[laserpilot]

Hi Guys, thanks in advance for all replies.

I have a new Milling Machine build I have started. Design is finished, just need to finalise what size ball screw I will use on the "Y" Axis. (I always call my LONG axis the "Y"... is this correct by the way)

Long axis is 1700 mm long overall. I have 2 choices for the screws.

1/ 16mm dia, 10mm pitch max allowed revolution 650 rpm

2/ 25 mm dia, 5mm pitch max allowed revolution 1400 rpm

The machine will mostly be used to bore holes in 20 mm Aluminium plate Drives are Geko with Nema 24 (large case nema23) 650 Oz motors

What screw would be best do you think given the 25mm screw is double nut and twice the cost at $500

Thanks again

[iamnot.romeo]

How much HP does spindle have ?

[Mr3D]

Y axis is going back and forth, X axis is going left to right, Z axis is going up and down.

About the screw, you have to think about resolution too, you will most likely have 2000steps/rev when microstepping the stepper, your theoretical resolution with 10mm pitch will be 0,005mm, and with 5mm pitch 0,0025mm (pitch divided by steps/rev). Don't forget the backlash too, sounds like the 25mm screw got a pre-load too. I vote for 25mm screw any day.

[chevydyl]

I'm using a Rexroth 25mm screw with a 10mm lead on my x. 0.00019in resolution with a 2000 microstep driver. I think it's enough resolution for me. I would however rather have that same screw in a 5mm lead cause the resolution then becomes 0.00009in. I have a 14mm 5mm lead screw for my Z axis but now that I have the beastly 25mm Rexroth screw I want to change it out.

Edit: I can never see myself needing to make a cut to take off less than 190 millionths of an inch.... just sayin