In this case, I decided to try to cast brand new custom tokens in resin, and make enough for my own use in the game. So far, I have not been fully successful, but I have played around enough to share my experiences as a first time resin-caster.
I am basing my design on the fighter tokens that Spartan ships with its modern fleet boxes. The picture below shows a pair of tokens with the fighter elements cut away, leaving only the basic hexagonal shape of the token.
Note that the masters are seated inside an old, plastic blister pack. Not surprisingly, I have a ton of these things lying around, and I accumulate more all the time. My plan was to use it to define the structure for my molds.
The molds are made from a two-part rubber mix. The technical term is "room temperature vulcanizing" rubber, or "RTV". Once the A and B parts are mixed, as shown above, the stuff starts to react and set. In this case, the molds firm up pretty solidly in just a few hours. In the picture of the 'masters' above, the parts are already coated with a thin layer of lubricant to keep them from sticking to the rubber material.
Before pouring the rubber into the mold, I started by using a brush to push a small amount of the mixed rubber material into the corners and details of the parts. I was hoping this step would ensure good detail quality, and it did help, but I can't yet say that it was truly necessary.
With the edges coated, I went ahead and poured the rest of the rubber to fill out the mold. I'm not sure how much material is really necessary, but I tried to aim for at least a half inch or so of spare material to make a reasonable durable shape.
Hooray! A mold is born!
Unfortunately, as you can see, the first version left something to be desired in the details department.
My second pass was much cleaner, and I quickly went on to mix and pour some two-part resin (not: not rubber) to see how a finished part might turn out. The material I happened to have on-hand was a clear resin from a local craft store.
The results were not terrible, but not really up to snuff. To my eye, the finished parts look less crisp than the mold itself, and the material shrank significantly while curing. On the up side, the clear material made it easy to find and remove any bubbles in the curing material. I might try one more pour with this resin, but, if it doesn't turn out better, I might have to go out and try another material. There are any number of casting resins out there for experimentation.
A note to readers: I have been experimenting with these parts purely for my own use, and I am not handing them out to other people. The token design itself belongs to Spartan Games.