Too much extruder cooling

number40fan

https://www.duet3d.com/wiki/Tuning_the_heater_temperature_control

Martin_S

Also here: https://betrue3d.dk/duet-wifieth-pid-tuning-hotend/
Great writeup from another user.

stavrosgmtl

thanks everyone

stavrosgmtl

Hi,

Ran

M303 H1 S240 P1

then

M307 H1
Heater 1 model: gain 353.2, time constant 177.5, dead time 4.4, max PWM 1.00, mode: PID

Added this to config.g

M307 H1 A188.4, C121.7, D4.4 S1

Still having problems, did I miss something?

Stav

deckingman

Why did you add those number to M307 in config.g instead of the result of the auto tune?

Dougal1957

@deckingman:

Why did you add those number to M307 in config.g instead of the result of the auto tune?

I Did wonder that as well

stavrosgmtl

oops. Pasted wrong one.

I really added ;

M307 H1 A353.2, C177.5, D4.4 S1

deckingman

OK. That makes more sense.

Are you using config-overide.g by any chance? What I mean is that if you have previously tuned the heater then entered M500, those values will have been stored in config-overide.g so if you now enter the numbers in config.g using M307, they will still be overridden by whatever is in config-override.g.

stavrosgmtl

Sounds extremely possible, checking…

stavrosgmtl

M500 and config-overide.g save the day, now i get what's going on, tune worked pefectly.

Thanks again
Stav

deckingman

Glad you got it fixed. Personally I don't use config-overide.g for exactly the reason that you have discovered. I prefer to just have the one config.g file.