At the Houston Maker Faire, I had the pleasure of meeting Jared from Fine Clonier who owns a dental vacuum former! He would carve or cast the object he wanted to make a mold out of, in this case JarJar Binks in carbonite and then vacuum form a mold over the object.
He used a porus material to carve his form from so it could release from the plastic, heated up the plastic with the vacuum-former and the vacuum sucked the plastic over the form. When he knocked out the form, he was left with a mold!
Here’s a link to his vacuum forming video: https://www.youtube.com/watch?v=hYvISnb5rws&feature=youtube_gdata_player
I happened to have a booth across from his, so he sent someone over to see if the mold could be used for soap. The answer was YES! We poured soap into the mold he had just made and viola! Here is the result:
Then Jared came over and made one in green!
…and after he learned that you can cast soap in these molds, he started making molds and his wife poured soap into them! Check out his flickr stream to see what they came up with!
You can find a dental Vacuum-former on ebay for around $400. I think you need an air-compressor to use it as well.
If your city has a TechShop, I think most of them have Vacuum-formers. They are fairly easy to use (you set a sheet of plastic down, the heater heats the plastic and you press a button to start the vacuum, and press another button to release your form.) I’m a member of the TechShop Austin-Round Rock location and we have one! They give tours every day and are open from 9am – Midnight if you want to check them out. They also have lasers, a Maker Bot 3D printer (the Replicator 2), a vinyl cutter & many other fun toys.
Are you making your own soap molds? Do you have tips to add? Happy Making y’all!