3D Printing a Mold for a Slipcasting Mold

I have always loved the 3D model of the 'Vaas met oor' (Cup with ear) by Joris Van Tubergen. A couple of years ago I did my first attempt to make ceramic cups of the model. I succeeded and love drinking my coffee from these cups.

Recently I wanted to make some more of them. Only thing: I did not like the handwork that was needed to create the mold.

Inspired by the option 'Mold' in the software for my Ultimaker 3D printer (Cura) I started to think about printing a mold for a mold.

This Instructable shows what I did to print a mold for a mold and how I was able to use it.

Create a mold in your favorite 3D modelling software.

I used Autodesk Fusion 360 to substract the 3D model from the cup from a cilinder. I cut that model in two and I added small spheres on one part and two small sperical holes on the other part so the 2 molds can be easily positioned correctly.

So here's the trick. Print the model hollow without a bottom or a top.

Preferably, if your slicing software provides the option to spiralize the outer contour, that would be the best.

DO NOT REMOVE YOUR MODEL AFTER PRINTING!!!

With your model still on the printer platform, prepare your plaster. This Instructable by Eckert perfectly shows how to mix plaster like an Italian pro :)

After the plaster has cooled and solidified, you can remove the model from the platform.

Gently cut through your 3D printed mold. It does not matter when you cut too deep, it's just the outside from your mold.

Remove the 3D print and let your mold dry.

(In case you're having difficulties removing your 3D print: consider using a paint stripper. By heating up your 3D print it will become flexible and eventually easier to remove.)

You are now a digital craftsman!

You are able to create a mold without too much manual work :)

You can now cast the cups in the preffered material.

New to slip casting? Check out this Instructable by Chanw612.

(The pictures show briefly how slipcasting works: poor stoneware or ceramics into your mold, wait for ±20 minutes, poor out the stoneware or ceramic and look!: *MAGIC!* There is a layer of stoneware in your mold :) Wait for another 20 minutes and gently open and remove your mold. Let the model dry before you continue.)

To finish: sand, bake, glaze and bake your model and enjoy your coffee!

Be aware: during the baking proces the model will shrink. The 3D files used for this Instructable will make lovely espresso cups :)