TheStargazer

Hey Geert, Thank you for your response. 1) I have tried multiple computers, multiple different installs of Cura using different versions. No change. 2) I agree it is quite weird... It would actually be quite difficult to get the printer to do a fine mesh like this on purpose. 3) Have tried multiple SD cards. No change. 4) This patterning appears on all prints to some degree, even on the default "comes with the printer" g codes on the original SD card that came with the printer. (Hence the "Coffin's Cube" in my first image, that is the default gcode without any modifications on the original SD card) 5) Manually moving material works fine. I have tried reflashing the software on the printer and making sure I have the most up to date firmware. All good, no change. As requested by Torgeir, here is a print incredibly slow (at 25% speed): The problem still exists, but is not as obvious. You can see it in the first few layers, then it kinda blends together, but weird patterning is still visible in the walls of the print.

Today to double check I took a lot of the printer apart and oiled everything that could possibly need to be oiled, the motors, X Y and Z axes, etc... (Motors, X and Y axes with machine oil, the Z axes with the Ultimaker provided grease) No effect (as expected). Currently doing a print at 25% speed as requested by Torgeir. (I must hold the world record for number of prints of this particular rocket model that I'm using as my primary test print! And yes, I have used other prints and the problem also appears there as well)

Torgeir, Will give it a shot on a very slow setting and see how it works, but given both the internal thermometer and the external IR camera say the temperature is good, I'm skeptical this is the issue, however I have no better ideas! Neotko, Thanks for the feedback. Addressing your points one by one: - When I first installed the Olsson block it was touching the metal cap and giving a heater error. I have since increased the distance and there is now plenty of clearance. - Nozzle is not touching - Heat sensor is fully in. I do not have my camera with me today but I will take a photo tomorrow. - Coupler does not move. - Bowden tube is a little short but otherwise fine. Have tested using a tube a few centimeters longer and it does not appear to be an issue.

Ah apologies, I mis-interpreted your message. Yes the feeder tube is well locked. It has deep marks on it from where the "teeth" grip the tube, and it is all the way down to the teflon coupler. I can pull upwards on the tube with a large amount of force before it starts to slip.

Again, it "kinda" looks like under extrusion, but it is not uniform across a layer, and the problem is repeatable layer after layer in a way that makes patterns.

Ok, so I decided to do a set of test prints today experimenting with the feeder tube using a longer tube or shorter tube and seeing if it changed anything... And I discovered that the problem has somehow overnight become ALOT worse. Something seems to be slowly failing, causing the problem, but for the life of me I have no clue what it is. The motors all seem to be working well (both feeder, X, Y, and Z) Photos from today: IMGUR album: http://imgur.com/a/eR4pB

Torgeir, Thanks for your well thought out response. I agree it is a very unusual problem, that has us at our wits end. While we needed to shorten the feeder tube by approximately 1 cm due to some filament that became stuck in it, there seems to be plenty of slack. But to be honest, I've run out of ideas and a new feed tube only costs 20 euro so I'll purchase a new one and see if that helps at all... Will let you know how it works out.

Only parts that are not from Ultimaker are the PFTE coupler and the Olsson block. The "black residu" is just tarnishing of the chrome. Bit puzzled by that myself, but they're smooth to the touch and lubricated. I've just been using the lubricant that came with the Ultimaker2. Any suggestions on something better? Will print a few more test prints on Monday.

Anyone have any inspiration? Still having this error.

Owen - Yes. We're printing at settings that worked beautifully with this printer for ColorFab and PLA a few months ago, but suddenly are causing weird problems. It seems like something is changed / broken. SandervG - We have tried 3 new nozzles of different diameters. Still have the same problem. The coupler is a new after market one that came with our Olsson block. It appears to be positioned correctly as far as I can determine. Again, weirdly is prints fine in CF-20, but suddenly has this problem in PLA and XT....

I had this error after installing the Olsson Block. The Olsson block was touching my fan shroud, causing it to cool rapidly. We simply screwed the metal coupler slightly tighter into the Olsson Block so that the Olsson block was not touching the fan shroud and this solved the error.

An interesting point... We have tried a number of filament types (we have tried older rolls of filament and brand new rolls of filament, with the problem appearing with both) and have seen the problem with PLA and ColorFabb XT, but not with CF-20 for some reason? As I said, we have monitored the temperature of the hot end with a thermal camera and it is correct.

Unfortunately none of these feedback points are useful, as they're all basic 3D printing 101 troubleshooting tips. 1) PTFE is new 2) Print Head photo attached below as requested 3) Plate is releveled after every print. 4) We usually use a very thin layer of water soluble gluestick on the build plate when printing with ABS or ColorFabb-XT. Have not found it necessary for PLA. 5) All models. And it gets worse with bigger. models. Photo attached. The model is supposed to be a rocket and parts, with smooth cylinders. 6) We are not interested in changing the bottom / top thickness, as that would be hiding the problem, we are interested in identifying what has gone wrong with our printer and fixing it, not hiding the problems.

