Rail Prosthetic

This week’s goal was to create a mold and cast something out of it. I decided to make a rail prosthetic.

I began by dimensioning and sketching how the new rail would fit on the existing rail. Once I had my sketch concept together I then used Rhino to create my 3D model.

The top image is my complete 3D model and the lower image is the negative model I used to cast the top half of the rail.

Next, I glued two pieces of the blue foam together to get the correct thickness. I used the Shopbot to mill the top and bottom negative of my mold. I used the 1/2” flat bit for both my rough and finishing paths, I was happy with the result.

I aligned my pieces and since there was no gesso in the lab I used soap instead. Then I used gorilla glue and clamps to weld the two pieces together, measured the amount of hydrostone powder needed and then poured the hydrostone. Shout out to Andrew and Oliver for helping me put together the foam together.

When I created the model I didn’t think to seal the edges so I had some capping. A quick trip to the GSD wood shop and that was taken care of with the band saw.

The final rail. It fits the existing rail like a glove and the bone conductor slits work great.