Suggestions on making small (synthetic?) Go stones?

I'm looking into making myself a Go set. It's a very old Asian board game. There are a couple instructables on making a board itself, which is pretty straightforward. My problem is in the manufacture of the stones. Basically the stones are flattened out marbles in either black or white. The idea is a bi-convex round stone, usually between 5 and 9.2mm thick, around the size of an average thumbnail. Traditionally these are made out of agate, slate or something similar. My goal is to produce stones that are hard and rather heavy, to mimic the actual stone feel as much as possible. I'm going to need 361 stones for a set, and I want to make several sets (maybe half a dozen). My current best bet is to press clay stones with a mold, fire them without a glaze to avoid non-uniform surface due to contact points, then spray an acrylic coat for color and texture. I was hoping someone might have other suggestions. I was considering an epoxy/resin option that I could press in a mold, then dry into a hardened, dense synthetic stone. But I know very little about epoxies and my options in this. I've considered glass and machined metal, but I lack the facilities and skills. Stone is beautiful but I don't know where to start with detail grinding and mass production at the same time. Wood would be great, but I would have to find/make the world's smallest lathe and I think the man hours needed would be impractical due to the quantities. I'm limited in tools, resources and knowledge on the subjects at hand. I like the idea of making a mold with which I could press several stones at once. Cheap is good and the ability to do this without a kiln would be great. The clay seems my best option but my kiln access is limited, so firing upwards of a thousand stones would be difficult. So if you have experience with a synthetic that I could pour and harden, I would greatly appreciate it.

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Goodhart7 years ago
If you can make the forms,  there are a lot of "automobile body putty" types out there, and other forms of "repair" materials that would make for a varied choice of pieces.
There are little glass half-marbles that are most commonly used in vases, but would be perfect for this. I've seen them clear and coloured, transparent and opaque. They aren't perfect, but they are durable and relatively heavy for the size.

Otherwise, liquid resin would work for you, but it would be much lighter. You just have to pour it into a mold and bake in a regular oven. A quick Google search for 'how to make resin jewelry' will give you a good start.
caitlinsdad8 years ago
Try to find a hard coated candy or mint. Dip it in several coats of clear polyurethane. Just make sure no one tries to eat it. Using plaster to cast a stone might work. It may need a protective coating also. Maybe a hardening clay that you bake in the oven or the new air-hardening stuff. If doing the concrete, just get sand mix concrete or the one with the latex flex additive without the larger stone aggregate mixed in. Concrete shrinking and cracking might be a problem with such a small form.
110100101108 years ago
cast concrete you can add colors to the concrete mix to make shades