This week’s materials assignment called for the “hello world” of mold making: the hand casting. For the mold, I used MoldGel Regular Set alginate, and the finished casting was set in pottery plaster. The process went smoothly, for the most part, but a few things could have gone more smoothly:
- Hand-mixing even small quantities of alginate is not such a good idea. I was left with lumps and bubbles that showed up as pits in the plaster casting.
- A 1:1 mix of alginate to water by volume leaves the alginate way too thick, and since it sets so quickly there’s not a lot of time to revise the ratio before you have to pour. Better to listen to the product’s information sheet than vague rules-of-thumb.
The (unsettling?) photo above shows the inside of the alginate mold after I removed my hand. The photos below show the finished casting in various stages of removal from the mold.