TheGreatestMoo

Yeah the track fell off several times yesterday. The pointy ends of the track seem to snag the ground when you try to turn which just causes the wheels to roll over the guide teeth and pop off the idler. Since the idler wheel has a spring to keep tension sometimes it cant hold it tight enough but it also keeps stuff from breaking, you can easily slip the track back over the idler and keep going. After this video I removed a link from both sides and it happened a lot less. I think it also had something to do with one of my suspension arms actually broke, but the way its designed the piano wire spring actually holds the arm in place and takes the whole load of the wheel. After that broke one of the front wheels was a little wobbly which allowed the teeth of the track to slip over it. I super glued the spot which broke but I might try another method of suspension similar to what I did to my Leopard 2.

Attached is a picture of the current suspension setup. A thin gauge piano wire is bent into the arm to create the spring. The 3d printed arm runs into a bushing in the lower hull and that's the point which broke off. My Leopard 2 uses a shoulder screw through the arm, with an offset hole where the piano wire comes out. Still allows the arm to ride on the spring within its range of motion. I can do the same thing with the Scorpion, it would be much stronger.

The tracks themselves are the most amazing part about the whole tank. They are 3d printed with all the holes drilled and ready to pin... one of the holes is smaller then the rest to grab onto the pin. it is amazing how good 3d printers are at doing things like that. In my old 1/6th scale scorpion that was the HARDEST part by far, and I still never got it right. This 3d printed one the tracks were like no difficulty what so ever to make. It was about 12 hours of print time for the whole track set of about ~130 links. I originally used oversized tracks because I didn't know how strong they would be, but then I went to nearly scale sized tracks. These are still a little longer then the real ones tracks but its about the same width now. They seem to be very strong as you can see in the vid.

As for the detail panels, almost all the details are printed directly onto the panels, it saves a lot of assembly time. They are printed 100% density also so you can grind off pieces you don't want to use very easily. I forgot to mention but the whole tanks made of normal ABS filament, even the final drive gears. I could CNC machine them from thin stock plastic but I don't really have much access to my CNC anymore, I since moved into a 1 bedroom apartment. The main printing time is just the entire project as a whole, there is lots and lots of pieces.

I'm emailing a couple 3d printing companies to get some quotes on how much it would cost for the whole deal.

Forgot to mention nearly the whole tank has mini bearings also, like in all the idlers and wheels, drive sprockets, and even the gun elevation. The transmission does not though because it uses the stock Tamiya science gear set which I think are nylon gears, they are very tough, it does use little brass bushings though.