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Posts posted by Waternut13134

  1. We think we have it!

    While we are still testing to be a 100% sure internally. We've put this change up for installation already as the "Testing version" 3.6.3.

    The only change in this update is the fix for the USB always showing empty file list issue. There is still a 2nd issue, where it shows a empty file list on the first try, and a full list if you press return and open it again. We didn't fix that issue yet (We do know the cause, but due to the easy workaround of closing and opening the menu we didn't spend time on that a fix yet)

    The bug itself.

    Now. If you want to get technical. The cause here is... the glowing of the LED ring at the front of the printer when your print is finished. What? Yes. This ring is glowing by some code on our side, but the LED output is controlled by a linux driver. So we are talking to this driver. Due to changes in how we manage the LEDs, we are updating this LED more times per second then before. A bug in the LED subsystem of linux caused every write we did to this LED ring to cause 3 or 6 "udev" events. This is a general event system from linux for hardware changes. Hardware changes that include USB removal or insertion.

    Now, this LED glow was generating these events faster then they where handled. Creating a backlog. This backlog in turn caused the handler of these events to use a lot of system resources, at which point another system decides at some point that this handler is most likely misbehaving and needs to be restarted. Only increasing the amount work to be done instead of decreasing it.

    Why is this important? Well, because these events where never proper handled anymore, the USB drive removal was never properly handled, and the insertion was also not properly handled anymore. Causing the system to look for the "old" insertion of the USB stick instead of the new one. And thus not being able to read it, it shows no files at all (and the read error never bubbles up to our code)

    Currently we placed a tiny fix in the code to prevent these events, and nothing else. We already had plans to update our linux kernel towards a more stable version. But we didn't want to push out this kernel in a hurry just to fix this bug, at the risk of introducing a different (possibly larger) problem.

    This was one of those, you have to be kidding me right? bugs.

    Now, why didn't we catch this one during testing?

    We didn't catch it at the development team because we clean our printers pretty much as soon as they are done. Our printers get updates multiple times a day, and you need a lengthy session for this bug to happen. Our testing team switched to mainly network printing to better validate the Cura network printing at the time this bug was introduced. So they did notice it once or twice, but didn't get to notice the severity of the problem. And they also had a bad batch of USB drives before, which made them a bit less alert on USB problems and quicker to think "oh, bad USB drive".

    Why in the 3.6?

    Wait you might say! The LED ring was glowing before as well. Yes. It was. But the update was at a lower frequency, reducing the amount of events, giving the system more time to handle them.

    This change was introduced when cleaning up the LED control code during 3.6 development. Before this release the LED control code was pretty much the first prototype we made for this code. It functioned, but when we wanted to add the user configurable lighting, we also cleaned up this code. Introducing this unintentional bug in the process.

    The big thank you

    I want to thank you all for reporting this, and the people that helped in the diagnose both online and offline. It was a tough nut to crack, and really every tiny bit of information helped here.


    Glad to hear its been found. So is the testing version pretty stable then? Just contains the fixed code? Thanks!

  2. It happens to me every time I unplug the USB drive.

    I used the USB drive that came with my UM3, Sandisk 4GB,Sandisk 8GB,a USB memory card reader that had a old 256 MicroSD card,8GB and 16GB memory cards.

    The dump Files wont write to the USB drives, It throws up some sort of error,If you power cycle the machine where it can see the USB drives it will write the dump files just fine.

  3. David, Im having the same problem as well. I got my printer like 2 weeks after launch and didnt touch the firmware after that so I had what ever came on the printer.

    Ive tried a few things, it seems like after every print if I remove the USB drive and put it back in the UM3 will not see it. This goes for every drive I have tested so far. (5 to be exact) I have reformatted the drives as well and still have the same issue. Now one thing I did notice is I have a USB memory card ready, I placed a file on the SD card and placed the USB drive in the printer and the printer sees it, Now if I keep the drive plugged in but remove the SD card and go to a print a file the UM3 still shows all the files that were on the SD card even though its not plugged in. I dont believe the old firmware version did this. I dont know if that will help or not but figured I would mention it.

