help with servo motors Please.

[JAZZCNC]

Contacted Marchant Dice asked for a quote saying gantry was 120KG, I was quite surprised they suggested a nema 23 small nm with a 12:1 gearbox. I thought that rather weak.

Well yes and no the 12:1 ratio increases torque approx 12 fold. I presume they where working on using R&P which if using figures like I quoted further down would give a speed around 11mtr/min and a pitch around 11-12mm which is ok. Working on a conservative 800 micro steps and 12mm pitch then you'll have resolution in the 0.01mm range.

The only problem I see with this setup is higher backlash, because you'll have backlash in the gearbox and backlash from the R&P. Thou For cutting stone I don't think this will be an issue.!