-
General
-
General LinuxCNC Questions
-
NOT SITTING AT ABSOLUTE POSITION AFTER UPGRADE FROM 2.7 to 2.8
NOT SITTING AT ABSOLUTE POSITION AFTER UPGRADE FROM 2.7 to 2.8
Less
More
-
Posts: 179
-
Thank you received: 6
-
-
13 Nov 2018 13:17 #120534
by COlger81
After upgrading to Master from 2.7, my mill does not sit at absolute zero. After homing sequence, each axis sits roughly .0003" to .0005" from absolute machine zero. Prior to upgrade, i did not have this issue. I have gone over my INI and HAL file and can not locate an issue.
Picture of the GUI, HAL, and INI file attached.
Please Log in or Create an account to join the conversation.
Less
More
-
Posts: 179
-
Thank you received: 6
-
-
13 Nov 2018 14:36 #120546
by COlger81
I have checked for mechanical issues such as backlash. This is not a mechanical issue as stated, this issue was not there before i upgraded to Master. Seems like something in software has changed.
Please Log in or Create an account to join the conversation.
Less
More
-
Posts: 24224
-
Thank you received: 4798
-
-
13 Nov 2018 15:36 #120558
by andypugh
Is your GUI set to display commanded or actual position?
(possibly it is now defaulting to actual rather than commanded)
Is this metric or imperial? If metric this might simply be the encoder limit.
Please Log in or Create an account to join the conversation.
Less
More
-
Posts: 179
-
Thank you received: 6
-
-
Less
More
-
Posts: 24224
-
Thank you received: 4798
-
-
13 Nov 2018 15:49 #120563
by andypugh
It may have been showing commanded position before the update?
Three tenths isn't terrible for a mill.
Please Log in or Create an account to join the conversation.
Less
More
-
Posts: 179
-
Thank you received: 6
-
-
13 Nov 2018 15:55 #120566
by COlger81
I was using actual position on 2.7 also. It would sometimes dance around .0001". The mill is capable of .0001" but that aside, if that was the case, adjusting backlash should have an effect on the actual position. Adjusting backlash has zero effect on this issue.
Please Log in or Create an account to join the conversation.
Less
More
-
Posts: 179
-
Thank you received: 6
-
-
Less
More
-
Posts: 24224
-
Thank you received: 4798
-
-
13 Nov 2018 16:17 #120569
by andypugh
I can't remember if anything is different between the PID in 2.8 and 2.7.
Do your PID terms seem familiar?
Did you simply convert the old configs to 2.8, or did you recreate the config?
You could try a bit of I-gain to pull the steady-state error in, but that's not an answer to what might have changed.
Please Log in or Create an account to join the conversation.
Less
More
-
Posts: 179
-
Thank you received: 6
-
-
Less
More
-
Posts: 179
-
Thank you received: 6
-
-
-
General
-
General LinuxCNC Questions
-
NOT SITTING AT ABSOLUTE POSITION AFTER UPGRADE FROM 2.7 to 2.8
Time to create page: 0.238 seconds
