Jogging and DRO

[donaldo]

Using Mill 4 Axis 3.46.1

If I jog on any axis in step mode, the increment eventually gets off except on the .1000 resolution. It works the same on X, Y, and Z and it is the same from the jog page or from the Pendant.

.0005 resolution it goes; .005, .0010, .0015, .0020, .0025, .0030, .0034, .0039 and then at .0094, .0098

.0010 resolution it goes; .0010, .0020. .0030, .0039

.0100 resolution it goes; .0100, .0201, .0301, .0402

Is this a "feature" of the software or something going on with my new setup?

 

[cncnutz]

Hi donaldo

It is neither a feature nor an error but simple mathematics. You are seeing 2 different effects.
When you jog each step is an incremental movement. The axis moves as close as it can to the required distance. The amount it moves will depend on axis resolution.
The slight error you see in the .0010 4th move is due to rounding. The display is not large enough to display the actual position past 4 decimal places but Masso keeps track on the remaining digits and eventually it will show up on the display.

Cheers
Peter

 

[donaldo]

Hi Peter,

This makes sense if you are measuring the actual machine movement, but does not for what is displayed on the DRO.

If you hit the jog button (Y+) and you have .001 selected for the resolution, then each click should tell the DRO to move exactly .0010000000 or how ever many zero's . There should not be any rounding involved. It still seems like a software issue to me.

Thank you,

Don

 

[cncnutz]

The DRO needs to display actual position or movement and not desired movement otherwise position will get lost very quickly.

For example my X & Y axis smallest physical movement is 0.0013mm. To move 0.001 the best the machine can do is take 1 step and move 0.0013. If I take 10 steps I will have moved 0.013mm and not 0.01mm.

If I ask it to move 0.01 then I can take 7 steps and 0.0091 or 8 steps and move 0.00104 but I cannot move exactly 0.00100000. The DRO must show actual position.

Hope this makes sense.

Cheers Peter