Manually find endstop corrections on a delta?

blt3dp

Just curious how this might be done. My thought was to do something like this.

Use a rod and place it against the linear rail and move the carriage down until it touches the rod.
Do the same thing for all 3 towers.
Set the position, G92 X0 Y0 Z0
?

It's that last part I don't know how to get the machine to measure how much movement it takes to return to the endstops.

Danal

Simple answer: Don't. Auto-calibrate works REALLY well.

dc42

If you built your delta accurately, it should be possible to get the endstops within 1mm height of each other. Then use auto calibration to find the corrections (you can even do this without a Z probe). If that shows that the endstop corrections are larger than you would like, you can adjust the endstop heights and repeat.

Naqaj

@dc42 Can the 3-factor manual Auto Delta Calibration be changed to a 6 factor calibration? If so, where would I find that setting?

dc42

@naqaj said in Manually find endstop corrections on a delta?:

@dc42 Can the 3-factor manual Auto Delta Calibration be changed to a 6 factor calibration? If so, where would I find that setting?

Yes, manual and automatic calibration are exactly the same. The S parameter on the final G30 command in bed.g is the number of calibration factors. Using P0 in the M558 command (meaning no Z probe) is what tells the firmware that you are determining the height errors manually.

blt3dp

@dc42 said in Manually find endstop corrections on a delta?:

If you built your delta accurately, it should be possible to get the endstops within 1mm height of each other. Then use auto calibration to find the corrections (you can even do this without a Z probe). If that shows that the endstop corrections are larger than you would like, you can adjust the endstop heights and repeat.

how would I do this? I though the auto calibration required a z probe.

dc42

@blt3dp, read the wiki page on delta calibration. It includes calibrating without a Z probe.

Danal

@blt3dp said in Manually find endstop corrections on a delta?:

how would I do this? I though the auto calibration required a z probe.

Do read the wiki, but short conceptual answer: If no Z probe is configured, running G29 will cause the web interface to pop open a window that guides you through manually probing each point via clicking z up or down and dragging a piece of paper.

In fact, it is really easier to "just do it" than to read the wiki...