i made the rod for my crank mechanism, and i printed it out and it didnt really work. this was because it was mounted sort of inside as the pipe, so it couldnt do a 360 degree rotation without hitting the pipe. i printed this thing that boosts it up a bit, while adjusting the rod size a lot and eventually it worked? i mean i thought it would work, but my crank has this weird think where when the crank is down its going up then it is pointing down. due to all of this, i kinda ended up switching to a rack and pinion, and that was funny. i did a bittings of work on rack and pinion, but i did a solid half and hour of research on how a rack and pinion / gears work cause i havent worked with them before. apparently theres thing thing called a module, which makes sure that gears mesh with each other. i managed to make a good rack and pinion, and they mesh really nicely once i printed it.