Hello Guest it is March 29, 2024, 01:24:00 AM

Author Topic: Jogging A axis at .0001 problem  (Read 8257 times)

0 Members and 1 Guest are viewing this topic.

Offline Leed3

*
  •  162 162
    • View Profile
Jogging A axis at .0001 problem
« on: January 21, 2007, 02:15:54 AM »
Hi,
I am using version 2.00.037 and have noticed the following problem (also existed in previous version). If I set Jog Mode to Step and increment to .001 jogging works fine on X,Y,Z and A axis. If I set it to .0001 then X,Y and Z work fine but A does not. Sometimes it will move the motor and DRO 1 or 2 increments and then die and sometimes it just will not work at all. In General Config A-Axis is Angular is checked, Rot 360 rollover is not checked. Kernel speed is set for 25000. Does anyone have any suggestions on how to get the A Axis to work properly? It is feeding a stepper on a rotary table. Also, does anyone know the format code (for Screen 4) to get the A Axis DRO to display angle degrees instead of .*********X? I think that I just need to move the decimal over 2 places.

Thanks :)

Offline Chip

*
  • *
  •  2,055 2,055
  • Gainesville Florida USA
    • View Profile
Re: Jogging A axis at .0001 problem
« Reply #1 on: January 21, 2007, 08:19:04 PM »
Hi, Leed

In Config tool path select A Rotations Enabled, then OK for Deg. 4th Axis.

As far as the .0001, Art or someone stated that if your steps per aren't 10,000 or more it wont step .0001.

Hope this Helps, Chip

Offline Leed3

*
  •  162 162
    • View Profile
Re: Jogging A axis at .0001 problem
« Reply #2 on: January 22, 2007, 02:24:56 AM »
Yes it helps.  My steps are set to 16,000 (Sherline 1/2 step) = 8,000 so I can't do .0001. I would need to set it at 20,000.  The A Axis DRO needs some more work on it. I'll see what I can figure out.

Thanks
Lee

Offline Chip

*
  • *
  •  2,055 2,055
  • Gainesville Florida USA
    • View Profile
Re: Jogging A axis at .0001 problem
« Reply #3 on: January 22, 2007, 02:02:16 PM »
Hi, Lee

In screen4, double click on 4 th axis dro, brings up dro control the text %+.4f controls the  window, the 4 is for 4 zeros to the right.

Haven't been able to find Doc's that exp. it's exact use though.

If your trying to calibrate in deg's then step's need to be number required to move 1 degree,  in motor tunning, steps per.

Thanks, Chip

Offline Leed3

*
  •  162 162
    • View Profile
Re: Jogging A axis at .0001 problem
« Reply #4 on: January 22, 2007, 04:40:20 PM »
Hi Chip,

Thanks. That helps. I thought it was just me that couldn't find the documentation on formatting. I'll work on it later today.

Regards
Lee

Offline Chip

*
  • *
  •  2,055 2,055
  • Gainesville Florida USA
    • View Profile
Re: Jogging A axis at .0001 problem
« Reply #5 on: January 22, 2007, 07:49:20 PM »
Hi, Lee

I forgot to mention one more item, if you set the steps per to 1 deg. value, You will meed about 2500 vel. and 500 accl. values in motor

tunning.

Well anyway that's what it takes for my sheline table to run fast enough, set to miss steps then back off some for both settings.

Also set dia for A axis in settings page.

Thanks, Chip

Offline Leed3

*
  •  162 162
    • View Profile
Re: Jogging A axis at .0001 problem
« Reply #6 on: January 22, 2007, 10:02:22 PM »
Hi Chip,
Would you please give me an example of setting the A Axis Dia? Is it supposed to be set to the Dia of the rotary table (4")? Also, are you using the Sherline steppers and Sherline controller? I have the steps set to 16000 for X Y and Z and it works fine. I also have it set for 16000 for A. The actual correct number should be 160 but that causes the stepper to run super slow and make noise. I played with Vel and Acc but it didn't seem to make any difference. I can try the numbers you suggested in the morning.

Thanks
Lee

Offline Chaoticone

*
  • *
  •  5,624 5,624
  • Precision Chaos
    • View Profile
Re: Jogging A axis at .0001 problem
« Reply #7 on: January 22, 2007, 10:14:46 PM »
Hey Lee,
    The a axis diam. should be the diameter of your part I think. What is the gearing of your set up? 90-1?


Brett
« Last Edit: January 22, 2007, 10:16:50 PM by Chaoticone »
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!

Offline Leed3

*
  •  162 162
    • View Profile
Re: Jogging A axis at .0001 problem
« Reply #8 on: January 22, 2007, 10:33:29 PM »
Hi,
When you say gearing I am not sure what you mean unless you are refering to the worm gear. The rotary table is a Sherline NC ready Rotary Table  8730 with 72 tooth worm gear. Here is Sherlines comments:

The table is 2" high and 4" (100mm) in diameter. The main components have been machined from solid bar stock steel, and the complete unit weighs seven pounds. The table has been engraved with a laser, giving sharp and precise lines every 5°, numbered every 15°. These lines are calibrated with the 72-tooth worm gear that is driven by the handwheel. The handwheel is divided into 50 parts, making each line on the handwheel 1/10°. This allows a circle to be divided into 3600 increments without interpolation. Seventy-two revolutions of the handwheel rotate the table one revolution.

Translated that means a 360 degree turn of the stepper (1.8 degrees motor) moves the table 5 degrees.

That is for the manual table. The only difference on the CNC, is that a double shaft stepper is put on and the handwheel in then put on the back of the stepper.
It is being driven by an 8760 controller box. The specs are here http://www.sherline.com/8760pg.htm

Hopefully that answers your question.

Regards Lee

Offline Chaoticone

*
  • *
  •  5,624 5,624
  • Precision Chaos
    • View Profile
Re: Jogging A axis at .0001 problem
« Reply #9 on: January 23, 2007, 07:01:43 AM »
I come up with 80 steps per degree, or 28,800 per revolution. I think if you set your steps per to 80, your dro will be reading in degrees. This would give you a resolution of .01 degrees. Can you set your steps per at 80 and try it? I don't have a rotary table set up yet.

Brett
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!