UM2 Extruder missing steps

[qwarks 1]

Sometimes - not always, my extruder misses a step.

 

When the first layer is build, the extruder misses a lot of steps (my nozzle is not touching the platform).

 

My filament measures 2,85mm.

 

The tensoin on he extruder i tight enough not to grind the material if it gets stuck.

 

It seems like the extruder motor is not powerfull enough to put enough pressure on the filament?

 

What could be wrong?

 

This is what a print with alot of missed steps looks like.

 

 

[DidierKlein 729]

You're experiencing under-extrusion.

A lot of different factor can cause this.

What are the printing settings you use?

If the first layer is under extruded it could be that:

1. The build plate is too close to the head, trying to print a 0.3mm layer if too close the extruder will have difficulties.

2. The temperature is too low

For the rest of the print you can check how your um2 does in extrusion terms with the cylinder test:

http://umforum.ultimaker.com/index.php?/topic/4586-can-your-um2-printer-achieve-10mm3s-test-it-here

You can also check this link for more information on under extrusion:

http://support.3dverkstan.se/article/23-a-visual-ultimaker-troubleshooting-guide#underextrusion

Possible causes:

Temperature too low

Speed too high

(both of the above)

Partially clogged nozzle

 

[anon4321 16]

Didier has the most common causes. In rare cases, the extruder driver overheats and shuts down briefly. If that is the case, you either need better cooling for the driver or reduce the driver current.

 

[qwarks 1]

Thanks for the answers.

Im using the settings that came with Cura, havent changed anything and it has been running fine up until now (Speed is 50 as the standard setting).

The buildplate is far enough away from the nozlle, i can easily slide a 90gr paper under the nozzle.

The temparature is between 210 and 215.

If it is a clogged nozzle, how do i un-clog it?

I will try that cylinder and post it.

Thanks guys.

 

[DidierKlein 729]

for un-clogging the nozzle try the atomic method:

http://support.3dverkstan.se/article/10-the

It can also be that the filament you use is reaching the end of the spool and it's harder to print?

Maybe you can try printing a bit hotter

 

[qwarks 1]

Thanks so much Didier.

I will try the atomic method after it is done with the tube test im printing right now.

The spool is almost new, but i will keep an eye on that when it comes to the end.

I will get back when i have tested these things.

 

[qwarks 1]

OH MY GOD !!!!!!

Used the Atomic method and here is the results.

Before Atomic method:

After Atomic method:

The extruder started missing steps at 8mm3/s but as you can see it still printed fine all the way up.

Thanks again, you saved my day :smile:

 

[DidierKlein 729]

Not perfect but should do the job

On the first attempt under extrusion appears after 5mm3/s a UM2 should reach 8mm3/s with no problems and well tuned UM2 can go up to 15mm3/s

Glad it helped

You can change somethings to have a better extrusion like the feeder design for example.

 

[qwarks 1]

Thank you Didier.

I will try to look further into this.

Right now im printing the part that failed before and it looks great :-)

 

[DidierKlein 729]

Have you printed with ABS before ? (i assume this is PLA?)

It is also possible that some small particules of the feeder have reached the nozzle and clogged it partially

 

[qwarks 1]

You are very right Didier.

I have been experimenting with PP and ABS, and experienced grinding on the extruder with those two materials.

Actually when i think about, it was after i tried printing with those materials that i first saw this extrusion problem.

If i need to set the current up at a later time, how is that done? Is this done on the circuit board?

 

[DidierKlein 729]

The feeder current?

It's in the gcode but i'm no expert there's a topic about that somewhere in the forum...

like this:

http://umforum.ultimaker.com/index.php?/topic/7892-real-bad-chewed-filament-girl-needs-help/?p=73966

When printing with ABS or other materials and switching back to PLA it's always a good idea to do a couple of atomic pulls in order to clean the residues