So, I'm having ssome print issues, with a lot of underextrusion occuring. I've recalibrated the AFC software bowden length, hub lengths, as well as the extruder rotation distance. However the underextrusion remains. I did hear what sounded like motor slippage originally, so turned the amps up, and now hear occasional distinct teeth skips.
One thing I've noticed during print, is that the bowden between the NightOwl and printer is getting compressed/crinkled.. this leads me to think there is a mismatch between what the extruder is pulling, and the NO pushing. Is there a way to check this, beyond just rerunning test prints?
#Possisble sync issue between extruder rotation_distance and NightOwl Stepper rotation_distance?
modest bramble
modest bramble
should also note, I'm using a TN v1 buffer, and it's sitting at fully compresssed during the prints, if that helps provide some extra info.
serene tinsel
Sounds like your TN is not working correctly, verify that both switches activate when moving it manually, also verify that the PTFE tube is not moving in the TN. If it is adding a clip should help keep it from moving
remote jacinth
you can always verify your NO rot_dis is correct with lane move commands when its not loaded
modest bramble
Sounds like your TN is not working correctly, verify that both switches activate...
Had a few issues with the TN (tube in too far), but I can verify its working correctly now, and if I manually move, it triggers correctly expanded and compressed. I can also see it moving during filament load, but then sits at fully compressed during prints.. and it looks like the bowden tubing is being put under compression.
modest bramble
you can always verify your NO rot_dis is correct with lane move commands when i...
Can you expand on this? is it basically running same process to calibrate extruder - feed through a certain amount of filament, measure it's correct, adjust rot distance if not?
remote jacinth
It should be necessary to adjust so long as it’s not multiple mm off. But yes
modest bramble
ok, cool. I'll check it for my sanity. tried a lot of thing recently, and test cubes still look like classic case of underextrusion.. even on top layers
remote jacinth
ok, cool. I'll check it for my sanity. tried a lot of thing recently, and test c...
Did you check your switches are working and correctly located?
Nvm I see it now
modest bramble
Nvm I see it now
all good, yeah, all switches are working fine. Just got to stop shoving the PTFE tube too far!
remote jacinth
Do you have a rubber band around the TN?
serene tinsel
all good, yeah, all switches are working fine. Just got to stop shoving the PTFE...
- Remove the inlet PTFE tube
- hold close TN buffer
- Insert inlet PTFE tube until it hits slide end
- Insert collet clip
- pray and hope that it stops sliding inward
😬
remote jacinth
Having the switches work correctly usually keeps the tube from sliding too
modest bramble
Do you have a rubber band around the TN?
I did, but I took it off to check it wasn't causing an issue...
modest bramble
Current test prints.. shocking
modest bramble
think I've found the issue.
NO rotation distance is not feeding enough. Ran a BT_Lane_Move to feed 100mm, have 24mm left at the end of the move...
run the test 6 times back to back, meassure 44mm after each time, instead of the correct 20mm... seems the NO stepper rotation_distance is well off!
remote jacinth
did you use the BOM motors?
also its not listed as loaded to toolhead right? cause then the TN offsets would be applied
modest bramble
did you use the BOM motors?
I got my kit from Aliexpress (triangle lab)
remote jacinth
gear_ratio: 50:10```
Is this what you have in your cfg?Lane 1 (Lane2 is the same)
remote jacinth
well thats weird seems like the ratio must be off
modest bramble
yeah. Original value is there (4.65). the new distance (as calculated from the tests) is 3.686
big difference
remote jacinth
you'll want to redo bowden calibrations after changing that
modest bramble
thanks for the heads up
remote jacinth
thanks for the heads up
also its not listed as loaded to toolhead right? cause then the TN offsets would be applied
modest bramble
no, only ran the inital load, filament currently is just beyond the TN atm
remote jacinth
ok but as we have discussed that doesn't mean that AFC doesn't think its loaded already
look at the gui
modest bramble
If I hover on the filament, it says 'load lane', so I'm going to assume it knows it's not loaded 😉
remote jacinth
the top section where it says buffer not active is key
modest bramble
New value is feeding bang on the right amount, measured now.
I'll recalibrate everything now, as just redid Lane 1, and dist_hub has changed a lot.. so appreciate bowden length will need redoing also as mentioned
modest bramble
I can only assume something is off with the gearing... maybe my steppers have a smaller pinon or something. Never checked tbh in build, all seemed to go together fine
remote jacinth
well if you take it apart some time it would be good to confirm if you for some reason have an 8t motor instead of 10
modest bramble
confirmed. Motor has an 8T gear.
Lane 1 had a grub screw come off on the bondtech gear... good thing I've been doing all my cals on Lane 2
remote jacinth
ah well that'll do it. thats not to the BOM then
modest bramble
First test print done now. No noises during printing, and I'd say it looks way better...
remote jacinth
bigger ne is before right?
modest bramble
yeah