Messages

1401

General Mach Discussion / Re: Power Supply Unit

« on: January 11, 2011, 05:39:12 AM »

In the exact words the manufacturer (Keling) said: "You can use the power supply from 24-72VDC"

This appears to be at odds to what you've said at the beginning of your post where you stated 42V max. Are you mixing up max recommended motor V with max driver V. (The motors are Keling - not the drivers).

Certainly if the drivers are these http://www.probotix.com/stepper_motor_drivers/ProboStep (which are the only unipolar drives I can see at Probotix) then the max V is 44V.

From your link the (unipolar) motor inductance is 2.2mh, therefore your "ideal" voltage for "max" speed & torque is 32 * sqrt 2.2 = 47.4636704 Vdc. BUT this is over the 44V limit of your drives. You said your supplier recommended limiting to 42V - a tad below the limit of 44V.

So 42Vdc gives a transformer secondary of 42/1.414 = 29.7029703VAC.

Generally (in the UK anyway) transformer secondarys come in 12, 15, 18, 22, 25, 30... VAC so your nearest fit is 25VAC which will give you 35.35Vdc. This as has been stated earlier is not the "ideal" for your motors but it's the best you can do with your drivers.

Unless of course I've cocked up somewhere  

Ian

1402

General Mach Discussion / Re: Y Axis Issues

« on: January 08, 2011, 06:07:01 AM »

If home is in the lower left, the tool will be in the way, and I'll have to always jog the cutter out of the way to access the work area.

Just home top left and set home to be X0,Y100 (or whatever). i.e. whilst home is perhaps more commonly set to be X0,Y0 - it doesn't have to be, it can be whatever you like.

Cheers

Ian

1403

General Mach Discussion / Re: Help ! "Radial Cut with Zdepth" toolpath from mastercam makes Skip steps ??

« on: January 05, 2011, 07:57:33 AM »

I'd just add that you have your Y and Z step signals set active high. This is wrong for geckodrives which all step on the falling edge. There is also no need to set pulse widths to 5. The default of 0 is correct for geckos. (actually these values are ADDITIONS to the default pulse widths which are around 1 to 2 us so you actually have pulse widths of around 6 to 7 us. This in conjunction with your 100KHz kernel (10us period) is not doing the geckos any favours.

Ian

1404

General Mach Discussion / Re: Help ! "Radial Cut with Zdepth" toolpath from mastercam makes Skip steps ??

« on: January 04, 2011, 09:08:37 AM »

I use step motor drive from gecko

ergo full, half, 5 or 10 microstepping depending on which drive.

I use Ballscrew with 5 mm lead on X and Y.
...
I use step motor with NO gear ratio nor belt reduction, it's a direct drive from motor to ballscrew.

XY steps per 157.48...

Am I missing something here?

1405

General Mach Discussion / Re: xml

« on: January 03, 2011, 07:27:57 AM »

well certainly the xml fails w3c validation but that doesn't neccessarily mean anything. I've seen software that works fine on broken xml simply because it's written to do so. The point is that even if the xml was valid, that says nothing about the validity of the content (the microcontroller flash code).

Ian

1406

General Mach Discussion / Re: Plasma tube cutting

« on: December 24, 2010, 09:56:27 AM »

yep - just read up a little on maxcl and as you say it appears to use pin assignments of it's own and ignores whatever is set in ports n pins. Tried to confirm this with parmon and it looks correct. So although swapaxis still works it's not having the desired effect. sorry for the sidetrack.

Ian

1407

General Mach Discussion / Re: Plasma tube cutting

« on: December 24, 2010, 09:23:45 AM »

Haven't really read all the thread properly so forgive me if I'm out of line. swapAxis is a bit quirky and there's a couple of things to bear in mind when using it.

You can only call it once. That is you must then call resetAxisSwap before calling it again.
When you call swapAxis you'll see the change in step/dir in ports n pins.
motor settings do not follow the swap. Just the step/dir pins.

I have no idea what maxCL mode is but I just ticked it and tried a swapAxis and it worked for me V3.042.040.

Ian

1408

General Mach Discussion / Re: losing steps

« on: December 19, 2010, 04:18:20 AM »

When I checed my zero in X, it showed minus .060 and shoud have showed zero.

OK but it's not just where you ARE (X-0.06), it depends on where you've COME from.
If you'd come from (say) X1 and commanded X0 and it's at X-0.06 then that would be 480 ADDED steps.
But
If you'd come from (say) X-1 and commanded X0 and it's at X-0.06 then that would be 480 LOST steps.

1409

General Mach Discussion / Re: losing steps

« on: December 18, 2010, 06:27:15 AM »

Is there any way to completely disable the "advanced Digital Sync Lock Servo (DSLS) control technology."? because I'm thinking this might be causing your problems. Certainly your 0.06 inch out of pos is 480 steps out if my maths is correct - which if nothing else says your "advanced Digital Sync Lock Servo (DSLS) control technology" is as much use as a chocolate tea pot. BTW is this 480 steps missed or added? - because if it's added, then it's definitely the DSLS that's the problem.

Also (again) if my maths is correct then I make your "High power electronic chopper drive amplifier" (goodness - are these suppliers over egging their pudding or what?) half step drives - so I'm wondering if Sherline mode might be worth a try - but others will know more about this than me.

Cheers

Ian

1410

VB and the development of wizards / Re: Jog button in a script?

« on: December 17, 2010, 05:41:44 AM »

OK - fair enough - but doesn't it also continually execute whatever code you preceed the doOEMButton call with?