Ice and Chocolate Molds With 3D Printing

So you are one the us geeks who were always searching for cookies shaped like Donkey Kong or soap shaped like computer mouse? Well search no more, because you can do all of this in house...I present my series of GEEK silicone molds easily done in your own home with awesome 3D print technologies...

For the first GEEK mold instructable I've chosen the Star Wars Stormtrooper mold for "casting" ice "cubes" or chocolate or anything else you can think of - the cool thing is to fill the mold with some fruit syrup and have some improvised popsicle...

UPDATE: please 3D STL model of Stormtrooper attached below - I totally forgot to add this in case someone wants to 3D print it by himself...

Step 1: 3D Model/sketch

As always with 3D printing, you can not do anything without 3D model created by 3D modeling or 3D scanning - I use Rhinoceros for all of my modelings but you can use anything you like - there are bunch of free modeling tools out there so go and explore. One thing you need to take care of, when talking about 3D printing, is creating a so called "water tight model" or WTM. 

This WTM in plain words marks that your design should have no holes and "leaks" where water could came out if in theory you would fill it up. You should not have objects without volume (plain surfaces or curves) - everything needs to be a solid so the printer can make it. 

The best way to make sure you have no errors (holes, overlapping triangles, bad edges, etc) which could affect quality of the print, is to use some of the specialized softwares for 3DP preparation - a good free solutions are MiniMagics and MeshLab.

Step 2: Tools and Materials

Once you have your design its time to do some 3D printing - my favorite technology are definitely ZPrinters, composite powder based technology which need no support, very fast and affordable - one "negative" side is that it's not the plastic but who cares, most of the parts I do are solids with fine details which this machines can do without any problem. ZPrinter (now they are called ProJet X60) parts are tough, durable and can be printed in full color - it works for me.

OK to get back to the mold making, here's what you'll need...

Tools
- 3D printed models
- some type of mold frame, I used this round plastic pipe part, you can use whatever you like/have
- spreader
- plastic container for mixing

Materials
- two-component food grade silicone/rubber
- common modeling clay

Step 3: Mix and Pour

Now, take some of the modeling clay and fill your frame approx. 1 cm high - it really does not matter, this is just for your models and silicone not to drop out of the frame. Actually you probably could to it without any clay, just laying everything on the table but this is a better and "cleaner" way. Arrange your printed parts and push them gently in to the clay.

One digression - if you are making a two part mold (which I'll demonstrate in another instructable), at this point you would be pressing printed parts deeper in to the clay, to the point where you would like to separate the mold. But let's leave this for this second instructable for now.

Then just mix the silicone based on the manufacturers instructions and pour it over the whole thing...then leave it to dry.

Step 4: Release the Mold

After your silicone dries, take it out of the frame and remove the clay. Then gently push and spread the silicone so your printed parts come out - you don't need to be very careful here because good thing about the silicone is that it's very stretchy and will take a lot of tension...

After you remove the printed parts, clean your mold - you can even wash it in dishwasher - it should hold up to 250°C - at least this mine I used...it can easily be used for baking also.

Step 5: The Final Result

And now the fun starts - pour something in and let it friezes - I used plain water to get this "ice cubes" shaped like storm troopers but you can mix anything you like.

Stay tuned for more mold making experience done in your home. Geek on!