gr5

I'm not sure if this is correct but I think if you have 2 versions of cura sometimes they interact? Usually not - I mean I have a few versions and it's fine but still - maybe delete everything (includes all profiles and every profile or setting change or machine you installed) in the configuration folders. I think probably here: ~/.local/share/cura/master

@ahoeben or @ctbeke have ideas?

Another thing to try if it shows the holes in preview mode also is to change your line width to be slightly smaller. For example if it's currently 0.4mm try 0.35mm.

I'd just try reprinting it at half speed - in settings in cura search for "speed" and leave the travel speed alone but set all the printing speeds to be the same value and try nice and slow such as 25mm/sec. If that doesn't fix it then install this version of cura that is better at thin walls. MUCH better: https://github.com/smartavionics/Cura/releases I'm not sure if it has built in support for Ender. It probably does if regular cura does as smartAvionics keeps pulling the latest version of Cura into his version and merging so it has good thin walls *and* it's updated regularly.

Done! Thanks.

I'd try flipping the part over and printing without support but it might fail at the end. It depends how much you care about the quality of how this looks. And if you want the ugly support removal marks to be inside or outside the part.

To make your part stick better you can turn support back on for "support placement" make sure it's only for "touching buildplate". Also mess with the angle that will get sukpport - maybe set it to 70 or 80.

Make sure you are in PREVIEW mode (one of the 3 display modes across the top). Then just below that choose "color scheme" to be "line type" and make sure "helpers" is checked.

If cura crashes on startup you can locate the cura log file and post it. Even better, once you know where the configuration files are stored (2 different folders) you can delete everything in those folders and restart cura and it may just work. I don't know where they go on a mac. Someone with a mac can do "help" "show configuration folder" and let us know. log file location On my windows10 computer it is here: C:\Users\gr5\AppData\Roaming\cura\4.8 On linux is here: /home/gr5/.local/share/cura/master

Nice! That's great news.

By the way, this is the exact reason "z hop when retracted" is disabled for 99% of printers - only delta printers or printers with a z axis that comes back to the exact same spot every time can use that feature. I tried z hop once and got the same results you did.

It looks more like a Z issue - I've seen this 100 times where the Z axis doesn't move evenly. However you are right - it only appears on the layers with retraction. Also are you sure they are only undeextrusions? Some look like over extrusions. The one thing that would explain everything is if you have "z hop when retracted" turned on. Or maybe it's this "missing outer walls" thing that I've absolutely never heard of. You'll have to show what you mean in PREVIEW mode - make sure "color scheme" is set to "line type" so I can see what you mean by "missing outside walls".

I have Ubuntu Linux. Works fine for me. I do get a handful of errors like you but it seems to work fine. The key error is the "segmentation fault". I definitely don't get that! Anyway please post the cura log file which will likely have much more information. For me it's in: /home/gr5/.local/share/cura/master There are software people who work on cura on this forum and with the log file they will know much more. Is your Linux 64bit? I think that's a requirement. Also you need to have an x86 processor (intel or AMD). Not some cell phone chip or something. Not a chrome pad.

Yes. People post their cura files here all the time from "obscure" printers (ones I don't have) and when I load there project file I see their printer (machine) settings and that is in my cura going forwards - until I upgrade Cura I suppose. I have a Linux machine but most people use Cura on PC or Mac. It makes no difference. I got burned a few times with profiles (years ago) and once I discovered project files I stopped using profiles. Years ago.

Startup the older "good" cura. Slice a model with the right settings. Then do menu "File" "Save...". This creates a project file with your machine (printer) settings, your profile settings, and your overrides to the profile. It also saves your model(s) and orientations and other things. Then exit cura, open the newer cura and open that project file. It should have everything perfect with the machine setup. It will even add the machine to your list of machines available. I don't use profiles. I use project files. Whenever I go to slice something I think "what did I slice that was similar - oh yeah - that nylon lens holder" I then start with the project file for that similar item, discard the models and drop in the new model. Also of course whenever I save a gcode file I also save the project. It's just a reflex now - I don't think about it.

I don't understand leveling on the UM2+C so my earlier comments about that can be ignored. However since you want the bed *farther* from the nozzle this is kind of easy. Maybe. You want to reset Z=0 so you want to add these gcodes *after* it homes. Homing commands are G28. For example G28 Z0. Or just plain "G28". Somewhere after that - maybe immediately - do this: G0 Z2.00 G92 Z0 The first command moves the bed up until it is 2mm above bed (according to where it thinks is the bed which of course is about 2mm off). The second command (G92) resets the coordinates (for Z axis only in this case) such that we are now officially at Z=0 (which used to be thought of as Z=2). You can adjust the 2.00 to other values until you get it perfect. I don't know how you would redo leveling but foruntatly the hardware should keep a consistent level for months. The pain in the neck is adding these 2 gcodes into every gcode file. You can do that with a plugin that you could write (there are very simple examples to start with in python) or possibly with editing the "start gcodes" in the machine settings (probably you can't do that). Come to think of it - it's possible that there might not even be a G28 in the gcode as it may be automated before it gets to the gcode (along with nozzle purge possibly?). In which case you would put the above codes at the very start.

