gr5

Oh - to fix #1 you can print the walls *before* the infill. Or you can probably just print the outer wall first. Both are possible to do in Cura settings.

That diagonal pattern can have a few causes. 1) First to check is print through from infill. Look at the part in Cura and see if those lines are over where the infill joins the part. 2) Second to check is stepper issues but those wouldn't be diagonal unless your wall on that cube wasn't vertical. Is it possible the wall tilted out a bit? And was the cube rotated on the bed a little bit also? If so then we can talk about how to fix this. I'm betting it's #1.

I really like Cura 15.X a lot. It's from 2015 and usually gives me better quality prints than Cura 4.X. I don't know why. But mostly I use Cura 4.X. Cura 15 is simpler to learn as it has many fewer features and it just works real well. It's had something like 5 years of debugging. But I need Cura 4.X for my newer printers and so tend to use it for everything.

To be clear - you put the M104 and the M140 before the G28? it looks like you put the M190 before the G28 and of course that won't work. The two gcodes with the "4" in them get things started but keep running to the next command (e.g. G28 - home). The codes with the "9" in them should be after the G28. They tell the printer to not proceed to the next gcode until they are completely done. If you did it right (put the "4" commands before the G28 and the "9" commands after) then it's something about your printer's firmware and you should talk to people with the same printer.

If you don't mind we'll leave this up in case anyone else has the exact same question. Note that in cura, in PREVIEW mode make sure moves are visible (checkbox) in "color scheme: line type"and there are 2 shades of blue. Blue moves are non-extruding moves. One shade is for retraction moves. That's a really good way to tell which are which very quickly. The rules for if a retraction happens is complicated so it's good that Cura shows you which are which.

no - there is no % control on the 20 or so speeds. If the print speed in cura is 60mm/sec and you slow down to 50% it is exactly the same as if the print speed had been 30mm/sec in Cura. Sort of. Not exactly because... There are many print speeds in Cura. From memory, 7 printing speeds, 2 travel speeds, and even retraction speeds. If you lower ALL the speeds in Cura including retraction speed... ALL of them - by 60% then that is the same as setting the print speed to 60% in the TUNE menu of your printer (regardless who makes the printer). In reality you shouldn't have to lower all the speeds. Usually you get better quality with fast travel speeds (less stinging, less bumps, less underextrusion after a travel). What is the symptom where you like your prints better when you print slower?

There's 2 ribbon cables that go to the screen. There are 8 ways to connect them I think. (two ways each cable and reverse connectors). Are you sure you have them connected correclty? Also inside the ulticontroller - if you take it apart (or maybe access through a hole) is a potentiometer that you can turn with a screwdriver. That's a 10 turn pot I think. Turn that many times in one way and then the other. It's possible there is an invisible message and it's actually working already.

On pronterface you have to select the com port (com5). You have to make sure cura isn't running as it may grab com5. And you have to set the baud rate which I think is 115,000 (roughly) baud. Then I think you hit a connect button or something. If it works you will see a stream of gcode listing the settings of the umo printer (like steps/mm and max speed and max acceleration). Anyway - since you have the ulticontroller I strongly recommend not using USB cable and using only SD card which slides into the ulticontroller. Put the gcode file onto the card and put the card into the printer. That way a windows update, or sleep screen (or 100 other similar issues on windows) won't crash your print.

If this is a new printer for you or if you updated the firmware in the last 6 months then you can try "reset to factory settings". It fixes a whole ton of things when you do that but you will have to level the bed after. Also if you adjusted the filament settings then those changes you made will get lost. But "reset to factory settings" is pretty harmless other than that. On many firmware installs you don't have a choice. Also I recommend tinker firmware (which will also require a reset to factory settings after). If you haven't been messing with extrusion rates/flow rates on your printer then that's probably your best next step: https://github.com/TinkerGnome/Ultimaker2Marlin I have tinkermarlin on all 3 of my um2go printers. I don't use Cura 4.6 yet - I'm on 4.0 I think but it's not much different. I strongly doubt a bug was introduced between 4.0 and 4.6.

One possible cause is if you mess with the flow. Did you set the flow on your printer to anything other than 100%? If so there is this bug in the Marlin firmware on the um2go - it's internally translating all the E values so it might get E1000 and if flow is 90% then ever since E was zero then it does E900 but if you changed flow part way through it has to do even more math. At the very end it does a *relative* move I think in the gcode and it retracts. But it gets confused and thinks it's at say E900 when it's really at E1000 and it retracts (or unretracts) like 100mm of filament. Or it tries to. And this takes a few seconds. And it melts a big hold in the print.

By the way - if you are going to be doing all this you need a recovery plan in case you brick linux. You can do this with a micro SD card install. Your local reseller can help you with that. Or you can actually connect directly to the linux box with a serial cable. That way if you break something that keeps the install from getting past the ssh daemon you can still connect to your machine. I sell the cables here. Keep in mind that this is kind of advanced stuff if you are new to linux and serial terminals and such. The microSD card is a simpler solution but it resets everything back to factory install when you might just need to delete a single semicolon or something: https://thegr5store.com/store/index.php/catalogsearch/result/?q=olimex

And I don't use wifi on my UM3. Your community keeps shrinking. Sorry! I know from experience that the firmware is complicated - or more accurately - there's a lot there. An overwhelming amount of code. And this issue looks like a difficult one to fix - I'm guessing some kind of memory overflow/stack overflow versus a simple bug. Memory issues are really hard to track down. And usually not easily repeatable. The only thing I might try if I were you is replacing conman with the version they put in github. Or trying to get the latest version for the installed operating system. I don't know how to do that exactly (apt get??). But a lot of googling and a lot of reading might help you update conman to the latest version meant for this particular flavor of linux. In another thread on this forum, recently (in the year 2020), is a discussion of updating certain aspects of linux on the UM3 (or possibly S3 or S5 - it's all the same). The guy updated some parts of linux and it helped some issue he had. Probably network related. So you might want to do a google search for that thread. Definitely use google with "site:ultimaker.com" as part of the search and restrict to posts in the last 6 months. That guy seemed quite knowledgeable and what he said would give you a huge start on how to update the linux on your um3.

