book collections email follower instructable user

Step 8: Make a Mold From the 3D Printed Ring

Take a chunk of mold-making clay and cut it into a roughly 2" x 2" x 0.75" shape. Push your ring that you've sanded to a high polish into that, roughly halfway, as shown in the first picture.

Then push the clay up to the ring on the inside and outside as flat as you can, and make a box around it so that you can pour the silicone over top of it. Some divots will make sure that you can always line your two halves of your mold up well down the road, and a channel around the outside will help prevent leakage when casting.

For the mold, I used the silicone (yellow) and hardner (blue) shown in the third and fourth pictures. I'm quite sure there are other options, but these worked very well.

I then mixed these together, and threw them in a vacuum chamber for a few minutes to get all the bubbles out as shown in the fifth picture.

I was told to pour the mold starting at one corner, and just let it slowly cover the ring. Once this was done, I let it harden for 24h, then carefully peeled and cleaned the clay off the other side without removing the ring from the mold or disturbing it in any way, then sprayed mold release over everything, then poured the other half in the same original box made of acrylic pieces and hot glue (or whatever is handy.)