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conny_g

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Posts posted by conny_g

  1.  

    Do you need extra beta testers?

     

    ... and to answer @Dim3nsioneer as well.

    We'll see this next week. Some people already have been asked but not everyone might have enough spare time left within the next two weeks. The aim is to have a handfull of people installing it pretty soon.

     

    Excited! Should you need another tester...

    Drive train: does it make sense to simply buy the UM2+ upgrade kit, that has all the parts? (I have a UM2+)

    Seems a bit expensive, but does it get cheaper buying the parts individually?

  2.  

     

     

    I did some testing today and found that grounding ROSC actually made things a bit worse.  Possibly the back EMF is too strong in this mode, causing other issues...

     

    You were testing with UM2? What does worse mean, what happened?

     

    I tested on my UM3.  Grounding all the ROSC pins made some wavy lines appear when printing a circular ring.  On the other hand, when I did this hack on my UM2 last year, it really improved Z-banding.

     

    That's helpful, thanks. Will try this hack/fix! :-)

     

    Implemented the hack this weekend. So far no negative impact in 3D printing. Did not compare systematically if prints are better, so not sure. But my focus there is on the laser exposure, to be tested soon. Definitely the motor sounds are more smooth than before.

  3. Found the answer:

    As the Ultimaker 2 main board bases on the Arduino Mega2560 this part is simply identical.

    The schematics here are almost the same:

    https://www.arduino.cc/en/uploads/Main/arduino-mega2560_R3-sch.pdf

    https://github.com/Ultimaker/Ultimaker2/blob/master/1091_Main_board_v2.1.1_(x1)/Main%20Board%20V2.1.1.pdf

    And for that the firmware is simply the Arduino one for the Atmega16u2 that builds the USB to serial bridge on the Atmega2560:

    https://www.arduino.cc/en/Hacking/DFUProgramming8U2

  4. Hi there,

    a while ago I did some hacking & measuring with the Ultimaker 2 mainboard and likely due to some sort of USB ground loop between laptop / oscilloscope, and the laptop USB connection to the Ultimaker I destroyed the USB port of the UM mainboard (v2.1.4).

    At least since then the USB connection to the board does not work any more.

    Back then I have replaced the board with a new one and the printer works. But I would like to salvage the old board and repair it, if possible.

    I researched the board schema and obviously the USB connection is built with a Atmega16U2.

    My assumption would be that the Atmega or it's USB pins are damaged and I would like to exchange the Atmega and reflash it with the firmware. (There is a fuse before the Atmega, but it seems to be ok, unfortunately - it would be easier to change the fuse.)

    Where can I find the firmware of this Atmega16U2?

    I know where to find the Marlin firmware (customized that already), but could not find the USB firmware yet?

    Regards,

    Conny

  5.  

     

    I did some testing today and found that grounding ROSC actually made things a bit worse.  Possibly the back EMF is too strong in this mode, causing other issues...

     

    You were testing with UM2? What does worse mean, what happened?

     

    I tested on my UM3.  Grounding all the ROSC pins made some wavy lines appear when printing a circular ring.  On the other hand, when I did this hack on my UM2 last year, it really improved Z-banding.

     

    That's helpful, thanks. Will try this hack/fix! :-)

  6. Couldn't help but double check what resolution I was running when I discovered the irregularities.

    Here's an image where I exposed with 1016dpi and the "gap" happens every 8 lines.

    pcb_exposure_1016dpi.thumb.jpeg.6c2aa47320513b60b832c25e2c5e0b71.jpeg

    That would mean the native resolution of 1 step of the UM2 is 2032dpi or 80 steps per mm.

    And yes, that's what I find in the Marlin firmware:

     

    #define DEFAULT_AXIS_STEPS_PER_UNIT   {80.0,80.0,200,282}  // default steps per unit for ultimaker2

     

    So... yes, it's every 16 steps, it is that problem.

    pcb_exposure_1016dpi.thumb.jpeg.6c2aa47320513b60b832c25e2c5e0b71.jpeg

  7. It's easy to ground this pin but also easy to destroy your stepper driver.  Only do this if you or a friend are experienced with working with and soldering SMT.  Someone on the forums destroyed their stepper driver already when they attempted this change.

     

    I have experience soldering.

    Is there any instructions on the web on this, where to fix the PCB? Researched for a few minutes (web+forum) and could not find any?

  8. The decay fix is a fix for an electronics problem. The electrical motor drivers that we are using can be put into different modes of operation. The intention was to have it in a certain mode, which was done by putting a certain pin at 0V. However, this was done with a pull-down which is not strong enough. It causes an inaccuracy every 16 steps.

    This can be fixed with a simple solder bridge over this resistor.

     

    Interesting! I am "misusing" the UM2+ as a laser exposure device for PCBs, by mounting a laser on top (now instead) of the 3D print head and by modifying the firmware slightly to give sync pulses on certain movements (adding a parameter to the G-Code that causes the pulling of the fan output high once that path starts) so that the laser control producing 500-1000dpi pixels can by synced with the movements.

