Tarmo4 6.5x Gearbox

thingiverse

# CORRECTED -- Fixed issue with gear overlap Wow, that was embarrassing. I was so focused on making sure that the gears meshed on the train, that I totally missed the overlap between the front and rear. Corrected now and should be functional. Unfortunately, I had to give up a little bit of the ratio to make it work. Original description follows (with minor edits)... ---------- Hi Everyone -- I've adapted the gearbox to allow the use of higher kv motors. Specifically, mine is 3900kv and tended to cog with the original gearbox. This one is ~7:1 (4:5, 2:3, 12:42) and so far has been working fine. I'll post videos on instagram when I get a chance. I've done a few iterations on the input gear. The first used a direct drive 'D' slot and connected directly with the motor. That worked.... for about 100 m, give or take, before it ripped out. It was tight when I put it on, but that didn't make a difference. Instead I've provided two options that use a pinion gear to connect the motor shaft to the gear box. The gear should fit without requiring a press, though that is an option. Alternatively, if you feel the pinion is too loose, a drop of hot melt glue should keep it in place. To use this, you'll have to print the modded middle and rear chassis sections as the new gears push the motor back and to the right a little. Your front section should work just fine. The pinion required is 12T, 48P with a shaft that will fit the 3.17mm motor spindle -- they're pretty cheap, about $5 or so.