move slowly Z axes to endstop (low switch)

Danal

The F in home files G1 H2 Z5 F6000 (or similar) is the feedrate. Lower that number to move slower. Try cutting it in half, adjust to your taste from there.

chris4

@Danal said in move slowly Z axes to endstop (low switch):

G1 H2 Z5 F6000

G1 H2 Z5 F6000 should change to G1 H2 Z5 F3000 (for example) only in homez.g file?
Thanks.

Danal

Yes. Change it wherever you want the physical behavior of the printer to change.

chris4

@Danal said in move slowly Z axes to endstop (low switch):

Yes. Change it wherever you want the physical behavior of the printer to change.

I am a little confused, have changed to in all home filles, homeall.g, homex.g homez.g, homey.g, but still X axis has the same speed on the way down to endstop. if you want to check my home files, would be grateful for that.

; homeall.g
; called to home all axes
;
; generated by RepRapFirmware Configuration Tool v2.1.8 on Fri Feb 21 2020 13:36:07 GMT+0100 (centraleuropeisk normaltid)
G91                     ; relative positioning
G1 H2 Z5 F6000          ; lift Z relative to current position
G1 H1 X-268 Y-245 F800 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 H2 X5 Y5 F3000       ; go back a few mm
G1 H1 X-268 Y-245 F360  ; move slowly to X and Y axis endstops once more (second pass)
G1 H1 Z-245 F160        ; move Z down stopping at the endstop
G90                     ; absolute positioning
G92 Z0                  ; set Z position to axis minimum (you may want to adjust this)

; Uncomment the following lines to lift Z after probing
;G91                    ; relative positioning
;G1 Z5 F100             ; lift Z relative to current position
;G90                    ; absolute positioning

; homex.g
; called to home the X axis
;
; generated by RepRapFirmware Configuration Tool v2.1.8 on Fri Feb 21 2020 13:36:07 GMT+0100 (centraleuropeisk normaltid)
G91               ; relative positioning
G1 H2 Z5 F6000    ; lift Z relative to current position
G1 H1 X-268 F1800 ; move quickly to X axis endstop and stop there (first pass)
G1 H2 X5 F3000    ; go back a few mm
G1 H1 X-268 F360  ; move slowly to X axis endstop once more (second pass)
G1 H2 Z-5 F160   ; lower Z again
G90               ; absolute positioning

; homey.g
; called to home the Y axis
;
; generated by RepRapFirmware Configuration Tool v2.1.8 on Fri Feb 21 2020 13:36:08 GMT+0100 (centraleuropeisk normaltid)
G91               ; relative positioning
G1 H2 Z5 F6000    ; lift Z relative to current position
G1 H1 Y-245 F1800 ; move quickly to Y axis endstop and stop there (first pass)
G1 H2 Y5 F6000    ; go back a few mm
G1 H1 Y-245 F360  ; move slowly to Y axis endstop once more (second pass)
G1 H2 Z-5 F160   ; lower Z again
G90               ; absolute positioning

; homez.g
; called to home the Z axis
;
; generated by RepRapFirmware Configuration Tool v2.1.8 on Fri Feb 21 2020 13:36:08 GMT+0100 (centraleuropeisk normaltid)
G91               ; relative positioning
G1 H2 Z5 F3000    ; lift Z relative to current position
G1 H1 Z-245 F160 ; move Z down until the endstop is triggered
G92 Z0            ; set Z position to axis minimum (you may want to adjust this)

; Uncomment the following lines to lift Z after probing
;G91              ; relative positioning
;G1 Z5 F100       ; lift Z relative to current position
;G90              ; absolute positioning

Regards Christian

Phaedrux

It's the F values that dictate the speed of movement (limited to the max speed set in config.g with M203).

So if you want a move to be faster you'd have to change it for each move.

chris4

@chris4 said in move slowly Z axes to endstop (low switch):

change the speed of Z axis on the way to endstop (low switch) to a slow speed last cm, to endstop. The same slow speed, as on the x and y axis. I have this config.g

I want to change the speed of Z axis on the way to endstop (low switch) to a slow speed last cm, to endstop. The same slow speed, as on the x and y axis. I have this config.g

Phaedrux

@chris4 said in move slowly Z axes to endstop (low switch):

G91 ; relative positioning
G1 H2 Z5 F3000 ; lift Z relative to current position
G1 H1 Z-245 F160 ; move Z down until the endstop is triggered
G92 Z0 ; set Z position to axis minimum (you may want to adjust this)

G91               ; relative positioning
G1 H2 Z5 F3000    ; lift Z relative to current position
G1 H1 Z-245 F3000 ; move Z down until the endstop is triggered
G1 Z5 ; back off 5mm
G1 H1 Z-25 F360 ; move back to endstop again slowly
G92 Z0            ; set Z position to axis minimum (you may want to adjust this)

Something like this, similar to how you have x?

EDIT: Fixed G1 H1 Z5 to be G1 Z5.

chris4

Thanks, I'll try.

Phaedrux

@chris4 I had an error in there. I had H1 Z5 ; back off 5mm but you'd of course need G1 H1 Z5 ; back off 5mm

Danal

@chris4 said in move slowly Z axes to endstop (low switch):

I want to change the speed of Z axis on the way to endstop (low switch) to a slow speed last cm, to endstop. The same slow speed, as on the x and y axis. I have this config.g

Prior to hitting an endstop (i.e. 'homing') the machine does not know where it is. Therefore, it cannot run at one speed and the switch to another speed for the last cm, because it does not know where the last cm starts.

It IS possible to run two homing switches, and slow down after the first one is passed... but even this is not a universal solution... what if the machine is "in between" the switches when it powers up? To solve this, the "go fast until here" switch MUST remain triggered while the machine is still moving toward the "final" endstop.

So... an optical endstop, with a "blade" or "gate" on the moving part of the machine such that it triggers 1cm from final, and stays triggered, plus a final endstop switch. That is one potential solution. The same thing can be accomplished via inductive switches and long metal plates. If you are willing to set something like this up mechanically, a "fast then slow" can be configured to work consistently.

Most people aren't willing to do this. A single switch with a medium speed approach, a back off, and a slow final, that works so well it has become a de-facto standard.

dc42

@Phaedrux said in move slowly Z axes to endstop (low switch):

@chris4 I had an error in there. I had H1 Z5 ; back off 5mm but you'd of course need G1 H1 Z5 ; back off 5mm

And H2 in that command, not H1.

Phaedrux

@dc42 ah yes. I think I intended to have just g1 z5 since it would be homed, but then corrected my typo with another error.

Danal

@Phaedrux said in move slowly Z axes to endstop (low switch):

corrected my typo with another error.

Wow, I've NEVER done that!!!