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7. Moulding and casting

This week’s tasks:

a) Create a 3D mold tailored to fit the stock material and tools you plan to use

b) Mill your design and cast it using the chosen material

This involves using a wax material that will be engraved in using the milling machine which includes a tool that drills through it. There are many types of drills that can be used that have different sizes and shapes depending on your design and its complexity. After making the mold, you can use several materials such as silicone or resin to make your product. This is pefect for making small pieces such as magnets or keychains.

I took this opportunity to make something for my business that will help in the long run which is a stamp. This entails a one-step process since I won’t “cast” anything on the mold other than pouring silicone over.

I first started with converting my png logo into SVG so I have simple lines to work with. Bringing it into inkscape, I realized I there were too many jagged/ unnecessary lines. So inkscape was the perfect software to manipulate those lines. I did so by “breaking” them into their own individual shape and deleting what I didn’t need

After cleaning up the lines, I send it over to Fusion to give it some depth and to add a base

Then I brought it to TinkerCAD to make the final design for the mold. The process involves making the logo a “hole” and merging it to the square that serves as the space I’m using from the wax.

Join the two

We then export it the milling software to create the tool path

Here’s the process of the milling of the wax. After it’s done, take it out and dust away the excess wax and store it for future use.

Next thing we do is prepare the silicone to pour in the mold. There are two parts to it:

The ratio is 1:1 so I weigh them both to 15 grams each in separate containers.

The next step is to mix them together thoroughly for 5 minutes.

Once that’s done, you can pour the mixture in the mold. Make sure to make the amount of silicone mix enough for the size of your mold so you’re not short nor excessive.

After it’s filled to the top, use a skewer to poke the bubbles that formed in the mixture while pouring.

Do this while it’s still wet, otherwise once it’s dried up, the bubbles will still show and it won’t be the smootheset looking silicone.

Then let dry for at least 24 hours.

Once dry, safely remove the silicone from the mold. This step is pretty easy and satisfying.

Cut of the excess using scissors

And here’s the final product!

You can use any ink stamp pad

I did some tests on paper and cardboard and I think they turned out really good.

In the future, I’ll hopefully make more stamps of different designs and maybe even 3d print a holder for the stamp.


Last update: July 20, 2024