Kwallnation

We have solved the problem. We ran out of all ideas and decided to finally try replacing the coupler. We bought the long lasting "permanent" fix coupler from gr5 and installed it. It worked phenomenally and the prints are coming out amazing again. Initially we didn't think it was the coupler because when the problem first started we had replaced the coupler 3 weeks before. I forgot that in those three weeks, we had printed for 2 weeks straight, 24/7 for a large project we were on. This wore out the coupler and thus this new coupler fixed the problem. Thank you all for the help!! -Kwallnation

Hi! Has anyone come up with any ideas?

Hi Everyone! I apologize for not posting in a few weeks, but after tinkering a little bit I had some interesting results. Since my last update I installed an Olsson block and a new temperature sensor (which I broke while trying to install the new block:P). I also completely cleaned and re-greased the z-screw and attempted a re-alignment procedure that I found in another forum thread that solved someone else's problem. However, I continued having the same problem with inconsistent layers throughout my entire print. It seems like a slightly different issue than what others are having, as theirs seem to be only one one layer on a consistent basis. My prints seem to have inconsistent layers throughout. However, something interesting happened when I decided to try a print at .06 mm versus my usual .1. The problem seemed to disappear entirely! Then, when I went back to printing at .1 mm again (using the mini calibration test that comes with the printer) the problem returned. Does anyone have any ideas as to why this happened? And if so, how I can fix it so it prints normally at .1 mm again? Thanks so much for all of your help! (And sorry for such a long post )

peggyb: That is my problem too! When I lift my UM2 bed up by had I hear crunching noises in certain spots! I don't know how to solve this!

@gr5: I moved the build plate up and down and there was no play in the Z-screw. I couldn't move it at all without the shaft turning. It appears that this is not the problem that is causing the Z-banding in my case.

Thats a very interesting theory! I will for sure try it and get back to you with the results. Thank you.

Alright, thank you. I also just disassembled and cleaned out both the Bowden tube and the feeder. I am waiting on a test print to see how these changes affect the quality.

Yes, I moved them up and down but if I raised the bearing to the top of the Z-guide rail and released it, it would tend to stick in some places and would not independently slide to the bottom of the shaft. Could this be a problem with the guide rods instead of with the bearings? If not, any ideas??

After using Colorfabb filament, print quality has improved but the problem is still there. We have just tried cleaning off the Z-screw as well as removing and trying to clean the bearings; however there is still some sticking as I move the build plate up and down. Any advice to fix?

Thank you very much for your help. I will try it out.

I changed around the filament and it appears that the filament was defective because with a different spool it prints just fine. I will take a look at your solution though. Also, this is the second time that my Ultimaker filament has come defective, is there another brand that would work just as well? Preferably in the US?

Ok thank you for the advice!

We currently use 2.85 mm standard ultimaker brand filament.

Yes, there are some "tocking" sounds but only on the first few layers.

I just replaced the PTFE coupler two weeks ago, but I will check the bearings. How would I access the bearings?

I laid the spool on the floor and the problem seemed worse. Are there any more suggestions that you have?

Perfect thank you. I will take a look at these solutions and see how they work. Thank you for the help.

Will do. I will see how it affects the print quality. Thank you. Last thought. Could it be the tension in the feeder screw? I haven't touched it since I bought the machine but I am just thinking of every possibility.

I just checked and I did properly grease the z-screw. Also I printed a lightsaber (both skinny and tall) which was the one print that printed extremely well on the almost empty spool. I believe the height of this print would have come out much worse had the z-screw been the problem. Therefore, I am back to believing it is a problem with the spool. Could it be that the filament on the spool is not wound tightly enough?

I attempted to grease it although I don't know how effective it was. Could that be whats causing the issue?

The room is air conditioned but there is no vent close by. (more than 12 feet away). We did have one extremely clean print with a nearly empty roll but all other rolls do the same thing as this new roll.

Another print just finished and it looks the exact same way. Any help would be very appreciated.

.1mm 210 c PLA 50mm/s (all standard settings for the "Normal" setting on Cura)

Hi, So I've been printing with the UM2 for about ten months now and recently it has been printing uneven layers. It looks similar to how under extrusion looks, but the layers are solidly formed. As a result, I can see all of the layers that it prints. They are not flush up against one another and seem to look a bit staggered. I replaced the Coupler two weeks ago so that is not the problem. I have also done several atomic cleans and am using Ultimaker Filament. Does anyone have suggestions on how to fix this? I suspect that it could be due to difficulty of the feeder to turn the new spool of filament, but I don't know for certain. Thanks for the help!

Thank you, I was going to try to insert new filament into the feeder to push it out. I will try it! Matt