As part of the upcoming birthday party for Baby P, we made some crayons shaped like rupees (the gems used for money in the Zelda game series for Nintendo) for the kids to hunt for in the tall grass . . . and maybe inside some conspicuous clay pots.
This required a bit of planning. First came the rupee hunt idea, then the search for a jewel-shaped mold (I was willing to settle for anything vaguely jewel-shaped, and large enough not to be a choking hazard, but not so large as to use thousands of crayons). No luck. I thought about using cookie cutters, but couldn't find one the right shape, and in the end, wasn't sure that a cookie cutter would cut crayon wax well enough to warrant investing in a make-it-yourself cookie cutter kit.
I searched around a bit and finally happened across this silicone mold-making kit. i bought a one-pound box for this project, carved a rupee the desired shape and size from a bar of glycerin soap, then cast it in the silicone compound that my husband mixed up using the kit.
Note: there is a very short cure time on the silicone compound, and several people had posted product reviews mentioning that they couldn't get larger amounts of compound mixed before the cure time ran out, so their molds failed. My husband's trick is to pre-knead each part of the two-part compound separately to get them warm and pliable before kneading the two parts together. It extends cure time and I'm happy to say it worked like a charm.
We ended up with four molds made from one box of compound, and three were useable for casting crayons (the fourth ended up with some unfortunate air bubbles).
We sat down to peel a few hundred recycled (thrift store) and new crayons. Part way through the process, I discovered soaking them in a solution of warm water and dish soap serves the dual purpose of cleaning the recycled crayons and loosening the paper wrappers; give it a try!
The crayons were sorted by color to match rupee colors, then broken to bits and loaded into the cured molds.
With the oven temp set to 230 F, the molds were loaded into the oven atop a wax-papered cookie sheet and cooked for about 20 minutes until nice and melty.
Cooled, popped out, burnished with a spoon, and ready to be discovered by a bunch of little adventure kids. So fun!
The molds held up pretty well through the casting, cooling, and extracting process of close to a hundred crayons (hopefully enough for each kid to take home a full set!). In the end, a couple of molds had small tears at either end, but still held melted wax.
Thanks to this Flickr image, discovered via Pinterest, for the pinspiration!
(p.s. you can make these photos bigger by clicking on them . . . but you probably knew that!)