  4. I came here wanting to say after the firmware update,If I unplug the USB drive to load new files on it and then plug the drive back into the UM3 it will display nothing but "Return" I have to turn off and back on the UM3 again to get it to see the thumb drive again. Ive tried 3 thumb drives so far,All have the same problem.

  5. Well I tried a factory restart as I lost connection on wired as well,The UM3 said it was restarting and the screen just went blank and the lights stayed on,I left it like that for about 1 hour and went ahead and turned the machine off and back on again,Now nothing!!!!! I hear 2 clicks under the machine and nothing,No lights or anything,The only light that is on is the little red light under the machine. Any thoughts? =(

  6. So ive run into a weird issue,When I went to cura to send a print over wifi I noticed it didnt see my UM3. So I checked the status on the connection on the printer and didnt see an IP address or anything. So when I go an try to rerun the wifi set up it just sits at creating a wifi hotspot,And I mean it sat for over an hour doing this,When I cancel it just defaults back to LAN,I have tried running an ethernet cable to the printer and it instantly pulls an IP address so I believe it has something to do with the WIFI Module? However I prefer wireless as I currently am running a 150FT ethernet cable across the house lol I have unplugged the system and router/modem to not success. Any ideas on whats going on? Thanks!

  7. The black piece that is attached to the printer,Take it off and assemble it with the piece you have to the left of the picture. (Basically you want this all assembled). Now as 1 piece put the screws through the holes and attach it to the stepper motor. It will make it a whole lot easier if you take the white metal cover that covers the stepper motor so you can align the screws better.

    Edit: after looking at the pieces I believe you put the parts in the wrong case. Try putting them in the case that is currently connected to the printer.



  8. You could:

    - In Cura 15, there is a setting Advanced/Initial Layer Line Width, which can do what you are suggesting, by reducing extrusion on the first layer.

    - Chamfer the bottom edges of the model, i.e. a slight undercut to compensate and give a nice smooth edge instead of a sharp edge around the bottom.

    - Lower the build platform slightly - try 1/8 turn of each leveling screw,


    Thanks for the tip. Im using Cura 2.3.1 which I got off of UM site, I cant seem to find the Advance Initial Line Width. I even tried searching for it and I can only see Initial Line Speed. Am I missing something? Thanks

  9. Hi all, I just got my UM3 yesterday and love it,However I am getting way over extrusion on my first layer. Is there a setting in cura that I can mess with the multiplier for the first layer? Ive always used S3D so im brand new to Cura and learning it as I go. Right now im messing with the flow settings but I know that will mess up the model after the first layer. Thanks for any help.

  10. Ok so I may have posted that update to early!

    How long have I had this printer? Not long. Two days is it, something like that.

    I've only printed during the evening in those two days and now this...


    So do I get another one? I thought it was supposed to be third time lucky. Maybe its fourth or fifth tho.

    I'm not the only one having this problem.

    This is getting to be too much!!!


    You may want to contact your reseller for a replacement. In the meantime I believe a file for the axis holder is on Youmagine that you can print and should tide you over in the meantime.

  11. I just got my UM3 today and I hear the ticks as well. Like Erin said I believe it could be the XY axis. I noticed the default print speed in cura for UM3 was much faster than what I use from S3D,Once I turned the speed down I noticed the noise stop. Maybe try slowing down the speed a bit to see if that helps?

  12. I figured it out! So after thinking I didnt make the connection right under the printer I kept taking it plugging and unplugging and still nothing,So I decided to take apart the spool holder and what do you know the connection to the NFC reader was barely connected. Now it reads like a charm =)

  13. So I just got my UM3 and so far everything seems to be working great. However my UM3 cant recognized any filament. I checked the connection for the NFC reader and everything and it still cant see the rolls of UM filament that I installed. Any suggestions? I know I read someone else had the problem as well. Thanks

  14. Ive had this issue,Are you using a Mac? My problem was when ejecting the SD card from the Mac,Some how the card got corrupted and would cause my UM to go nuts on some prints and even stop in the middle of a print. This was happening to files that I had successfully printed a number of times before. I filed a bug report with Apple and they found the issue and said it should be fixed.

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