Retraction at end of print job

[keukpa 5]

Hi All,

I'm having some issues with my UM2. The problem is with the printer doing a rather large retraction at the end of the print. I understand 'why' this happens, but is there a way to disable it as it's causing serious issues.

Basically a the end of the print the UM2 does a large retraction and pulls the filament a fair way back, as this cools and when I come to do the next print (say the following day) the printer can't get the filament to get back in the hot end and as such I need to remove it all and manually re-feed it.

Any help would be appreciated.

Regards,

Keukpa

[Labern 762]

You may have to mush moisture in your filament, moisture makes it expand a lot and can cause these jams, also wait for the printer to fully cool before turning it off as the rear fan needs to cool the insulator down.

[Dim3nsioneer 521]

The retraction at the end of print should be undone at the start of the next print:

https://github.com/Ultimaker/Ultimaker2Marlin/blob/aa8589fae63b13e7349d74549dff261d6b3a3511/Marlin/UltiLCD2_menu_print.cpp#L151

However, I think the retraction of 20mm is too much. I have set my firmware to 12mm quite some time ago and had no problem with it; just the opposite, I printed over 1200 hours with the first (glass filled) teflon isolator and could have printed further.

[keukpa 5]

Thanks for the input guys, see my new post:

https://ultimaker.com/en/community/view/17016-its-all-in-the-ptfe-coupler

This has solved ALL my problems!

Cheers,

Keukpa

[jroen 0]

Obviously this is an old post but maybe somebody can help me a bit.

I have the same problem every now and then because the retraction at the end of a print is too much. When I start a new print I first have to take out the bowden tube, cut the filament, put it back together and then move the filament towards the end of the nozzle. When i don't do it like this, the ptfe coulper wears out very rapidly and many many times it gives underextrusion and feedmotor going toctoctoc.

Where and how can I set the retraction at end of a print from 20 to say 4mm? In the firmware's hex file? Can't find the option in the UM2 settings either.