of a turn so off went the head.

The one I’m holding in the picture isn’t the real Elsie master head; since I had a poor casting I had the luxury of making a test cut. I wanted to see how it would set in the rest of the mold and how I would create the two separate molds – one for the head and one for the body – from the pieces. I think this extra needs to go live with my friend Jackie Arns, to keep the infamous Beowulf company. Jackie won’t mind that Emma, the ever-shedding studio dog, left a little bit of herself in the rubber.

Continue Reading

Indoor camping

That’s what the Kathman family has been doing since yesterday, after we traded our electricity for five inches of snow. As you can see from the picture, my oldest son Brandon totally approves!

I can almost forgive him his enthusiasm; after all these years in Scouting, he’s at least really handy with a camp stove.

I’m not sure this guy would agree. It’s probably not visible in the picture, but the poor little fellow had icicles hanging from his tail feathers! And I can attest that the only thing more useless than an electric kiln during a power outage is an airbrush. My plan to return to glazing today was thwarted.

But I did promise to post how this was fixed.

Here are three of my legless Vixens. I have quite a collection of them now. Sarah suggested that I turn them into ornaments and hang them from my Christmas tree. I might have to add a small tree to the studio next holiday, just to do it. If course it’s a lot easier to laugh at the idea of a tree festooned with mangled Vixens now that I have one with four legs!

My final solution was to open the mold, cement the hind gussett in place (thank goodness for good mold keys), and then pour the lifted leg first. Once the leg was filled and had set up enough that it would not spill out again, I closed the mold and poured the rest of the horse in the normal way.

This worked just fine, though if I had it to do again I’d cut a sprue level with the leg pour. That’s because once the mold refills, air gets trapped where the first and second pour meet. A sprue would allow that to vent. It was deep in the hindquarter, though, so it was really just cosmetic. The bubbles did give me a chance to test out my new 16 gauge hypodermics, though, and they worked beautifully. I’m still skeptical about being able to insert rubber through the mold walls, but I suspect I’ll get opportunities in the future to test it.

I also think there is a better tool for pouring into the open leg. I used a disposable plastic spoon, but that method lacks pressure. Pressure is part of what drives the viscuous rubber down the thin legs, and I think that had I not been using really fresh rubber I would have still encountered problems. Next time I’m going to try this angled syringe that my friend Elaine Lindelef suggested. That will let me pour the rubber with a little more force, and better avoid getting excess rubber on the rest of the mold.

So with a four-legged Vixen, I went ahead and cut my inside pieces apart so I could pour a plaster test mold. I’m not real confident that Vixen will cast as one piece, but there was one design that might work so I have to give it a try. If it does work, it will save me hours of assembly work.

If it doesn’t, I’m afraid I’ll have no choice but to lop her head off!

Continue Reading