Filament Diameter Sensors and RRF?

[CNCModeller]

Hi All,
I've been looking into ways of making the use of cheap filament more effective for prototyping large PLA prints.

One of the issues I have with surface quality seems to be filament diameter. I don't have issues with clogging, probably because I generally print with larger 0.6mm nozzles.

I've come across this filament diameter sensor from Thomas Sanladerer here:-

https://youtu.be/RYgdLPe_T0c

https://www.prusaprinters.org//prints/57154-infidel-inline-filament-diameter-estimator-lowcost

After a search through the gcode directory it doesn't seem its directly supported, I guess I could periodically update the filament diameter for the extruder but I'm not sure how to do that on a regular basis either by filament extrusion length or time. But id still need to read in a voltage.

I guess I could create an arduino that reads the sensor using the code in TS' project and then sends a gcode command via the paneldue interface (as per the CNC pendant) that updates the filament diameter if it varies more than a specified margin.

I am however unsure if I need to offset that information for sensor to extruder distance as I'm not sure how rapidly the filament diameter varies. And if I did need to offset it I'm not sure how I'd achieve it, perhaps a distance measurement via an encoder within the diameter sensor... now that's getting really complicated!

Anyway, if anyone else has had any experience of using diameter sensors and would like to share it'd be good to hear from you!

As always any constructive thoughts would be much appreciated!

All the Best
Barry M

[T3P3Tony]

@cncmodeller thanks, we are discussing how to work with filament width sensors sensibility.