Servo Motor

[Ed Williams]

I asked this under servo motors with no replies so I thouht I would ask here. I was wondering if these motors would work on 2x3 table. The gantry weights 120lbs. It has thk bearings and ball screws. It has 5tpi screws. I was going to use 2 to 1 pulleys.
Thanks Ed

Globe PN (custom): 537A-214
Frame Size: Nema 23 (non-square mounts though)
Static Torque: 190 oz-in
No Load Speed: 4504 RPM
Max Bus Voltage: 42 VDC
Max Continuous Current: 3.4 Amps
Peak Stall Current: 6.7 Amps
Shaft Diameter: 0.25"
Encoder: HP 1024 PPR Optical Disc Encoder

[Al_The_Man]

So one motor rev = .1 travel. That seems a heavy gantry weight for a 2x3 table?
The weight on accel/decel (inertia) will probabally be your bigest limiting factor.
If you can reduce the Gantry weight it would help.
If you are routing only, you do not require quite the same rigidity as for milling.
with 4000 rpm you have a bit to play with for reduction, the inertia ratio between motor and load will be reduced by the Square of the reduction, so every little makes alot of difference.
Al.

[Ed Williams]

I have a 10 inch travel on the z. It has a heavy Thompson dual 1 inch slide bearing to keep it rigid. That is a lot of the weight. So if you could in layman’s term suggest what gearing I should do.
Thanks Ed

[Al_The_Man]

At the suggested gearing of 2:1 that will give you a max of 400"/min rapid travel, If you require this or higher feed rates and decent accel/decel then I don't think those motors are going to cut it.
I think I would be looking at a min of 300 oz/in or higher.
If you download one of the free sizing programs it will give you an Idea of what ball park you should operate in.
Many of the servo manuf. offer one, the Kollmorgen one is fairly good from MotionVillage.com
Al.