calibration of pulse filament sensor

[Tinchus]

Hello. Im about to have an ecoder as a filament sensor. Im setting it up as a pulse sensor. 1 of the paramether in the configuration is the L for mm / pulse
Question is: I think the sensor is well conected, I aleady issued a M591 D0 P7 C"io2.in" S1 L0.5, I can see the sensor declared as "OK" in the sensor list of the object model page. How can I see the pulses the sensor is generating so I can tune the L parameter? My idea is: extrude 1 mm, see how many pulses that generated and from there I get the L value.

Thanks in advance

[jay_s_uk]

@tinchus they only work during a print, which means you can tune during a print.
What you could do, is rather than set it up as an encoder right away, set it up a normal input and then, using a macro, extrude a set amount of material and count the pulses. Then, just divide the amount extruded by the number of pulses.
That'll give you a good idea of the value to then input into the filament monitor command

[dc42]

@tinchus a simple way to calibrate a filament monitor is to set up and print a GCode file that does one long move that includes both extrusion and X or Y movement. For example, if you home the printer, preheat the extruder and select the tool manually before running it, then it can contain just these commands:

G1 X0 F6000
G1 X100 E100 F100

[Tinchus]

@jay_s_uk Exactly that was my idea but the reyou have my question: how do I count the pulses. Where can I see the pulses?

[jay_s_uk]

@tinchus I configure the filament sensor as a trigger using M581. Every time that's called it increments a global variable by 1. That global variable can be read by using the object model or you can do the calc in a macro

[Tinchus]

@jay_s_uk But this trigger method is able to measure this? the wheen of this encoder has 100 holes, is pretty precise. Each trigger will happen like 2 or 3 every mm of filament i guess, that could be like a trigger being triggered 2 o 3 times a second

[jay_s_uk]

@tinchus don't extrude too fast. My filament sensor triggers every 1.37mm of filament extruded

[Tinchus]

@dc42 Thanks for the tip. Ok, will print a gcode of a single line in X or Y direction, a long move at slow speed I guess will be the best?

Just to learn: this data the electronics gathers from this print, is saved somewhere? I mean, what will happen once I turn off the electronics, all the data will be saved or lost and calibration will be needed to be done again?

[Tinchus]

@jay_s_uk I think this will be the final question: I have made the macro and measure a value of 174 pulses for 50mm of extrusion. That gives me a number of 0.29 mm / pulse. So my command now it is like this:

M591 D0 P7 C"io4.in" L3.46 S1 R80:120 E2

In order to learn: above I was told that the monitoring will auto calibrate. This calibration data will modify my initial calculated number of 0.29/mm?
Can I see this data in order to fine tune my command or should I let that calibration "contonue by itself"?

Because using the line above, it gives me always an error while printing "too much movement, even putting a L valuue of R60:300

Only if O used a value of L0.5 (just a number) the printing can continue.

[jay_s_uk]

@Tinchus I'm not sure its auto calibrating as such. just keep an eye on the output from M591 D0 every now and again. The L value shouldn't need to be changed and it should just be the R value