Welcome to the forum!
I have a big interest in trying to make my own custom chips for the occasional home game..
I have a few questions..
Is polymer clay or air dry clay better ?
Is it possible to get chip molds in Australia ?
Around here when we talk about making custom chips, we're usually talking about making a custom
design with custom
artwork and having that design produced by a professional chip manufacturer. For clay chips, the design gets printed onto an inlay (the round part in the middle of the chip with the graphics) and then the inlay is pressed into the chip when the chip is molded. For ceramic chips, the chip is already molded, and then the design gets printed onto the entire surface of the chip.
Molding your own chips from scratch is a whole different enterprise, and none of us are yet entirely certain how to go about doing it. A few people have tried. The Hobbyphilic video above is one approach, but doesn't come close to the way real chips are made. Here's a couple attempts that are a little closer:
Regarding polymer clay vs. air dry clay - The chips we call "clay" aren't actually made out of clay, and using either air dry clay or polymer clay is not going to get you anything that closely resembles the types of chips used in casinos.
It's not possible to buy chip molds off the shelf anywhere. Chip molds are custom manufactured; they're made by machining high-strength steel. They're industrial equipment and are very expensive. The chip manufacturers have the molds made at high cost, then use them to produce hundreds of thousands of chips in order to pay back the initial investment.
Here's some posts that can help you learn about the different types of chips and how they're manufactured:
Part One
Part Two
Part Three
If you want to mold your own chips, you can certainly give it a shot! Like I mentioned, a few other folks are trying this as well. But if you do, you'll be breaking new ground and will have to do a lot of trial and error to figure out how to make it work. Let us know how it goes!