Purchased this unit from Singles-day sales in AliExpress. Unit is with 130mm chuck and Nema 34 Stepper.
Everything is pretty much as expected, including backlash issue.
I stripped all to parts and backlash is due fact that worm- and main-gear are not close enough to each others.
Gear and worm seems to fit pretty nicely together
I´m thinking how to create shift main axis. It´s bit thin to machine stuff away and make eccentric bushings.
Also I´m puzzled to weld it.. Most likely its casted aluminum. So just weld bit material on side and machine eccentric location for bearing and sealing.
Outside is easy, just make eccentric cover.
So any suggestions?
Cheers-Jukka