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Under-extrusion after moving printer  

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Mike
 Mike
(@mike-10)
New Member
Under-extrusion after moving printer

I've had a MK2S for about 4 years now, printer has been extremely dependable, rarely an issue. A few days ago, I noticed some noise coming from one of the linear bearings, so I decided to put a few drops of oil on each bearing. I flipped the printer on it's side, on the front, back, and upside down to get oil onto each bearing. Ever since, the printer seems to be under extruding very badly - I can't get a first layer to stick at all. 

I've removed the nozzle to confirm it's clear, checked the hot end for debris, done a couple of cold pulls as described on the Prusa website... nothing seems to be helping. Since I had moved the printer, I performed an XYZ calibration, which passed. When I try to run the Live Z calibration, the single line will lay down, but as I adjust the Z value lower and lower, it seems to get even worse instead of squishing out/flattening. The small square at the end of the print usually just turns into a blob, but when it does sort of stick to the bed, it looks exactly like under extrusion. 

I've tried multiple spools of PLA, stuff that was printing fine just a few days ago. If I remove the idler roller door, I can manually push the filament through the hot end without too much resistance. I'm not sure what else to do - anyone have any suggestions?

Posted : 23/03/2021 12:43 am
Diem
 Diem
(@diem)
Noble Member
RE: Under-extrusion after moving printer

Is it likely that any of that oil dripped, trickled or oozed into places it shouldn't?

Degreasing the plate and the filament path might help...

Cheerio,

Posted : 23/03/2021 10:07 am
Mike
 Mike
(@mike-10)
New Member
Topic starter answered:
RE: Under-extrusion after moving printer

@diem

The oil was applied directly to the bearings with a tiny needle, no dripping. I've cleaned the bed, and the issue is not bed adhesion. 

I've done a couple more cold pulls, and run the first layer calibration several times. What I'm getting consistently at this point is the nozzle wipe looks good, and then first 40 - 50mm at the beginning of the print is properly squished down on the bed. After that, the filament is clearly under extruded for the rest of the print. 

I've adjusted tension on the idler bearing, with no impact to the extrusion. I've taken the nozzle off and visually inspected it, no blockage at all. I'm stumped. I've ordered a couple new nozzles, and will try replacing the PTFE tube in the hot end. What's killing me is that this printer has been very consistent for the last few years, and now I can't get it to print at all.

Posted : 23/03/2021 12:41 pm
Diem
 Diem
(@diem)
Noble Member
RE: Under-extrusion after moving printer

@mike-10

Have you tried drying some filament?

Cheerio.

Posted : 23/03/2021 5:38 pm
Frans Krau
(@frans-krau)
Trusted Member
RE: Under-extrusion after moving printer

Hi Mike,

to be shure the path of the filament is ok: what happens if you extrude manually 100 mm? Is there 100 mm feeding of the filament? Is the extruder clicking? What happens if you manually reverse the extrusion - 10 mm and then manually extrude + 50 mm?

to be sure that the extruder motor (and its electricity cables/connections) behaves ok: Is the extruder motor turning while extruding? during the calibration?

 

Frans

 

 

 

Frans

Frans Krau
Europe, Holland, Apeldoorn...
Posted : 25/03/2021 3:43 pm
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