Are you all set? did you find machine settings okay?

You are doing great so far. It's visible on COM5 so that's critical. Note that many applications might tie up this port and only one can use COM5 at a time. is it possible you launched other software (e.g. a second version of cura)? 1) Do you have an ulticontroller on your UMO? It's a display that shows a few (4?) lines of text and has a knob to go through the menus. If so then you are better off using the SD card. Save your gcode files sliced on cura to SD and then print with SD. 2) For communication between a computer and a UMO, Cura is minimal. It has the absolute minimum of features and capabilities as none of the currently sold UM printers use this feature. So instead, if you don't have an SD card on your UMO, I recommend using printrun/prontrface. It's free and full featured and MUCH better at seeing obscure COM ports (e.g. I don't think cura will acknowledge COM11 but pronterface will): printrun/pronterface/prontrface download: http://koti.kapsi.fi/~kliment/printrun/

Do you use 1.75mm filament or 3mm filament?

Oh! I saw this a year or 2 ago. Haven't seen it for a while. What version firmware on UM2go and what version of cura are you using? I forget what causes this.

No need to copy to USB flash drive. You can use scp to copy the whole directory structure directly to your primary computer. I guess copying to USB should be easy enough. Use "df" command to list all "disks". One of those should be the USB flash drive. I never tried this but it should work. Use google to find linux commands to copy entire directory trees. scp on your main pc can copy a whole directory tree to your current computer. Syntax is like this: scp root@192.168.1.47:/some/folder/paths/ . It will prompt for root password.

@chase_c - first know that this is rare. My UM3 doesn't do this but that means nothing as I don't use wifi. There are lots of people out there that don't have this problem. Including all the UM3s at Ultimaker I'm sure. All related code is in python and is visible. Or it is part of the linux operating system. Put your UM3 in "developer mode" and you can ssh to the printer. Username "root" password "ultimaker". Are you familiar with ssh? Are you familiar with linux? You can google about wifi settings. You can update the wifi driver (but that will get lost the next time you update UM3 firmware). The problem may however be in the python code somewhere. Python code is not compiled. It's all visible. Comments and code and everything is all visible. Unfortunately the firmware is not published on github so you can't see recent and proposed changes. That's too bad. Cura is completely open source and you can see what features are coming out and developer's thoughts on various bugs but this doesn't exist for UM3/S3/S5. There is this one sub part of the UM3 firmware though which might be related? https://github.com/Ultimaker/connman/issues (conman is related to network settings and wifi)

I think the "reset to factory" did it. I doubt it's the core as the core wasn't even touching the glass. It can be the core (sometimes the spring in the core is too weak). But it never even tried to compress the core.

You don't enter the layer actually - you enter the Z height - the Z position - of where to continue the print.

I'd get a uninterruptable power supply. So you will need 2 of the features that come with tinkerMarlin. I mentioned above - you can set the Z position of the print head exactly. In this mode you spin the dial until the nozzle perfectly lines up with the last good layer and you look at the display and it tells you exactly the position of the head. You want the print to continue on the next layer. You will have an ugly transition. If you are off by one layer then it will either over extrude or underextrude. Even if you get it perfectly the top layer may be only half done. But it works pretty well. I've done it.

I'd do a quick clean with a paper towel. Have one person slide the cross bar up and down and the other stick the paper towel into each thread (remember triple helix). Use a long thumbnail or something to get the paper towel in there. However I think the issue is probably something else. Maybe there was a filament tangle. But then wasn't the overextrusion on the very next layers? If so then it's probably Z.

Are the two problems near each other? I think the Z movement is causing both problems. If it moves too far you get the gap, if it moves too small you get the overextrusion. Overextrusion is the most rare of issues in 3d printing. Not much can cause that. Wait - I looked at a photo of the ender 3 and the nozzle is moving up and down in Z - not the bed. Z is vertical. Maybe you thought I meant Y. So I don't understand. How could the nozzle move too far upwards suddenly? Maybe dirt could do this on the Z screw? Is this PLA? I've seen layers that get this gap but only in higher temp materials like ABS, PETG, Nylon, PC. Never in PLA.

You could try putting a brick or something on the bed so that it moves down more consistently (again I'm guessing this printer moves the bed up and down and not the nozzle). But usually the proper fix is to clean the z screw.

The gap is some kind of underextrusion and because you show the "crowded" layers above the gap that tells me a lot! Most likely the bed kind of "fell" suddenly (is it a printer where the bed moves? Or the nozzle? what kind of printer is it?) which is why you got that gap - an underextruded layer. Then the bed to nozzle distance moves too small an amount for several layers and you get overextruding (what you called "crowding") for a few layers until things are caught up or back to normal. If you have some kind of Z screw (or screws) moving the bed up and down then that would make sense for this error. Try cleaning the Z screw. Usually they are triple helix so get all the threads. Concentrate on the height where this happened.