✨ Runtime Homing Feedrate (G28 F)

[vovodroid]

Following to #27344 (comment)

Add G28 F<mm per minute> home speed parameter (axes X/Y only), could be useful for sensorless homing tuning.

[thisiskeithb]

Do you plan to add menu options as well?

[vovodroid]

Well, if I have time.

[vovodroid]

By a way, is it needed for switch homing?

[thisiskeithb]

By a way, is it needed for switch homing?

You can define a homing feedrate in your config and that applies to all homing types, so I'd say yes.

[vovodroid]

I mean that there's no need in such precise tuning for switches, any speed works.

[thisiskeithb]

I mean that there's no need in such precise tuning for switches, any speed works.

It may not need the precise tuning of sensorless homing, but it's still an option that should not be excluded:

Marlin/Marlin/Configuration.h

Line 2305 in 8ac0f14

#define HOMING_FEEDRATE_MM_M { (50*60), (50*60), (4*60) }

[narno2202]

And why not a more global menu to set homing feedrate and in case of sensorless homing capable drivers , homing current, stallguard sensitivity and a test option.

[thinkyhead]

As this is currently structured, it makes more sense for G28 F to set the feedrate only temporarily, until G28 exits, and if a particular axis or set of axes is specified, it would make sense to apply the F value to all of the specified axes, but perhaps with some special cases.

For a more complete implementation of a runtime-configurable homing feedrate, we will need to implement G-code M210 along with the MarlinUI menus that pertain to that. This was discussed in another issue, and we expected to get some implementation, so perhaps now is the best opportunity to follow up on that.

[thinkyhead]

I did my best to apply a temporary homing feedrate with a single 'F' value in G28. Applying this across all specified (or required) axes during a 'G28' makes the override a little sketchy. It must be used very selectively, and only when you're sure you know which axes are actually going to end up homing. If you sent G28 O Z there are cases where this might only home X or Y, and not home Z at all. Some consideration must be given to this logic, or this extra override will need to be removed. Users can just send M210 just before G28 and then save it for later if it's their default preference.