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mklb
03-27-2005, 08:41 PM
I need help!

I run Mach2 on a DIY cnc machine that uses X, Y, Z movements like a milling machine, but is acutally a lathe for turning pool cue shafts.

My first dilemma is setting up an A axis. I have a stepper hooked up to the spindle of my lathe. I want to use it to index for inlay work. The problem is that I do not know how to command it. When I write G1 A90, the axis tries to move to a linear position of 90. I have the axis set to angular in config>logic, but it still does not work properly.

My second dilemma is that I want to use the same stepper as a spindle motor for turning operations. I have tried numerous configurations and had no success.

I am rather self taught, and can't figure this out. any help would be greatly appreciated.


Royce

ger21
03-27-2005, 09:29 PM
Do you have your steps/unit set correctly? What do you mean it's trying to move linearly?

I think you'll need 2 seperate configurations if you want to use it as the spindle. You'll have to disable it as A for spindle use I think. For spindle use it should be controlled by using S. CHeck the manual for more info, as I'm just guessing here.

mklb
03-27-2005, 11:13 PM
Ger21

I know I am looking for two different setups, I want to save them as different profiles so that I can open Mach2 with one profile for turning and the other for inlays.

Since my last post I have been able to make the a axis work. I select a axis in the port setup and designated the correct output pins. (I had done all that before). I set A to angular in Logic configuration. I was able to command g1 A.5, and get it to rotate to 180 degrees. When I go to A1, it comes aroung to the top again, but the DRO shows 1.000. I did some inlay with this and it worked by dividing the number of inlays in the full circle into 1. Four inlays would be .25, .50 .75 and 1 or zero again. I don't htink this is right, it just seems odd. I followed the manual although I can't seem to find the pages right now. It is getting late, and the pages are beginning to all look the same.


I have not been able to make the stepper spin as though it is a spindle drive motor though. I have played with the pulley settings and the motor tuning, but I get yellow flashing lights when I enter an M3 or M4 to get the motor running. I will have to pick it up on Tuesday, when I can get back to the machine.


Royce

ger21
03-28-2005, 07:33 AM
M3 or M4 are usually used to turn on a relay. Not sure if that's how you would start the stepper spindle?
Here's what the manual says:


5.6.6.3 Step and Direction spindle controller
To configure the spindle motor for Step and Direction control, check the Spindle Axis
Enabled boxes on the Port and Pins, Printer Port and Axis Selection Page tab (figure 5.1).
Leave PWM Control unchecked. Don't forget to Apply the changes. Define output pins on
the Output Signals Selection Page tab (figure 5.4) for the Spindle Step and Spindle
Direction. These pins must be connected to your motor drive electronics. Apply the changes.
Define External Activation signals in Ports and Pins and Configure>Output Devices to
switch the spindle motor controller on/off if you wish to take power off the motor when the
spindle is stopped by M5. It will not be rotating anyway of course as Mach2 will not be
sending step pulses but, depending on the driver design, may still be dissipating power.
Now move to Configure>Motor Tuning for the "Spindle Axis". The units for this will be
one revolution. So the Steps per Unit are the number of pulses for one rev (e.g. 2000 for a
10 times micro-stepping drive or 4 x the line count of a servomotor encoder or the
equivalent with electronic gearing).
The Vel box should be set to the number of revs per second at full speed. So a 3600 rpm
motor would need to be set to 60. This is not possible with a high line count encoder on
account of the maximum pulse rate from Mach2. (e.g. a 100 line encoder allows 87.5 revs
per second on a 35,000 Hz system). The spindle will generally require a powerful motor
whose drive electronics is likely to include electronic gearing which overcomes this
constraint.
The Accel box can be set by experiment to give a smooth start and stop to the spindle. Note:
that if you want to enter a very small value in the Accel box you do this by typing rather
than using the Accel slider. As spindle run-up time of 30 seconds is quite possible.

mklb
03-28-2005, 10:26 AM
Ger21

I think I have gone through the manual so many times it is all running together. I have set up all of these parameters.

I checked the spindle axis enable box.

I defined the output pins for spindle step and direction.

I defined external activation signals.

I set the spindle axis units in motor tuning. I used 1600 for the units (200steps *8 for Xylotex microstep).

I set the Vel box to 3.333 (200rpm max/60)

I have played with the accel box, both low and high.

When I go to the MDI screen and command S100, it changes the DRO speed to 100 just like it is supposed to. But when I try to start the spindle, all I get is a yellow light flashing in the DRO display. If I hit reset or type in an M5 command, it will stop. I get the same yellow flash if I command an M3 or M4.

I have also played with the pulley settings. My actual pulley arrangement on the machine is 1 to 1, so I don't need any reduction or multiplication. I currently have the software set to pulley #4, with a max speed of 1000.

If there is anyone out there who has used Mach2 to drive a stepper for spindle control I would love to see your setup. I know it is something simple that I am not doing right, I just don't know what it is.

I love this software, but this is an important function that I must have. I have not purchased the activation yet because I have not been able to get this to work. I really like everything about the program, I just need to be able to get this to work.

Royce

mklb
03-29-2005, 10:14 AM
Boy do I feel dumb!!

I went through the setups again last night and I found my error. I had not changed the port # from 0 to 1 for the spindle. I had set the step and direction numbers properly, I had just not told it which port is was coming from.

So anyway, the spindle is now spinning properly. I have to work out the speed, and make sure that it is right, but I will have to wait until tonight for that.

Thanks to all for all your help. I know I found my own problem, but I would have still been thinking there was some setup that I had not found if you guys had not pointed me back in the same direction.


Royce

ngr1
11-27-2009, 08:19 AM
Hi Royce, thanks for sharing ur experience. I am trying to do the same thing with my machine which is in transit now.

Refer to the following link which may help.

http://www.machsupport.com/forum/index.php/topic,11422.0.html

Sounds like ur missing an indexing component to do ur inlays.

Let me know what u think.

Norman




Boy do I feel dumb!!

I went through the setups again last night and I found my error. I had not changed the port # from 0 to 1 for the spindle. I had set the step and direction numbers properly, I had just not told it which port is was coming from.

So anyway, the spindle is now spinning properly. I have to work out the speed, and make sure that it is right, but I will have to wait until tonight for that.

Thanks to all for all your help. I know I found my own problem, but I would have still been thinking there was some setup that I had not found if you guys had not pointed me back in the same direction.


Royce