Print Failing Mid-Print
Hi Everyone,
I've been trying to figure out what has been going on with our MK3S printer. For the past year it has been printing daily almost around the clock as part of our printer farm. We have been doing periodic maintenance/service to keep it running and it has been running like a champ until lately.
We now seem to be having prints stop extrusion mid print. We will get clicking on the extruder as it can't seem to push filament through. We have gone through all the typical things like cold pulls, nozzle cleaning, heat creep investigation etc. Below is what we have recently done and we are still seeing consistent failed print mid-print (no extrusion)
- NOTE: We are printing with PETG
- Tried different brands of PETG
- Extruder Trouble Shooting
- Checked alignment of extruder teeth
- Checked to see if there was any debris in the extruder teeth
- Checked to see if there was any filament particles near the extruder that needed to be cleaned
- Adjusted the tension screw both tighter and looser
- Heat Creep Trouble Shooting
- Replaced both fans
- Added more thermal paste to the heat break
- Clogging Trouble Shooting
- Used the acupuncture needle to clean nozzle
- Changed the nozzle with a brand new one
- Changed heating element (maybe wasn't getting hot enough)
- Changed temperature sensor (maybe was reading temperature wrong)
- Replaced the PTFE tube with the extra one from the provided spare parts (thought it was a pinched tube)
- Double checked to make sure the PTFE tube is seated and no gaps (thought a clog might be forming between the tube and heat break)
Essentially we pretty much have a brand new hot end. Only thing that hasn't been replaced is the heat break.
When we heat up the printer and load filament it seems to load fine and flow well. But we have noticed lately that our first layer is rough compared to the nice smooth layers put down before. Which would lead me to believe there is under extrusion happening. But for the life of me I can't figure out what might be blocking the flow of filament.
This has been a great little printer for us and we're trying to figure out how to get it back on track
RE: Print Failing Mid-Print
Here is an example of the rough print that we are seeing when it is laying down the first layers.
RE: Print Failing Mid-Print
We have also now replaced the heat break and we are still getting failed prints mid-print
RE: Print Failing Mid-Print
Make a picture of the first layer( and not a few layers), and zoom in.
Water in filament? dry it in a oven, try a new roll. water in filament or clogs , move extruder to higher position, then extrude by hand, filament should have no bubbles(water), it should be in a straight line, and it should be thick enough(partial block if it is to small).
Try printing with a higher temperature, to see if it flows better.
Printing in a enclosure? Blow extra air in the enclosure, it is now warm in the summer, on https://www.thingiverse.com/ you also fins a extra fan holder for on the extruder, this cools it very good and les heat can go to the filament.
RE: Print Failing Mid-Print
A new sheet will stick less then a used one.
PLA sticks more difficult on a powder coated sheet. Is still possible settings need to be more preciese.
This how I work on a pei sheet(there are always exceptions):
Most important to 3d printing is:
1. 3d print will never be like start and i have the print, there will always be problems!!!!!!
2. A clean sheet, use dish soap, then you can print on it. A few prints you can use alcohol, then again dish soap,
big flat models and models with small footprint on sheet- use glue stick(and not every glue stick is the same,
use one that makes a thin layer), and big flat models and small footprint, use a big brim attach to model so footprint is bigger.
Petg sticks to much on the pei sheet, use window cleaner, this leaves a layer on the bed, so it does not stick to much.
3. To get it stick very good, a 100% first layer is very important, see youtube for movie on this.
Every new print watch the first layer, and look if it is 100%, this will also prevent a big ball of filament on your nozzle wen model let loose during printing.
Extra: (normally not needed).
First layer, print hotter.
First layer slower.
Bed more heat.
Most problems are first layer to get this 100%, and bed not clean.
Bad filament is possible, or filament with water inside.
Move extruder to the top and extrude filament, it should go straight down(if not, nozzle possible blocked),
it should be thick enough(if not, nozzle possible blocked, or partial blocked), (do a cold pull),
if Bubbling during extrusion then it has to much water inside.
Check after the first layer is ready, then you see if it sticking enough, and not releasing and sticking to the nozzle.
If you see white spots like a bubble on the bed, then filament is releasing from bed.
Also no gabs between lines should be visible.
Use 7x7 calibration for first layer, see settings in the printer.
Search for " 3D printer first layer problem Calibration process" on youtube, movie on first layer calibration, with a good zoom in.
RE: Print Failing Mid-Print
You may want to have a look at my post in a different thread.
RE: Print Failing Mid-Print
You may want to have a look at my post in a different thread.
Thanks!
