A Axis DRO versus Actual Rotation (resolved)

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RGSparber
Posts: 150
Joined: Sat May 27, 2017 2:12 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: 38D269533454-0111180523
DC3IOB: No
CNC12: Yes
CNC11: No
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Location: Phoenix, AZ
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A Axis DRO versus Actual Rotation (resolved)

Post by RGSparber »

I cannot find where in the user's manual they discuss how to get my A Axis DRO to match the actual rotation of my A axis.

Any suggestions?

Thanks in advance,

Rick
Last edited by RGSparber on Fri Aug 25, 2017 11:20 am, edited 1 time in total.
RGSparber
Posts: 150
Joined: Sat May 27, 2017 2:12 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: 38D269533454-0111180523
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Phoenix, AZ
Contact:

Re: A Axis DRO versus Actual Rotation

Post by RGSparber »

The document seems to only address how to calibrate a linear axis. I did this on my XY and Z axes yesterday plus populated the backlash values. If you look at http://rick.sparber.org/ZSM.pdf page 8 you will see how I calibrate my Z axis. I'm using a stack of precision ground spacers and a finger DTI.

All three linear axes look fine. My problem is with my rotating A axis and its corresponding DRO value.

Rick
diycncscott

Re: A Axis DRO versus Actual Rotation

Post by diycncscott »

The process is identical.

Basically you command a move and measure how it went. Then take the distance displayed on the DRO and divide it by the measured distance. Start at set a part 0 for A and then jog it 360 degrees (of mechanical motion.) Let's say the DRO read 615.1234 and your move was 360 degrees.

Divide 615.1234/360 = 1.708676111.. this gives you a multiplier that you use to adjust your current revs/unit. If your current Revs/unit is set to .25 then 1.708676111 * .25 = .42716902777.... <--- The new value for your revs/unit on A axis. (Keep in mind that changing revs/unit changes your part zero so you will want to re-zero).
RGSparber
Posts: 150
Joined: Sat May 27, 2017 2:12 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: 38D269533454-0111180523
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Phoenix, AZ
Contact:

Re: A Axis DRO versus Actual Rotation

Post by RGSparber »

It all finally got through my thick head. XYZ and A now work correctly.

Thanks to all!

Rick

https://youtu.be/gAalEkMSsoY
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