蝸桿軸，Z軸微進給

Installed this on my mill and the Z-axis moves much smoother now with no binding. The threads on the shaft are cut precisely and engage perfectly with the gear. Exactly what was needed to fix the backlash issue.

The machining on this worm shaft is noticeably smoother than the original part, and the threads engage perfectly with the brass nut on my mill. I've been able to take much finer 0.001-inch cuts during setup without any backlash or binding.

The replacement worm shaft dropped right into the Z-axis assembly on my mill, and the fit is snug with zero play. Threads mesh with the gear smoothly, so the fine feed now moves in tiny, predictable increments instead of that annoying chatter I had before.