As a note, we did switch out the heat break with a new standard one and still have the issue. The strange thing is that we have another 3S printing right beside it (exact same environment) and it isn't having issues. Our first layers are now coming out beautiful, but we still get failed prints mid way through.
We have tried multiple different kinds of filament to see if that helps with no better results. Both printers are printing the exact same gcode files that they have been printing for the last 12 months (small printer farm). So adjustments to retraction speed etc don't seem to be a likely solution as nothing has changed in the files that they are printing.
When it stops extruding (printing in thin air) the extruder motor is still trying to pull but it seems like it is clogged. This leads me to believe that for some reason the heat sync is not getting cooled enough causing heat creep and that the extruder motor itself is fine. We have replaced the heat sync fans on the printer as well. The heat sink itself isn't a moving part, and just a chunk of metal, so I can't see it being the issue. Maybe I need to design some kind of dual fan heat sync mount or something?
Everything in the head has been replaced now except for the extruder motor and the heat block itself.
RE: Print Failing Mid-Print
The heatbreak where it is screwed into the heatsink usually is coated with a layer of thermal transfer paste (only on the heatsink side not the heatblock side). You could check that the misbehaving printer has a sufficient amount.
I saw no mention of that when you mention changing out the heatbreak for a standard e3d version.
RE: Print Failing Mid-Print
The heatbreak where it is screwed into the heatsink usually is coated with a layer of thermal transfer paste (only on the heatsink side not the heatblock side). You could check that the misbehaving printer has a sufficient amount.
I saw no mention of that when you mention changing out the heatbreak for a standard e3d version.
Hi there,
Yes there is a good helping of thermal paste on the heatbreak where it screws into the heat sync 🙂
RE: Print Failing Mid-Print
@tim-8 Are you sure the clogging is in the hotend? I always had a blob of compressed filament between extruder gears and PTFE tube. I believed it would be from the extruder gears stalling after the hotend jam but in reality this is the jam. My hotend is fine and always was.
You cannot unload/pull the filament with that blob so the filament solidifies in the hotend at cooldown - which looks and behaves like a jam.
My case may be special and PETG softens at higher temperatures but to find the difference between your two printers you could compare the extruder motor temperatures. Just an idea.
RE: Print Failing Mid-Print
On the forum a few users have with pla clogs .
You could try smaller retraction, speed change of retraction(in and out). search on forum for other users settings.
If it is heat, you could try to blow with a fan on extruder motor and higher on the printer, and try a few prints.
I have a mk3(no s), i change to a original e3d heatbrake without the 2mm opening, and i have a extra fan on the extruder motor, that blows to the top of the printer, and cools the extruder motor and gears, in the hope that the gears do not get hot. https://www.thingiverse.com/thing:2975582
I have a enclosure, and leave door open, except with ABS.
Every thing I print I use standard config, exzcept speed I slow down a little like the 180mm 200mm I use 120mm, And often 80mm I use 60mm,
And temps I change, often I use higher for PLA, and petg the standard temps or a little lower, depends what is on the box temps.
RE: Print Failing Mid-Print
If the stock heatbrake from e3d is better or needed I do not know.
I change this a long time ago, because I could not find why filament gets stuck during printing.
Try other things before you by a different heatbrake.
RE: Print Failing Mid-Print
If the stock heatbrake from e3d is better or needed I do not know.
I change this a long time ago, because I could not find why filament gets stuck during printing.
Try other things before you by a different heatbrake.
The Heatbreak is the last thing we have tried. We've listed everything else we have tried in the initial post.
RE: Print Failing Mid-Print
@tim-8 Are you sure the clogging is in the hotend? I always had a blob of compressed filament between extruder gears and PTFE tube. I believed it would be from the extruder gears stalling after the hotend jam but in reality this is the jam. My hotend is fine and always was.
You cannot unload/pull the filament with that blob so the filament solidifies in the hotend at cooldown - which looks and behaves like a jam.
My case may be special and PETG softens at higher temperatures but to find the difference between your two printers you could compare the extruder motor temperatures. Just an idea.
Thanks! We'll run it again and when it jams we'll open up the adjustable extruder door to see if there is a blob there. We can check the temperatures on the extruders as well.
RE: Print Failing Mid-Print
Update: Ok, so we even went out and purchased a fully assembled new hot end for the MK3S. That didn't make any difference either. We did however turn the print speed down to 60% and then everything started printing fine again.
I'm thinking it is our extruder motor that we will try and replace next.
RE: Print Failing Mid-Print
New update.. turns out our Extruder motor was going bad. Replaced it with a new one and the printer is back to printing normal at 100% speed.