sorry for the vague subject line, but I am not sure how to qualify this one.
I am in need of creating a reusable mold that will be approx. 3.25" in diameter (not a true circle), and approx. 2.5" deep. Basically, it will be a custom-fitted item that will go into a cupholder of a specific vehicle, to where it fits that cupholder like a glove. It has contours, and has a few outcroppings (rubber "bumpers").
To get the cupholder's shape, I used playdoh, and covered the sides of the vehicles cupholder with olive oil (a handy release agent). This has worked, but when the playdoh dries, it shrinks and cracks. The reason I believe I need it to be dry is that my plan was to then take what I made of playdoh and use it to make the reusable mold; I would take this item and either press it into plaster of paris, or whatever anyone here recommends the mold to be made of.
The mold would be used to make items out of resin.
Does anyone have a better way of going about this?
Since you are already using a release agent, why not use RTV silicone rubber instead of Play Doh. If your still needing something like your original plan try Alumilites mold putty. Another possibility since it is more than likely an ABS plastic could be to use Amazing Remelt.