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Author Topic: step and direction spindle control  (Read 6737 times)

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Re: step and direction spindle control
« Reply #10 on: February 16, 2010, 08:02:44 PM »
how do I attach it.

I don't find an attach file choice

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Re: step and direction spindle control
« Reply #11 on: February 16, 2010, 08:05:26 PM »
You will find an additional options button on the reply page, just click that then choose and browse to your xml. You may have to rename your xml first though as the forum will only accept a file name once and if you have a standard profile it will have been posted before, so copy it to your desktop first and rename to something like OBCues.

Hood
Re: step and direction spindle control
« Reply #12 on: February 16, 2010, 08:08:02 PM »
I bet that was it. Lets see how this works


Royce

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Re: step and direction spindle control
« Reply #13 on: February 16, 2010, 08:26:42 PM »
Ok a few things,
First is set the kernel speed to 25KHz, it can affect feedrate readings when using the SS, actual feedrate will  be correct, just displays wrong.

Next set the E-Stop up to a port and set it active low if you dont have one, that way you wont get the annoying message.

You seem to be set to pulley 4 according to that xml so set to pulley 1 or best bet is set all pulleys to the max speed you will be doing on the spindle.

Your acceleration seems  high for a stepper spindle and is a likely cause of you stalling when you command a high speed, I would try 10 for a start, remember its revs/s/s as opposed to a normal axis being units /s/s

Go into the SS plugin and set the pulse width to 1.5, with it set at 5 you will likely saturate the step signal as there is no divider on the spindle signal like there are on the axis.

Hopefully these will sort you out, if not I will check in the morning, its 1:30am here so I better get some sleep :D

Hood
Re: step and direction spindle control
« Reply #14 on: February 16, 2010, 09:03:42 PM »
Hood,

Thanks for the help.

I will try those things. It's 8 here, and I am home now. I will try them in the morning and see what happens.

Thanks again

Royce
Re: step and direction spindle control
« Reply #15 on: February 17, 2010, 04:44:03 PM »
Hood,

Thanks for your help! I have it working right now.

I set the Kernel back to 25khrz and matched my pulley speed and velocity setting. Art gave me a good explanation on the yahoo forum as to how Mach calculates the spindle speed. It's interesting! Here it is:

Royce:
>
> The velocity is in mm or inches per minute. In the case of the spindle
> that would be 540 would be the correct setting for that 1600 step value.
> This works out to (1600 * 540) /60 steps per second. Thats 14400 steps
> per second, or 9 revs per second.
>
> The reason the speed changes when you affect the slider is that some
> of the math for the spindle uses a variable called SpindlePerSecond,
> which is
> scaled from the top speed youve set. SO if you change the slider you
> do affect the entire range of the spindle. In other words the spindle
> is set as a maximum value. ( in your case 540RPM ), so when you select
> S270, the system actually just grabs the max speed and gets 50% of
> that to calcuate the
> actual commanded speed. SO the slider always has an effect on the
> actual speed output. It should always be accurate in terms of the end
> speed,
> but you may have to restart the software so the SpindlePer is
> recalculated, somethign like that may be going on..
>
> So use 540 as the correct number, but if you reset the slider any try
> restarting the software after saving to see if its still working properly.
>
> Thanks,
> Art

I should note that these settings only work, with the Smooth Stepper, when the pulley speed and the velocity settings are the same! My other machines don't seem to be sensitive to this, but this one is.

I even jumped everything up to 1000 on both the velocity and the pulley speed and my speeds are correct.

It is very important to restart Mach any time you change a setting with the spindle. As Art stated above, it has to recalculate the SpindlePer number.


Thanks for everyone's help!

Royce Bunnell
www.obcues.com

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Re: step and direction spindle control
« Reply #16 on: February 17, 2010, 05:13:40 PM »
Yes it is only the SmoothStepper that looks at the spindle pulleys max speed for this, not sure why Greg did that but it took a while to work out why I was having to set weird numbers to get things correct.

As for Arts explanation, that will be for the parallel port and I think the SS probably does it itself rather than Mach, however it is likely to be very similar.
Hood
Re: step and direction spindle control
« Reply #17 on: February 17, 2010, 05:35:12 PM »
Thanks!

The other thing that was a big problem is my xylotex board must have a short.

I have it jumper'd for micro step, 1/8th, but it must be shorted because I have to program 400 steps per unit instead of 1600 to make it work right.

go figure!

With it all set right, I was actually able to get 1000 rpm out of my little Pac Sci stepper I am using for the spindle. I have never been able to get over 650 or so before. I also had intermittent issues with positioning, and those are gone now. I am assuming they were parallel port issues as I don't think it was missing steps due to load or acceleration or anything like that.

I have 4 machines total, one 4 spindle 2 axis that uses 4 table saw blades to do the cutting. Boy can it make some sawdust! 2 smaller single spindle machines using routers to cut with and one 2 spindle that uses routers. The 2 spindle is vertical and is basically in a closet on wheels. I can roll it to where I need it, hook up dust collection and power and cut away!

Thanks again for your help.

Royce Bunnell
www.obcues.com

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Re: step and direction spindle control
« Reply #18 on: February 17, 2010, 05:46:38 PM »
It was likely your pulse from the parallel port was not great, thats where a smoothstepper will be of great benefit as it produces a nice clean pulse :)

Hood