my first CNC router build

Hello everyone,
Newbie here.
so i have built a 3axis cnc router 1200mm X 700mm X250mm
3 x nema23 23GHS9430B , 3AMP , 4.8V. 1.8Deg/step
3 x driver DM542A
Breakout board DB25-1205
Power supply is 240vac in 36v out
Parallel port connection

I'm using mach3, i can get all axis moving manually, but when i run set of g codes the motors don't seem to be set up correctly, i cant seem to get my head around setting the stepper motors up, dip switches and the motor tuning. The driver dip switches are set as follows
1 on
2 on
3 off =Peak 2.84A 2.03A RMS(motor rated at 3amp)
4 off for half currant
5 off
6 on
7 on
8 off =400 pulse/rev

x axis moves using a Ball screw SFU1605-1200
Y SFU1605-700
Z 250mm Screw slide table

Any and all help is greatly appreciated

According to the table in my DM542T handbook and the online link I've found for the DM542A, OFF, ON, ON, OFF for switches 5 - 7 is 2000 pulses/rev not 400. You want OFF, ON, ON, ON.

Kit

Thank you sir
So with the dip switches set as you have stated in your reply. In mach3 motor tuning, for steps per and velocity mm's, my calculations don't seem right, can you help me with this or point me in the right direction please

My thinking is, if 2000 pulse/revolution = 1 full rotation = 5mm travel, for a feed rate of let's say 300mm/min I'd need to setup my motor tuning to steps 12000

All help is Gratefully appreciated

Quote:

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Originally Posted by andydavidsmith40

Thank you sir
So with the dip switches set as you have stated in your reply. In mach3 motor tuning, for steps per and velocity mm's, my calculations don't seem right, can you help me with this or point me in the right direction please

My thinking is, if 2000 pulse/revolution = 1 full rotation = 5mm travel, for a feed rate of let's say 300mm/min I'd need to setup my motor tuning to steps 12000

All help is Gratefully appreciated

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Ok well first because your using the parallel port then I suggest you change the drive settings to 5 =on 6=off 7=on 8=on this will give you 800 MS. This is a better micro stepping figure for the parallel port which as a low frequency which will limit your max speed.

The number your looking for isn't steps per Rev it's Steps per mm if you are using Metric units. So to calculate the correct steps per setting divide the MS by the ball screw pitch 800/5= 160 Steps per mm.

Now because you are using the parallel port and only running the motors with 36Vdc and with a 5mm pitch then your Max velocity won't be high. I suggest you start your motor tuning around these figures, Velocity = 3000 and the acceleration to = 500. Provided your machine is set up correctly with no axis binding then with the above specs of 5mm and 36Vdc then you won't get much more than 4500-5500mm/min max Rapid feed rates.

When you tune motors only adjust one setting at a time and then test. Start with velocity and adjust until the motors stall, then back off by 25%. Do the same for acceleration.
This should give you a nice stable motor tuning setup.