So I do love tiny pottery, but I’m also trying to make some functional stuff.
The latest is Expresso cups. It’s been a couple of months of development so far; here’s what I’m doing:
- Make/get a 3d model
- Print it
- Make plaster molds of the prints
- Make slip
- Slip cast cups. Dry them.
- Fire them
- Glaze fire them.
Phew. So I made the 3dprint the maximum size I could fire: 40mm tall. Looking good.
Then I realised that clay shrinks as it dries. So The cups are small. This clay: 15% smaller – too small to hold a shot of coffee (according to the machine at work!)
Back to the start. I made the master 15% bigger and made a new mold. While it was drying, I decided I wanted terracotta clay for my raku copper clay, so ordered some
Great. This all took a week. Next go, cast and dried, but they are too big for the kiln. This bloody clay has a shrinkage of only 5%!! So I file down the cups and fire them. Great, some copper glaze (3 firings) and some blue crystal (only 2 firings)
I love them.
Took them to the office to show off.. Comments? Needs a saucer!
So to the point.
I started to make a 3D-printed master to make slip-cast molds from, but its really thin and would need a 2 part mold: lots of effort.
So I decided to press mold them. 3d printed master for the negative space inside a saucer. Didn’t know if it would work, but it’s looking good so far. I started out with a hexagonal shape, but seeing it, I hated it and STARTED OVER again!
I have a bunch of them drying at the moment. Will update later.