Colorfabb XT is the main filament we use here. I've tested several rolls, both old rolls and new rolls to see if it is a humidity / filament issue and it had no effect. To me it seems like it is a mechanical issue as it always repeats in the same places of the prints. When it is making certain corners, etc... It is generating these patterns, and also lots of pillowing. But 4-5 months ago it did not... If it were a filament / clog / feed issue I would expect the problems to occur randomly throughout the print rather than be reproducable. Today I checked the motors to make sure they were tight against their rubber bands. They were still acceptable, but I tightened them anyway and it had no effect. Reflashed the firmware for the upteenth time from Cura 15.04.4 but no effect.

Yup! Fortunately I have access to some cool tools here at work... Used an IR camera to get the exact temperatures of the nozzle at both 240 and 260 C set points. When the printer thinks it is at 240 it is actually at 241.3, when it thinks it is at 260 it is at 269.1. (The 260 setting actually going to 269 is actually a little concerning if I want to print in ABS but I fortunately don't do that often, for this issue it's irrelevant) EDIT: Hmmm Ultimaker didn't like the image files.... Here's the link to the imgur album: http://imgur.com/a/yqKVR

Remy, Thanks for the reply! Printer is in the exact same location as it was before, no changes to the room / ventilation. No feedback sounds from the motor. Bowden tube is fully inserted and clean of any damage. Also as mentioned in my original post, the nozzle is brand new. As mentioned in my original post, increasing the nozzle temperature to 260 will make the problem start to go away, but then I start having a lot of other issues from using a temperature higher than normal for my filament. Again, I am more concerned with what is causing the problem / why something suddenly changed. Yes there are measures I can take to force the problem to go away, but I'm more concerned with what is causing it, rather than hacking a temporary solution.

neotko, Thanks for the feedback! When first installed the Olsson block was touching the plate and causing the temperature to drop significantly to the point that we were getting heater errors half way through the print. We took it apart and cleaned the threads, making sure to screw the block in further the second time and now there is an approximately 1 mm gap between the block and the metal cap. I've monitored the temperature during a print and the heater does not seem to have any issue currently keeping up with the cooling since we screwed the metal coupling in further. At all times the nozzle is within 1-2 degrees of the set point.

Teeth marks on the filament are nice and light. Not too deep. No grinding visible anywhere on the filament and no particulates of filament in the motor. I have tried 1 "tight" print where I increased the tightness of the motor by a turn, and one where I loosened it by a turn, and did not see any noticeable difference in the print. Tried taking a picture but my camera is horrible at close ups and the teeth marks are not visible in the photo.

Hey Sander, Thanks for your response. We are using the standard 0.4 mm nozzle and the settings in Cura match. I've tested for nozzle clog even though it didn't seem to match the symptoms (nozzle clog would usually be a random, rather than patterned problem) and filament flows quite easily though the nozzle. No junk came out when I did the Atomic method. We replaced the coupler at the same time as we installed the Olsson block since we had the print head disassembled anyway. After work today I plan to double check the printer has the latest driver versions and check that all of the motor mounts are tight.

All, So a few months ago we had to replace our temperature sensor on the Ultimaker 2, and took that opportunity to install an Olsson block. Did a few quick test prints in Colorfabb XT to ensure everything was hooked up right, then left the printer alone for a few months, being too busy to print. Recently we've returned to perform a few prints but are confounded by a few odd issues we were not having before. When printing I am getting some odd patterning in the walls of the prints, especially near corners. Best example I have is printing Coffin's Cube, one of the default prints on the SD card from Ultimaker. As you can see ~ 4 months ago there was only cosmetic pillowing (while visible to the naked eye, completely smooth to the touch), but in the print I made yesterday it has severe pillowing and an odd pattern in the walls of the print that I've never encountered before. Both blocks were printed using the default G-Code, Temp = 240, Printbed = 70 C, Fans off for first few layers then on full. Same exact settings, same filament. Only difference was they were printed about 4-5 months apart. I've tried newer rolls of the same filament, just in case humidity / water contamination issues were at play (though if they were I would expect to see random problems, not patterned problems) but no change. Playing around with the settings, if I either increase the top layer height to something ridiculous like 1.2 mm, or increase the temperature to 260 the pillowing and patterns begin to go away.... Any ideas? What could have changed in my printer in the last few months to cause this issue? Some problem with the temperature sensor that we replaced? The olsson block? Something else?