I want to build the track system completely from scratch in order to keep cost down. The chain I have on hand is a 25H chain, pretty small.

After thinking about it a bit, I decided it might be best to run two chains separated by the part you see below. I will only place this on the solid links, not the ones between holding those solid links together. After I do this, I can 3D print a nice "sprocket" that fits the track well.

The part is simple enough that if the plastic does not hold up running around my house on carpet I will just sand cast them out of aluminum.

This was printed on draft mode with 100% infill to make it very solid. The idea is to use rivets to attach it to the chain. The curved bottom will fit into a sprocket while the chains are kept from sliding off by a guide that will also be printed into the sprocket.

In other news, some but not all of the parts for the audio recognition system arrived today, still waiting for the rest of it before I get that system constructed.

After looking at the bar stock that I have and my old hack saw, I also ordered a small chop saw designed for cutting aluminum at 0-45 degree angles. This should simplify and speed things up tremendously during the chassis/body build.

Tools are never a bad investment :)