I'm saying when you are in PREVIEW and PREPARE modes (across the top) you can zoom in somewhat on a troubled spot and take a screen shot and post it. I've never used an obj file - I've never had problems with an STL unless it had say millions of triangles in it (but obj can have the same issue most likely). So anyway, please post the project file. That will have your part file inside of it so we can see that. It will also have your placement of the objects on the bed - any rotations, scaling, merging, etc will be shown. Also it will have your machine settings (aka printer settings) and your cura settings. ALL preserved into one file so we can see exactly what you see when you slice.

Tinkercad is one of the good CADs if I remember right in that it is good at creating manifold objects. Hopefully you remerged that S before saving as STL, right? If you can't get the project file figured out (or in addition), it might be helpful to see your part in PREPARE view (and PREVIEW) as well - showing the issue.

To create a project file (extension is 3mf but don't call it that please as cura creates other types of 3mf files) do "file" "save..." from the menu.

So the method that is the least work is to buy a new olimex board from fbrc8.com: https://fbrc8.com/products/olimex-board-um3?_pos=17&_sid=b05a8a086&_ss=r It's also the most expensive method and not the fastest as you have to wait for shipping. The fastest and almost as quick method is to "unbrick" it using a micro SD card. You may already have one in a gopro or cell phone or other device. Or you can order one cheap on amazon. If the printer was in developer mode (you have to switch to developer mode which I did in the first week I had the printer and it's been that way since) then you can try to ssh to the printer. Tricky since you'll have to try to figure out the ip addres e.g. from a router or using a port scanner. But there's a strong chance (>80%) that it is crashed before it started the ssh daemon. Anyway if ssh works you can use linux commands to investigate the log file. The os is "debian jessie". Likely a file is corrupt and needs replacing anyway. If it were me I would start with the micro-sd card unbricking method. Ideally call your reseller for instructions on unbricking. The file that you need keeps changing and moving around. I can post one for you if you are desparate. But that shouldn't be an issue for you - if the reseller won't help, email support@fbrc8.com (usa customers only!) and send them you serial number and ask for the micro-sd restoration procedure. I think they have a pdf of instructions. If the unbricking method doesn't work and you don't want to spend the $371 then you can get an olimex-serial-F cable from my store (again, USA only) at thegr5store.com and then contact me for instructions how to connect it and watch the unbricking in progress and see where it gets stuck. I've helped two people reformat their flash drive (built into the olimex). Unfortunately the unbricking procedure doesn't do this automatically. I have extensive notes on how to do the reformatting and sometimes it doesn't work because the flash is just too damaged and even the reformat fails. This procedure takes a few hours typically (lots of steps). So if you would rather not waste several hours the $371 might be the better option.

Can't you just turn the 3 screws the other way for quite a while and start over with the manual leveling?

I don't have a UM2+C and have never touched one. I know a few who have one but that's no substitute. I do have the S5. #2 - yes - very slow boot. Just like UM S5 and S3. It's booting Linux - a very advanced operating system. Similar to Windows but on a slower cell-phone-like processor. This is normal. 1,4,5,6 - The feature set is quite small compared to the UM2 series printers. I think this is on purpose. They will probably add a few features but unlikely these 4 (I guess they are most likely to fix the #3 bug). I love my um2go so I got 3 of them (and added heated beds). The UM2+C I think is aimed at non-experts. Because you are an expert I would have predicted you would be dissapointed about many of the features. It's also aimed at print farms where you have many printers and you want them all to work the same way so you can queue up prints and schedule prints and such "on the cloud". Unlike the S5, the UM2+C doesn't allow you to ssh into it. That is absolutely a "not interested in this printer" feature for me. With the S5 I can ssh in and I have the full power of linux including an immense selection of network tools and settings that go beyond a MAC or PC even (e.g. mesh networks maybe?). On the S5 you can configure wifi and ethernet to no end. Hopefully someone more knowledgable will answer your questions.

PLEASE USE ENGLISH IN THIS TOPIC! NO ITALIAN. NO FRENCH. There is a french group. And an italian group (I think). Otherwise, in this group, please use english. For example you can use google translate. Thank you.

oh. Yeah a picture is worth a thousand words.

I mostly do mechanical things and no matter how good the scanner is (one billionth of a meter accuracy) the model is going to have errors and weirdnesses that will annoy the slicer slightly. For example the bottom might be flat. So I always redesign parts from scratch. I use a micrometer. Some people do a scan and then pull it into CAD and on a different "layer" they create the same model from scratch but they can visually line it up with the scan. For art pieces like sculptures, a scanner is desired.