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Author Topic: DRO readouts for Home to maximum limit of axes  (Read 1765 times)

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DRO readouts for Home to maximum limit of axes
« on: June 05, 2013, 11:33:37 AM »
Hi
When jogging from home to the full extent of my table ( home to limit switch) the DRO's give different readings as to what the size of the table is.
I have M3 set to mm and the size of the table is approx 1500 x 1500mm with the z travel being approx 150mm. The working area is 1200 x 1200 x 100mm.
The DRO's read the following at the limit switches.
X  388.2416
Y  398.0899
Z  -131.0635
They all travelled from home.... i.e. 0
 

Offline Hood

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Re: DRO readouts for Home to maximum limit of axes
« Reply #1 on: June 05, 2013, 11:35:21 AM »
Sounds like  have the wrong steps per unit set.
Hood
Re: DRO readouts for Home to maximum limit of axes
« Reply #2 on: June 05, 2013, 11:40:16 AM »
Hi Hood
I thought as much. I had originally used the xcel calculator and manual calculations when originally setting up a few months ago.
I will recheck my calcs and see where I went wrong
Regards
Gary
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Re: DRO readouts for Home to maximum limit of axes
« Reply #3 on: June 06, 2013, 07:16:04 AM »
Hi
it would be appreciated if some kind soul would check my calculations. Formula are one of my weak points.
My set up is as follows:
The dreaded TB6560AHQ blue board set to: 75% current; fast decay; 1/8 micro steps.
Motors: 1.8 deg Steppers.
X & Y Axes: Rack and pinion:- module 1.5, pitch 4.71; 18 tooth pinion; 60 tooth pulley on pinion; 20 tooth pulley on motor.
Z Axis: direct drive:- 1/2" - 10 -  5 start acme screw.
All my work will be done in millimeters and have converted the motor revs/unit to metric [i.e. 2revs/(inch or 25.4mm) =0.0787401revs/mm].
According to my calc the M3 steps/unit are:
X & Y: 400
Z: 126
Some how my fuzzed out brain managed to get the same figures using the calculator, but would prefer someone to confirm I was on right or wrong track.
Tks
G