Gear Widget 90 Degree Transmission

thingiverse

Another sweet gear widget I crafted. The fantastic thing about this one is that it transforms rotational motion 90 degrees at a precise 1:1 gear ratio. Gears like these are genuinely fascinating, yet they're not very practical due to their 45-degree pressure angle between gear teeth, which is quite high - similar gears and cams don't function well with pressure angles above 30 degrees, plus the sliding of the teeth generates excessive friction. As a toy, though, it works surprisingly well! And it's fun to watch. A couple of notes: I printed it without the tiny washer additions, so if you turn one of the gears in the wrong direction, the other will pop out. But turning the same gear in the opposite way keeps it securely in place! I quickly designed a few press-fit washers that should keep it locked in (it's actually 1/32" larger than the shaft, but for some reason, my printer spits those out as quite tight press fits). I haven't tested the washers yet, so they might not even work, but it's worth giving them a try.