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Author Topic: Help needed  (Read 5183 times)

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Offline Hood

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Re: Help needed
« Reply #10 on: December 18, 2010, 05:09:53 PM »
I think 25KHz should be fast enough for you even at 1/8 microstepping as that would mean you could achieve (25,000/16,000) x 60 = 93.75IPM.
If you find your motors are fine at that max Velocity and you want more then you can increase the Kernel to 35KHz and that would allow a theoretical max Vel of (35,000/16,000) x 60 = 131.25IPM

45KHz would  allow a max of 168.75
etc etc
  45KHZ may be the max your computer is happy at, some people can easily run 60KHz or even 100KHz but others can get unstable at anything over 25KHz.
Hood
Re: Help needed
« Reply #11 on: December 18, 2010, 06:31:35 PM »
Thanks again -

With 1 FULL STEP and all the other stuff mentioned before - I am usually right under an 1/8" short almost every time. Frustrating

Offline Hood

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Re: Help needed
« Reply #12 on: December 18, 2010, 06:45:52 PM »
Increase the pulse width and Dir Prechange  to  5 and see if that helps, they are on Motor Tuning page.

One thing though, is it always 1/8 inch off, for example if you command a 1 inch move does it go 7/8 and if you command a 2 inch move does it move 17/8 or does it move 13/4?
Hood
Re: Help needed
« Reply #13 on: December 18, 2010, 07:21:09 PM »
Man this is so much fun.... :)
I did not change anything....
Anyway - I do not know if it is my Y or X axis because I did not mark the material. I cut a 2"x2" square and it ended up being 2" exactly on one side and 1.98" on the other side.

That is pretty close. :)

Is it worth trying any further or do you think that is close as it gets?

Thanks -
Keith

Offline Hood

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Re: Help needed
« Reply #14 on: December 18, 2010, 07:35:31 PM »
Depends on the machine, for a metal working machine that would be a massive error but on a wood working machine it may not matter.

Could it be backlash on the axis that is coming out small?
How to test is move the axis in a positive direction by jogging then zero the DRO for that axis now move via the MDI line by typing G0X1 (or G0Y1) and see if it moves the full 1 inch. If it does then command a G0X0 and see if it is off. If it is then it is definitely backlash.

How you will actually measure the distance travelled depends on what you have available, dial gauge is good. If however you dont have one  you could move positive, zero the axis and then lower the Z and bore a hole in some material then raise Z and command the 1 inch move then   command the move to back to zero and lower the Z again, you will see if its going in the same hole or if its off a bit.
Hood
Re: Help needed
« Reply #15 on: December 18, 2010, 07:36:39 PM »
Just did a couple of wooden gears.   :)
Re: Help needed
« Reply #16 on: December 18, 2010, 07:38:24 PM »
Thanks Hood!! Will try those steps.

I appreciate all the help.

Offline Hood

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Re: Help needed
« Reply #17 on: December 18, 2010, 07:38:43 PM »
Looks good :)
Hood