Prints quality not the same as it used to

[Shinao 0]

Hi, for more than a month now my print quality with default settings has greatly reduced, I have to tweak the settings to get something partially correct for each print.

As you can see, the default normal quality from my UM2 is ugly, if I slow down to 50% I get OK print, but if I also just change the temperature, I've got the same result. The best print (not ideal though) is when I slow down AND increase the temperature.

I've tried to reset my UM2, upgrade firmware, change materials used, changed models : same problem.

Does this mean anything to you the problems I encounter ?

Thanks

Edited September 7, 2016 by Guest

[neotko 1,417]

Have you check the ptfe coupler?

His normal lifespan it's 100-200h printing at pla temperatures and for the tfm that comes on um2+ it's around 500-1500h+ hours. How much hours print time has your printer since you had to change it?

When it degrades the tip starts to change at generates more friction when the pla pass through. That could explain how printing slower or at higher temperatures can fix temporarily the print quality.

Check this: https://ultimaker.com/en/resources/19619-ulti-evening-maintenance

Edited September 7, 2016 by Guest

[Shinao 0]

Hello neotko, thanks for your answer.

I don't think I have more than 100h on my UM2+, looks clean too :

I searched for other causes. Dirty nozzle ? it's only in appearance though, cannot seem to clean it, I've tried.

My filament appears to be really under stress with my feeder. It has always been the case though, even at the beginning with the filament given, it grinded a few times. I'm already at the lower pressure :/

[LePaul 354]

What are the results if you do an Atomic cleaning? What's the other end of the coupler look like?

[Shinao 0]

Looks good, cone shaped for the atomic cleaning.

How do I remove it ? It seems a bit stuck, do I need to force it out ?

[SandervG 1,521]

Hi @Shinao, you may want to check the bottom of your coupler, instead of the top. It receives some pressure from the top due to the spring, but the heat is coming from the bottom and that is where you should see the degradation.

Your filament definitely does not look good.

Have you changed the tension on your feeder?

Can you post some photo's of your Atomic Method results?

To be sure, do you have an UM2 or UM2+?

[Shinao 0]

Hi SandervG, I have an UM2+. The feeder had always this problem from the beginning, I have cleaned it, changed the tension to the minimum, it's a bit better but clearly how can the minimum tension give so much grinding ?

Tension feeder

Top view coupler removed

Face view coupler removed

Coupler view 1

Coupler view 2

Atomic method results

[neotko 1,417]

The only problem I can see it's that the feeder tension it's on the minimum force, in theory it should be in the middle. All the way up its minimum force, all the way down its maximum.

[Shinao 0]

It's just eat through the filament if I make it lower and stop feeding though

[neotko 1,417]

Have you been able to test with other filament spool and the spring in between the top and the middle? (So 1/4 force)

Edited September 8, 2016 by gr5

[Shinao 0]

Yes I tried multiple brand of filament, same thing. I don't understand the thing about yop and middle ? Do you mean pushing to this line ?

[neotko 1,417]

Yea that point

[Shinao 0]

What kind of sorcery is this...

The prints appears good now. So it's grinding when there is too much or not enough pressure ? How to know the difference ?

Thank you !

[SandervG 1,521]

I don't think it should grind when there is not enough tension but maybe during the pictures you made something right that was wrong..

In theory I could imagine that if the tension was far too low, the knurled wheel would move, but the teeth would not be in deep enough to get a grip and push the filament up, and therefor it just moves past the filament leaving some scratches, or with the littlest of resistance it looses its grip. But that is in theory

[Shinao 0]

Ha ! I guess in theory it makes sense.

Just leaving the thread open/best answer in case the issue appears again magically, making sure. Thanks guys.

[SandervG 1,521]

Even with a best answer the thread stays open, so feel free to reward and select the best answer. In fact, if it would appear again, to you or a different user, being notified about what helped you in first instance is probably most appreciated

[Shinao 0]

Tada, so I went to make some of my prints I wanted to do but couldn't because of the issue.

This is what I get for the beginning and I don't want to launch a 5h+ print for nothing.

What do you think the problem here is ? At first I thought it was the bed adjustment that were wrong but it seems partially good on top left and good right side...

[neotko 1,417]

It just seems a bad level, also you only get that milky effect when the nozzle it's too close to the bed.

What's the height of the first layer you set on your slicer?

Edited September 8, 2016 by Guest

[Shinao 0]

I will reset the level then and see.

I use the latest Cura version at normal settings. The only thing I changed is 0.2 in layer height.

[neotko 1,417]

0.2 it's ok, but that first layers looks like less than 0.1. You don't need to run the calibration, just adjust the thumb screws bellow the bed (middle and front left/right) the same amount.

If you are looking for a really perfect level you need a gauge feller (supercheap) to have a real 0.1 height. I say this because when you use the um2 calibration the system expects a 0.1 distance between the nozzle/bed. Also to get that distance really perfect you actually would need to have the bed and nozzle hot (to atomic first on the hotend if you go this way) because the things when hot change of size.

If you just want a ok calibration use 0.25 for the first layer on cura (more margin of error) and allow the calibration card to just 'fell' the nozzle like just 'a bit' don't squish it.

[gr5 2,265]

I don't see anything wrong in the photo. Maybe you should circle the problem or explain it in words?

[Shinao 0]

@gr5 On some places it's like 90% transparent and other parts are opaque

I start my long print after fixing bed level, first layers looking alright

After an hour

What's going on with my UM2+ ? :angry:

[neotko 1,417]

Does that happen with all 3d prints? Have you check the layer view on the slicer to see if it's a gcode problem? That photos have low res, if you upload on this forum albums it's easier for us to opent he original and zoom, etc.

So, also, how does it look from the front? Does it change the z or it's doing the same without changing z?

So, check layer view, photos from other angle, and if possible check xray view on cura to see if there's a issue there.

Also you said 1h? What's the layer height of that print? Also post speed settings, etcetc

Edited September 9, 2016 by Guest

[gr5 2,265]

Having the bed a little out of perfect leveling is probably fine for most prints as long as the error is on the "90% transparent" end of things and not the "ropy and doesn't stick to bed" end of things. You should let your print go a little longer. By the 3rd layer it shoudl be great. No one will be able to see these inner layers, right? They will be inside the print.

Your photo is a bit blurry as neotko says but from what I can see it's looking quite good so far. Just a little bit of over extrusion possibly (hard to tell) and some weird stringies but I suspect by the 3rd layer it will be all good. If not then try lowering the temperature and possibly also the speed in the TUNE menu while printing.

[Shinao 0]

Thanks for your answer, I'm back with a bunch more result... not great.

The last photo the feeder pressure is at 50%, everything OK until the last hour where it does something I don't get, do you recognize any pattern to know why it's happening ? 12 hours for that :/

Thanks for your support though