Very frustrated with Ultimaker 2+ layer issues

[cekuhnen 1]

Ultimaker 2+.  PLA    Using glue stick recently

 

I cleaned calibrated the printer but printing with it is a hit or miss

there is always the issue of under extrusion

 

sometimes this happens already on the glass surface 

sometimes and mainly this append in the part

 

the printer was not used that much and worked perfectly before - was not used for over a year and a half 

attached are some images to show the issue

 

i had the feeling this might be a feeder issue but mainly the test extrusion of material before printing looks amount wise fine

and also based on the nozzle and layer setting I get different results.

 

any help from Ultimaker would be highly appreciated 

 

 

 

 

[cekuhnen 1]

After this crap print

 

I calibrated the print bed again with the build in function and then with some test prints to check corners.

I had one 98% good print that showed only at two layers issues - which however is already not good

 

and all following prints are horrible again. Below are two print attempts of the same mode ...

 

@gr5 I am not sure if you could maybe point me towards a solution.

 

Can the PLA be old or the print glass surface have issues?

Edited July 9, 2018 by cekuhnen

[geert_2 557]

To me it looks like there might be multiple issues?

 

I have the impression that the bed is too high, and thus the first layer is not squeezed into the glass enough and does not bond well?

 

Maybe your bonding method also needs adjusting? For example if you use the glue stick, wipe it with a wet tissue after applying, to get a very thin layer? Or clean the glass and apply the bonding more often?

 

And then of course there is underextrusion at irregular intervals, which could have lots of causes: partially blocked nozzle, too high printing speed, too low temperature, spool near the end and wound too tightly (this acts as a spring that resists unwinding), deformed teflon coupler, wrong feeder pressure, dirty feeder, wrong filament diameter, dirt in the bowden tube, or other things along this line...? But I am not familiar with the UM2+, so difficult for me to say, it is a bit of guessing.

 

[cekuhnen 1]

I did a test cube print and it failed too

 

So I took off the print bed and washed it both sides and put it pack and the test cube print worked again instantly

 

Then i removed the parts to print the main design a s again this failure

 

this is just bonkers

 

Printing the test cube again works

 

Edited July 9, 2018 by cekuhnen

[cekuhnen 1]

All I did was to adjust the feeder tension and this seems to have helped

 

[cekuhnen 1]

Maybe I should not have praised the day before watching the even TV scheduke

 

totally inacceptable layer gabs

[prb4 6]

That's under-extrusion.

Most likely caused by a blocked nozzle.  You need to do some atomic pulls to clean the nozzle.

 

 

[BrayChristopher 36]

It also might be time to swap out the Teflon collar above the nozzle.

[MechDesigner 3]

you might also want to add more brim around your part,  I use 8mm.

it will help with adhesion.  also check into 3Dlac spray,  works great,

 

https://www.amazon.com/Adhesive-Warping-Printers-ORIGINAL-canNOT/dp/B01BVM54XI/ref=sr_1_1?ie=UTF8&qid=1531502759&sr=8-1&keywords=3dlac+spray

 

[cekuhnen 1]

It seems to me this was really more a feeder issue not nozzle or print plate.

I have 2 0.8 nozzels (actually 2 complete nozzle sets) and the issue happens mainly with 0.8, less with 0.6 and hardly at all with 0.4

 

I changed the tension and it seems to have helped.

 

I will do another big print today.

[geert_2 557]

If it happens mainly with the 0.8mm nozzles, a factor could be temperature: it requires 4x more heat to melt enough plastic in the same time for a 0.8mm nozzle than for a 0.4mm nozzle (twice the diameter = 4x the surface). So you might want to reduce speed and/or increase temp. Try adjusting these on the fly on a test piece, and watch what happens.

 

[cekuhnen 1]

Just now, geert_2 said:

If it happens mainly with the 0.8mm nozzles, a factor could be temperature: it requires 4x more heat to melt enough plastic in the same time for a 0.8mm nozzle than for a 0.4mm nozzle (twice the diameter = 4x the surface). So you might want to reduce speed and/or increase temp. Try adjusting these on the fly on a test piece, and watch what happens.

 

 

I will test that. With the last print however you are able to see that the print started well in-between had massive under extrusion and then finished well.

 

I would expect a no print at all or well print which is why I started to think that this must be a feeder issue