I am using an ssr to control a linear compressor for a berd-air part cooling system.

Standard pwm signal did not vary the compressor output (it only operated at full) so I added a full bridge rectifier after the ssr so now one dc pulse = one pulse of the compressor. I use the M950 Q command to vary the frequency of my compressor and then adjust pwm duty cycle to get the pump running smoothly anywhere from 1-60hz.
The problem is that it takes a lot of gcode post processing to make my part cooling fan work.
The reason I want to use this compressor is so i can use one "fan" on a tool changing matching with a standard V6 hot end and with a super volcano hot end, even laser air assist some day.

I think people laser cutting or even cnc routers could use these compressors if fan outputs could be switched to pulse frequency modulation with some sort of duty cycle

@zapta Thanks alot. that did the trick.

the relay i'm using is here amazon relay

@fcwilt I have the buildtak system. Just have to try it

@phaedrux I might try G29 S1 but I have a removable magnetic bed. so if I have to take it off I will probably need to re-probe.

@phaedrux I took out that m376 and now it's working thank you so much!

Its not great but it is actually usable over my whole bed now.

Things are a bit temporary right now as I plan on changing most of this printer. as soon as it can print its own replacement parts I will rebuild it and maybe double my probing points.
I just don't want to wait that long for it to probe....

@phaedrux
my bed is a little warped, needs some work but nothing bed compensation should handle it for now.

Number of points: 100
Probe area: 2397.1 cm²
Maximum deviations: -0.270 / 0.581 mm
Mean error: 0.252 mm
RMS error: 0.184 mm

@phaedrux said in mesh bed compensation not compensating:

M376 H10

It set at 11.2 mm to make a good section of my bed useable.

I will take out that M376 and see if that helps.

thank you

@fcwilt
The machine homes and probes without a hot end attached then when it starts printing it picks up a tool from the rack and uses that tools offsets.

The nozzle I currently have configured hangs about 11mm below the switch when mounted. So T1 has a -11 mm z offset.

I believe that the e3d tool changer uses a similar method

@fcwilt
And I should be the one thanking you.

I'm at a loss with this machine. Hopefully someone here can figure out how to make it dance for me

@fcwilt
It's just a little micro switch.

This is a tool changing machine so I gave the probe 0 offset and apply an individual offset to each tool.

It's not all configured yet. I just have one nozzle printing now.

@fcwilt look at that. I learnt something new today

; homeall.g
; called to home all axes
;
; generated by RepRapFirmware Configuration Tool v3.1.4 on Thu Oct 29 2020 12:06:14 GMT-0600 (Central Standard Time)



G91                    ; relative positioning
G1 H2 Z5 F6000         ; lift Z relative to current position
G1 H1 X-593 Y616 F10000 ; move quickly to X or Y endstop and stop there (first pass)
G1 H1 X-593            ; home X axis
G1 H1 Y616             ; home Y axis
G1 X5 Y-5 F10000        ; go back a few mm
G1 H1 X-593 F1000      ; move slowly to X axis endstop once more (second pass)
G1 H1 Y616             ; then move slowly to Y axis endstop
G90                    ; absolute positioning
G1 X5 Y5 F12000       ; go to first bed probe point and home Z
G30                    ; home Z by probing the bed

; homex.g
; called to home the X axis
;
; generated by RepRapFirmware Configuration Tool v3.1.4 on Thu Oct 29 2020 18:46:36 GMT-0600 (Central Standard Time)
G91               ; relative positioning
G1 H2 Z5 F6000    ; lift Z relative to current position
G1 H1 X-593 F10000 ; move quickly to X axis endstop and stop there (first pass)
G1 X5 F10000       ; go back a few mm
G1 H1 X-593 F1000 ; move slowly to X axis endstop once more (second pass)
G1 H2 Z-5 F6000   ; lower Z again
G90               ; absolute positioning

; homey.g
; called to home the Y axis
;
; generated by RepRapFirmware Configuration Tool v3.1.4 on Thu Oct 29 2020 18:46:36 GMT-0600 (Central Standard Time)
G91              ; relative positioning
G1 H2 Z5 F6000   ; lift Z relative to current position
G1 H1 Y616 F10000 ; move quickly to Y axis endstop and stop there (first pass)
G1 Y-5 F10000      ; go back a few mm
G1 H1 Y616 F1000  ; move slowly to Y axis endstop once more (second pass)
G1 H2 Z-5 F6000  ; lower Z again
G90              ; absolute positioning

; homez.g
; called to home the Z axis
;
; generated by RepRapFirmware Configuration Tool v3.1.4 on Wed Oct 28 2020 15:43:06 GMT-0600 (Central Standard Time)


G91              ; relative positioning
G1 H2 Z5 F6000   ; lift Z relative to current position
G90              ; absolute positioning
G1 X5 Y5 F12000 ; go to first probe point
G30              ; home Z by probing the bed

here is a sample of my start gcode

;Generated with Cura_SteamEngine 4.8.0
T1
M190 S70
M104 S240
M109 S240
M82 ;absolute extrusion mode
G28 ;Home
G29 S0 ; mesh bed compinsation
G1 Z15.0 F6000 ;Move the platform down 15mm
;Prime the extruder
G92 E0
G1 F200 E3
G92 E0
M141 S0
M83 ;relative extrusion mode
G1 F1500 E-0.5
;LAYER_COUNT:89
;LAYER:-7
M107
G0 F18000 X69.373 Y337.319 Z0.36
;TYPE:SUPPORT-INTERFACE
G1 F1500 E0.5
G3 X98.183 Y344.153 I6.806 J35.452 E5.47936 F675