Here's the Oyumaru write up that was supposed to be here two weeks ago ^^;;
Oyumaru is a cheap, reusable molding material from Japan. (Now that Ai Li's said it, the sticks remind me of agar-agar and I wanna chew on them...) I bought a 7 stick pack for USD3.50 from ebay seller hinodewashi. Each stick is roughly 1.5cm wide and 6cm long.
I decided to start out using the orange stick because I don't like orange and thus wouldn't feel as bad about using one of those cute, chewy looking sticks :p. The Oyumaru feels a bit rubbery and is somewhat flexible.
I wanted to make a cupcake mold, so I used the end of this pen.
To become pliable, the Oyumaru needs to be placed in boiling water, so into the pot! It's recommended in the instructions that it sits in a temperature of 80 degrees celsius for 3 mins.The material went soft fairly quickly and I pulled it out with a pair of skewers.
As you can see, it's really soft and malleable in this picture. The material itself is not at all hot out of the boiling water, just warm. Be sure to shake off all the water from the piece though, THAT is hot. I didn't and burned my fingers :( The material goes stiff quickly out of water, so you have to work fast.
Making a mold of the pen end. Don't mind the homemade pop stick tools :P I just wanted my mold to be more even is all.
Ta-dah! A nice shiny new cupcake mold! Wait, there's something weird in the middle. Pif, I forgot to plug up that hole in the pen. Since Oyumaru is reusable, the material did not go to waste. I simply threw it back into the hot water again and repeated the process.
Here are some finished molds. The molds are not very flexible, but if you dust some talc powder or cornstarch into it, you clay should pop out all right. There might be some distortion during the process though.
I've not tried this material with resin but I will when I gather up enough courage to stop putting it off :/
Despite its limitations, Oyumaru seems like an okay molding material. It works if you're too poor or cheap (like me) to buy silicone and are willing to work around its limitations. I do like that I can reuse it if I made mistakes but the biggest downside for me is that baking with it is probably unadvisable, considering it turns all gooey and soft in hot water... I might try a workaround by boiling smaller clay pieces in it till they're hard enough to pop out of the mold without distortion and then baking them.
I'll definitely give silicone a go one day when I have more money :P
Toaster oven rant:
I've found out that my toaster oven is a lousy piece of crap. I put my shiny new oven thermometer in it and it shows me that my oven likes to heat up and up and continue heating up. I even turned the toaster oven dial to like 50 degrees, but the temperature kept rising after it hit the 50 degree mark. I turned off the oven after the temperature hit 140. Well, this explains why I burn my stuff and why people talk about baking things like those cookies I made earlier for 20 mins or so, where my test cookies burned after I left them in for more than 50 SECONDS.
I've also found out after doing some research that if the temperature is too high, the outside cooks faster than the inside, and may even burn while the clay inside remains raw. This can cause the plasticizers from the raw clay to eventually leech into the outer clay layer and cause it to break down eventually. Also I've noticed that lemon canes cooked in that higher heat tended to be more brittle than ones baked at the right temperatures.
Since I don't want to spend money to get another oven at the moment, I've been sitting in front of the oven and turning the oven off when the thermometer hits 140 degrees and turning it on again when it falls to 130.
Anyway, enough oven rants. I'll be posting up photos of my Totoro cream puffs soon, hopefully tomorrow. I've been trying to get a decent picture of them for days >_<