Extruder is skipping steps on purge line
Hi All,
I am having a weird issue with my MK2.5 I have just finished to build. Every time the extruder is doing the first purge line I hear it skipping steps
Things I have checked :
What am I missing?
Thank you for your help 😉
Re: Extruder is skipping steps on purge line
I think the problem is , a lot of extruded material in the same point. Same problem with mk2s
Re: Extruder is skipping steps on purge line
I had this on MK2s only very rarely. Here it is for all prints I am doing, without exception
Re: Extruder is skipping steps on purge line
Could be change in steps per mm causing slightly more filament to extrude for the purge. there isn't much else it could be i think...(assuming the gears don't add more resistance to extrusion) unless Z is too low but if it was it wouldn't be by much. you could just tune the start g-code to fix it if the rest is fine.
Re: Extruder is skipping steps on purge line
Do you mean that steps per mm are not adapted anymore to the new MK2.5 extruder?
I have disassembled the extruder and I found that the top PTFE tube was a slightly squished by a piece of plastic. I clean that hole and double check the hole between PTFE and Bondtech pulley. Unfortunately this does not change anything.
I removed the genuine E3D silicon cover, same result.
Something else I could observed is that my bed seems to be badly leveled (front the front, on the left side the level is bigger than on the right side) and I could not correct it with the bed level correction menu. Does any heard about something wrong with this function on MK2.5 3.1.3-RC1 firmware?
I am currently printing a Benchy to see if it is only a problem with the first layer / first purge line
Re: Extruder is skipping steps on purge line
My extruder steps setting got reset to its new default for the MK2.5 (133.0) as soon as I flashed that firmware. From memory, it was something like 168 for the MK2.
Re: Extruder is skipping steps on purge line
Ok, mine is at 133 as well 😉
Benchy as small holes in sharp angles and first layer is too low. I am going to increase temp and first layer height. I'll try tomorrow
Re: Extruder is skipping steps on purge line
Ok new benchy was not better.
I am currently printing a new benchy with Prusa PLA and it did not skip any steps! Nozzle was a bit clogged when I switched filaments. I have another genuine E3D nozzle to test after
I found this issue on the extruder that might be part of my issue :
https://github.com/prusa3d/Original-Prusa-i3/issues/51
https://shop.prusa3d.com/forum/original-prusa-i3-mk3-f30/any-ideas-how-to-get-this-flexable-material-to-pri-t14765.html
Re: Extruder is skipping steps on purge line
So I have swapped the nozzle and it is better. I also switched to Prusa PET and Prusa PLA only for my tests. I do not have skipping steps anymore (do not know with my previous filament).
However, it seems that my bed is very uneven. I am not sure I will be able to fix this via the bed leveling correction menu
Left :
Right:
Re: Extruder is skipping steps on purge line
Problem solved!
The main problem was the nozzle, I swapped to a new one.
One of the standoff under a corner of the bed was screwed deeper than others, squeezing the shim/washer (the screw on the other side has hex profile scratched). I took a standoff and shim/washer from the MK2s bed. After a careful bed level correction (using this model on thingiverse : https://www.thingiverse.com/thing:1776031 , thanks to him) I could get a perfect first layer all around the heated bed.