    And I discovered an irregularity pattern in the resulting lines that I assumed to be exactly this, but I thought I had to live with it.

    Attached a photo of a etched PCB that shows thicker and thinner lines (horizontal lines) and oscillating thickness (vertical lines). That's exactly this thing I suppose.

    The print head was going horizontally with constant speed in that case, stepping vertically.

    I think the tracks are in the 5mil range, don't remember exactly.

    So if the resolution of the printer is 1016 dpi (not perfectly sure), 1 step being one dot, then 5mils are 5 steps. Each track + distance 10 steps.

    As it happens ca. every 3 tracks that would be some 30 steps (likely 32 if it's connected to the steps).

    Does that reflect the issue?

    IMG_5846.thumb.JPG.fe9ec51484ae3c3a0589fc609d3602ce.JPGIMG_7516.thumb.JPG.24e1bad56baee1d49114651a9ca6bdab.JPG

    IMG_5846.thumb.JPG.fe9ec51484ae3c3a0589fc609d3602ce.JPG

    IMG_7516.thumb.JPG.24e1bad56baee1d49114651a9ca6bdab.JPG

    • Like 1
  9. It is just about 3 month that I bought an ultimaker 2+ 3D printer, but now I realize that I had to wait.

    I already asked to ultimaker whether they have an update to my printer and the answer was this:

    Sorry! we won't be able to offer an upgrade kit for the Ultimaker 2 series, as too many parts have been changed between the two models.

    How reliable would to add a dual extrusion with ulticretr http://ulti.creatr.it/en/index.html ? Can I invest $500 us for this? what about the price of water soluble PVA?

     

    In my view UltiCreatr are not a reliable company. Sent them email, no response. They stopped posting about their product. Strange. And I have read of difficulties other users have with them. I would not recommend to do business with them.

    • Like 2
  10. I won't stop you from selling your Ultimaker, but I honestly think that it's not worth it......

    Most prints don't have the complexity at which soluble supports is necessary, and the 1k jump in the price is rather large......

    It really depends on what you're using your Ultimaker for. If it's just as a tool you use at home, then I would probably stick with the UM2+ and possibly hack it a bit to get some newer features, but if you're running a company or printing hub with it, the UM3 is a great choice because of the automation and reliability.

    Again, your choice, but I just feel bad for the Ultimaker that you're going to sell.

     

    My 3D printing is maker hobby so far. But I am usually ambitious & perfectionist if I do something. Then I want to achieve the best possible.

    And if there's a solution to dual printing for support material or other fun now, I NEED this :-)

    The price is secondary in that case, I would also be ready to invest 500 Euros in one of the good hacks that were developed recently for dual extrusion. But with all these the tuning work to get them going worries me. None of these upgrades is plug and play, for me that might be worth the +1.000 Euros for the UM3, eliminating this hassle.

    But definitely the 3.500 Euros is the uppermost limit to spend on a personal 3D printer... ;-)

    On the other hand the UM3 is not as hackable any more. (Or better you don't want to mess with that any more, you'd compromise it's reliability).

    I created a exchange head and a hacked firmware for the UM2+ that lets me UV laser expose PCBs, that's slightly harder with UM3, new hardware, new firmware, new print head.

  11. That's because used Ultimakers are not for sale a long time :)

    I would target a price between 1800 and 2000€ for a used UM2+ assuming it's in a good state (which it probably is having only 500 hours)

     

    Makes sense. I thought of some 1500-1750. Bought it for just 2200, so 2000 are a bit high probably :-)

  12. Hi there,

    I am desperate to be able to print with support material. Thinking of selling my UM2+ to buy a UM3.

    What is a reasonable price for a UM2+ purchased in March, having some 500h print time?

    Is there a working market for used 3D printers? To my surprise there are not too many printers on eBay.

    Thanks,

    Conny

  13.  

     

    Hi @dancorrigan,

    Have you see this mod? It is definitely an interesting approach and shows quite some potential :)

     

    Pretty cool. I like the concept. I don't like the loss in Y printing space though. Any idea why Ultimaker chose not to include dual extrusion out-of-the-box for the UM2+ ?

     

    What @Meduza said. It would have involved either very complex modifications to your trustworthy Ultimaker 2(+) with risks or such an expensive upgrade to cover all that, that would be unreasonable to charge. Hence, we did not feel comfortable unleashing that on our community and we felt the user experience was too important to mess around with.

     

    Ultimaker has an "Appe like" attitude: quality before time to market, make sure the device works perfectly well before getting into feature creep.

    I am totally behind that as I am very happy with the reliability and quality of the Ultimaker, which is a result of that attitude.

    Only 1 of 5 prints that I do have some severe issue. And if there is an issue then more due to material change and non-perfect parameters.

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