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Fastest1
08-15-2011, 08:23 AM
I am running some old steppers that are fully functional (escap P532) http://www.astrosurf.com/durey/p532.pdf
Judging from the spec sheet, I would think they were 100 steps per revolution. Can someone confirm this?

wendtmk
08-15-2011, 10:23 AM
This forum is for discussing Keling products. You will probably get a better answer if you post your question in the Stepper forum, further down the list of forums.

Mark

rowbare
08-15-2011, 10:26 AM
You are correct the pdf states: Step angle: 3.6°

bob

Fastest1
08-15-2011, 10:34 AM
This forum is for discussing Keling products. You will probably get a better answer if you post your question in the Stepper forum, further down the list of forums.

Mark

Mark, I appreciate the advice and I have asked this question worded different ways across the zone with no response. I am using a Keling 5056D and trying to determine the steps per rev setting. Of course my next question will be, where is the setting for under 200 steps per rev?

wendtmk
08-15-2011, 10:44 AM
I think you might be confusing steps per revolution with microstepping. Steps per rev are usually set in your CNC control software.

Mark

Fastest1
08-15-2011, 12:26 PM
I think you might be confusing steps per revolution with microstepping. Steps per rev are usually set in your CNC control software.

Mark
This is my third or fourth machine to misconfigure, so you could be quite right about my confusion:confused:. Actually Mach3 has a setting on steps per unit (inch or MM whichever you set) however the digital driver asks for steps per revolution which I believe is different. My setting in Mach 3 with a G540 running this same stepper is 101,660 steps per inch (my steppers have a 10 to 1 gear reduction). The resolution was much higher than is useable for me and I believe it sacrifices speed. These steppers are 100 steps per rev as opposed to the 1.8 or 200 steps per rev. Anyway I dont mind being wrong if someone can help with a solution for movement. Btw, every time I configure a machine, I think I wont have this set up issue next time! Sure enough I can be just as confused on the next build. Of course I change all of the electronics each build and have gone from a Hobby Cnc Pro (kit) to a G540 and now trying a C35 & 5056D combo.

wendtmk
08-16-2011, 12:03 PM
Fastes1,

I'm not familiar with Mach setup, because I use EMC2. In the stepconf wizard on EMC2, there's a section for each axis configuration for motor steps per revolution:

LinuxCNC.org - Configuration Wizard for Stepper-Based Machines (http://www.linuxcnc.org/docview/html/config_stepconf.html#sub:Axis-Configuration)

Perhaps there's a similar window in Mach?

Mark

Fastest1
08-16-2011, 12:38 PM
Mark, there is a similar settings box within Mach3 except it is for steps per unit (the unit of measure mm or inches is determined by the user on original set up). What I am referring to is a setting on the digital driver from Keling. I believe it asking for how many steps per revolution of the stepper. In my case since it is a 3.6 degree stepper, it naturally has 100 steps per revolution. I dont see a way to set the driver for less than 400 steps per rev. When setting the steps per unit in Mach3 with the G540 (a 10x microstepping controller) it was needing 101660.38 steps per unit (inch). This equates to .00000984" travel per step. This was a little finer than needed with the G540 there was no way around it. That should equate to 10166.038 steps in single step mode still giving me a resolution of .00009837. This is still such a high resolution, it costs me speed. Maybe I should be considering 1/2 step. I could be having a communication issue between my BOB and the driver, I am not sure just yet. Confusing to say the least but keep the questions coming, it has to be something simple. I have tried jumpering enable switches, unjumpering and every other thing i could think of.

doorknob
08-16-2011, 01:36 PM
I don't have that driver, so this is just a guess.

However when you say "I dont see a way to set the driver for less than 400 steps per rev.", I am guessing that you are looking at a chart where you set DIP switches to indicate the steps per rev.

If that is the case, then I believe what is really happening is that the driver assumes that you are using a 200 steps per rev stepper motor, and so if you set the driver to 400 steps per rev what you are really doing is setting the driver for "half-stepping mode".

Similarly, if you set the DIP switches for 800 steps per rev, you are actually telling the driver to go into 1/4-step microstepping mode. And so on.

Since your steppers are actually 3.6 degree steppers instead of 1.8 degree steppers, that equates to 100 steps per rev instead of 200 steps per rev.

So, my conclusion is that if you set the DIP switches to 400 steps per rev (half stepping), with your motors it is actually only 200 steps per rev, and that is the figure that you would need to use in conjunction with your ballscrew pitch to input the proper figure into Mach3. And so on for the other DIP switch settings.

As noted above, this is just conjecture on my part, but I'm relatively confident that it's correct.

hoss2006
08-16-2011, 02:38 PM
I don't have that driver, so this is just a guess.

However when you say "I dont see a way to set the driver for less than 400 steps per rev.", I am guessing that you are looking at a chart where you set DIP switches to indicate the steps per rev.

If that is the case, then I believe what is really happening is that the driver assumes that you are using a 200 steps per rev stepper motor, and so if you set the driver to 400 steps per rev what you are really doing is setting the driver for "half-stepping mode".

Similarly, if you set the DIP switches for 800 steps per rev, you are actually telling the driver to go into 1/4-step microstepping mode. And so on.

Since your steppers are actually 3.6 degree steppers instead of 1.8 degree steppers, that equates to 100 steps per rev instead of 200 steps per rev.

So, my conclusion is that if you set the DIP switches to 400 steps per rev (half stepping), with your motors it is actually only 200 steps per rev, and that is the figure that you would need to use in conjunction with your ballscrew pitch to input the proper figure into Mach3. And so on for the other DIP switch settings.

As noted above, this is just conjecture on my part, but I'm relatively confident that it's correct.

Funny, that's what I said earlier.:rolleyes:
http://www.cnczone.com/forums/keling_products/134295-5056d_compatible_3_6_degree.html
Hoss

doorknob
08-16-2011, 04:54 PM
Funny, that's what I said earlier.:rolleyes:
http://www.cnczone.com/forums/keling_products/134295-5056d_compatible_3_6_degree.html
Hoss

Funny, but that's also what I said even earlier:

http://www.cnczone.com/forums/979325-post7.html

GMTA* :)

(*great minds think alike - I could only wish to someday have your level of experience, Hoss)

Fastest1
08-16-2011, 06:26 PM
Thanks to all regardless. I am thinking that even with my confusion on microstepping it must be a BOB to driver issue. I would have thought I would have seen some motion or a squeal or something. I know the PP is good as I can see the pins change on the tester and if I connect it to my Sherline it works fine. I do believe I understand the microstepping concept or question much better now. It is just a division of the steps of the stepper.

Mad Welder
08-24-2011, 12:36 PM
It is just a division of the steps of the stepper.

You seem to have got sorted, but if it's of any benefit to you have a look at this youtube CNC Electronics 8.mp4 - YouTube all you need to do is reconfigure the equation to your own stepper motors 3.6 degree or 100 steps per revolution.