Serious problem with printing  

Re: Serious problem with printing

I think that you have not found the correct Z level on the first layer. The skirt around your items looks round, it should be more flattened. So you should try to lower the nozzle slightly.

Regarding the temperature change during printing, it is quite normal. If you look under the "Filament settings" menu in Slic3r, you will see how and when the temperature will change.

Do not make any custom settings for the filament you are using. If you run PLA, use the "Prusa PLA" profile. It is calibrated to work on many different PLA's.
You write that you use different layer heights like 0.15, 0.20 and 0.30! 0.30 is not a calibrated layer height so avoid it.
Use "0.20 mm FAST MK3", it always works, and together with PLA it's perfect to print.

Use the calibrated print profiles found in Slic3r and do not make any custom adjustments before you know what you are doing.

Then adjust the Z level, wash the bed with detergent and water so you have the best prerequisites for a successful printing.

If you still have problems, check the printer that all screws are tightened correctly, that the X and Y axle end pulley's run smoothly and that the extruder is properly adjusted to feed the filament as it should.

Edit
That the printer stops and asks you to change the filament is caused by some shiny filaments. For these filaments, you avoid problems by temporarily turning off the Filament sensor.

Re: Serious problem with printing

All of the above is good advice.
For bed cleaning get IPA Isopropyl Alcohol with the highest concentration possible (drug store)

Print the included test objects with the standard G-Code files!! That shows that everything is working.

FDM printing can be very, very sensible tot even small changes.

What is your ambient temperature?
I read that people had some light jams at higher ambient temps with PLA. I print at 20 dec C ambient and have not had any.

Re: Serious problem with printing

All of the above is good advice.
For bed cleaning get IPA Isopropyl Alcohol with the highest concentration possible (drug store)

Print the included test objects with the standard G-Code files!! That shows that everything is working.

FDM printing can be very, very sensible tot even small changes.

What is your ambient temperature?
I read that people had some light jams at higher ambient temps with PLA. I print at 20 dec C ambient and have not had any.

If you can't get over 90% locally, see if Amazon has it and compare prices between the different sellers. I bought a case of 16 ounce (~475 ml) bottles of 99% for a really good price.

Re: Serious problem with printing

Thanks for all replies

In the meantime I went throug the whole forum and found out that my problem is similar to this one described here

https://shop.prusa3d.com/forum/how-do-i-print-this-printing-help--f63/pla-filament-problem-extruder-stops-extruding-fila-t23601.html

Unfortunaly in the mentioned thread there is no working solution identified yet (although many hypotesis were tested)

Luckily I found the other thread

https://shop.prusa3d.com/forum/others-archive--f66/clicking-printhead-filament-stuck--t14916-s90.html

The solution which is purely mechanical is described here

- The official documentation for E3D V6 hotend
https://e3d-online.dozuki.com/Guide/V6+Assembly/6?lang=en#s77
- Youtube video, which perfectly explains what I was thinking about

I checked I I was indeed missing this hotend collet clip. I made it from the metal washer (my printer was already disasembled). Now I need to assembly the printer again and check if it works (I DO HOPE IT WILL)

I'll let you guys know as apparently my printed was sold me without this piece 🙁

BTW - I'm not entirely sure why such important topic was put in the Archive (Other) category ... It looks like this is a problem for many people out there

Re: Serious problem with printing

Symptoms
After approx. 50-100 layers (0,2 mm) when the parts (mentioned above) are approx. 1-1,5 cm high problems with filament starts. Basically it doesn't flow properly. Extruder is moving upward (like printing layers) but the filament is not flowing from the hot end correctly. Few times I was asked to unload the filament and load it again even though there was enough filament on the spool.

It happens every time with the element no. 4 and happened couple of times with parts 1-2

I was printing with Prusa PLA and tried different setups
- used slic3r and Prusa tools
- used different layers (0,15; 0,2, 0,3)
- played with temperatures (usually set 215, increased to 218). What interesting that i use default setup for PLA (215 for heatend but after approx. 15 min. the temperature drops to 210 itself - unless I increase it manually)

It sounds like you're getting a clog or jam or something after a print has been running for a few minutes.

I think you can rule out problems with your Live-Z adjustment because it's not happening on the first layer.

I think the collet clip may be a red herring. The MK3 uses a slightly modified E3D, and mine does not have a collet clip and prints just fine.

The fact that it happens a while after you start the print suggests to me that it could be heat related. Another possibility is that you've got a bit of gunk in the extruder that's sometimes clogging it but not consistently.

Are you hearing a "clunk clunk" noise from the extruder motor when this happens? The noise means that the motor is skipping steps--which probably means that thee's a clog below the drive gear that's keeping the filament from moving. If you're not hearing this noise, I'd check to make sure the bondtech gear is tight on the extruder motor shaft, in case the problem is just a loose gear.

Have you gone through the steps for removing a clog in the extruder (getting the cleaning needle up in there and fishing it around a few times)? It would be good to rule that out.

If it is heat related, my suspicion would tend towards the heat sink/heat break/hot block/PTFE tube not quite being properly assembled.

Finally, the behavior you're seeing with the temperature (temp drops to 210 after a few minutes) is normal. The default PLA profile has the first layer printing at 215 and other layers at 210, so there's a command in the gcode to set the print temperature to 210 after the first layer is done. I think any print temperature issues are also red herrings.

Re: Serious problem with printing

I only checked the first link you posted in your last post, and that is referring to the PLA jans caused by borderline cooling capacity of the MK3 extruder.
From what I read It is only happening with PLA AND when ambient tmeperature is high.

Fixes are lower ambient temperature and the new R3 extruder design which increases cooling efficiency of the extruder.

Check Prusa’s big summer announcement.

One tip: Follow the proven solutions
The MK3 is a really sophisticated device and changing anything can have a lot of unexpected side effects

Re: Serious problem with printing

Thanks guys for valuable tips and directions.

Last night I assembled the printer again with the collet clip installed as well as I retuned the printer. The results look promising but I definitely need to spend some more time on printing before I'll be able to tell whether it’s working correctly or not.

So far I managed to print 1) prusa logo and 2) spool hub – both successfully

Prusa logo
- I noticed some small melted spots on each letter. Any ideas what could cause this? My guess is to low live Z axis adjustment (currently -0,6).
- Logo was printed directly from SD card from the default prusa file
- First layer looks pretty good

Spool hub
- looks pretty good (before it failed twice). These melted spots are much more smaller
- first layer looks as the hotend was too high

I’ll make some more testing and keep you updated!

Re: Serious problem with printing

[...] - I noticed some small melted spots on each letter. Any ideas what could cause this?
That's probably the little "wiggle" spot created by the printer doing the "wipe" movement before switching layers. It will be exaggerated if you're over-extruding. You can try turning off the setting in your slicer software. You may get more stringing as a result.

Unfortunately, your pics aren't showing so it's hard to say for sure.