[turbozee]

I'm taking apart my Nakamura Tome TMC-3 to retrofit and pretty much look over every component of the machine. I took off the Z servo and found this:

nakamura - z servo - Album on Imgur

I see straight cut gear teeth. I'm confused on how they're eliminating/minizming backlash. I was thinking there would be some sort of harmonic drive, but to my surprise it's just gears. Any ideas?

[Eldon_Joh]

You can actually preload the gears and achieve zero backlash, however you must have properly engineered lubrication otherwise the gears will wear. basically the oil film thickness and preload needs to be just right, so that during operation the oil film and the applied torque pushes the gears away from each other so they don't contact each other.