Morgan Build, Ann Arbor MI (US)

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    • #560
      knarfishness
      Participant

      Hey Folks,

      Made some good progress this last week putting together the frame for my Morgan. I’m converting my spare Prusa Mendel v2, so my hunt for parts has been pretty minimal. (Still need to come up with 6805 bearings).

      I’m using aluminum pipe instead of the recommended brass (or copper) as it was a bit cheaper in my area. Most of my “SAE Conversion” has been done with a Dremel tool, so far as the tube fitting is concerned.

      Anywho, I’ll update with questions/progress pics as I go:

      https://www.dropbox.com/s/ogxjhhsc326waz4/2013-07-10%2001.34.25.jpg

      -Frank

    • #561
      Quentin Harley
      Keymaster

      Good progress! Let me know how those Alu pipes work.

    • #568
      Quentin Harley
      Keymaster

      6805 is a bearing commonly used in bicycles, and if you go to your local bike shop you will find it as hub bearings. Get the cheapest ones – the ceramics are great, but too expensive for the use!

    • #570
      knarfishness
      Participant

      Aah, bicycles! That should make them easy to source.

      I’m curious if you’ve experienced any differences in the bowden tube setup between 1.75mm and 3mm filament. I’ve got both hot end options available.

    • #574
      Quentin Harley
      Keymaster

      Only used 3mm on Morgan so far. To all accounts 1.75 works better for bowden, but I have 3mm down to an art now.

      Next machine will be 1.75. Building it right now…

    • #605
      knarfishness
      Participant

      Updates!

      https://www.dropbox.com/s/1znrf9ikl48bxu8/2013-07-15%2022.24.39.jpg

      I’ve received my 6805s, so I figured it was time to go ahead and prep the frame.

      PVC is painted black now, as well as the oak frame stained a nice reddish color to class it up a bit.

      One thing I did notice during assembly is that the top/bottom mounts for the smooth rod seem to be a bit more narrow than the distance between the bearings that hold the print bed. For now I’ve just cut the parts to get the fit right, and then I can expand the mounts at the top/bottom if need be. Any idea why that is?

      Thanks for looking 🙂

      -Frank

    • #607
      Quentin Harley
      Keymaster

      Looking good. What was the distance on the brackets? And on the Z-bed bracket? I might have made a typo in Openscad when I recently fixed up all the parts.

    • #608
      knarfishness
      Participant

      I’ll double check with the calipers when I get back to my workshop, but I can’t imagine they’re more than a centimeter off on either side (2cm overall missing width on the top/bottom brackets).

    • #609
      Quentin Harley
      Keymaster

      On Morgan master it should be 175mm between the rods. Di you go for 8mm or 12mm rods? 12mm is 195mm between the rods.

      Morgan lite is 160mm.

    • #610
      knarfishness
      Participant

      8mm rods and bearing were what I had left over from the Prusa V2. I can double check my logs to make sure I printed an entire 8mm set, but the large bracket is definitely the smaller one.

      Although looking at those numbers, it looks like the discrepancy that I’m seeing…more double checking required. 🙂

    • #653
      knarfishness
      Participant

      After some checking, it seems that the version of the 8mm top/bottom z brackets came out too short. They can’t be the 12’s, just judging by the holes. That being said, if you’ve got a level, those pieces work just as well as 3 separate parts.

      Little more progress this week (it’s been busy), but the drive system is in place and ready to be belted up. Time to start messing with Marlin and the PrintrBoard.

      [video src="https://www.dropbox.com/s/v8cz9m2ivkvuq87/2013-07-18_22%3A54%3A057.mp4" /]

    • #660
      Quentin Harley
      Keymaster

      Really starting to come together!

    • #693
      knarfishness
      Participant

      Well, I’ve got the first powered movements done. (Almost wrecked it ><)

      Anywho, I’m at the point where I need to mount endstops, but I can’t see clearly in the videos you have up where you have them placed. Any tips?

      Thanks!

      -Frank

      https://www.dropbox.com/s/co78cj83rcp5lw5/20130723_181902.jpg

    • #695
      Quentin Harley
      Keymaster

      End stops

      Hope it helps…

    • #710
      Quentin Harley
      Keymaster

      I found the problem…

      The Z-mount bracket was the wrong type. I omitted to upload the 8mm version of the bracket.

      So sorry! The files are now corrected on the Git repository.

    • #712
      knarfishness
      Participant

      Aah, gotcha. Sticking with my split pieces for now, as the frame is already together, but if I do a teardown after first tests I’ll get them replaced.

      I took a look at the endstop placement picture you sent me as well. I see the placement (but no endstops?) in the pic, and I have my mechanical endstops attached there.

      A few questions moving forward:

      1. What on the wheel triggers the endstop? My best idea was to use thumbtacks/nails pushed into the wheels to push up against it.

      2. Where is the home location supposed to be (in relation to the print bed)?

      3. Home-X and Home-Y seem to operate both motors simultaneously, a feature of the SCARA firmware I’m assuming. However, it seems that once homed, the already homed wheel will start to turn _again_ blowing past the endstop and causing it to go a bit crazy. Is one always supposed to home before the other?

      Thanks a ton for the assistance, I can’t wait to get printing with this thing. 🙂

      -Frank

    • #713
      Quentin Harley
      Keymaster

      The small magnets fits in the hole in the wheel closest to the homing position. The exact position is not critical, because calibration of the end stop homing offset will take care of that – it only needs to be outside the normal operational range.

      I am going to make a small video to make it a bit more clear.

    • #714
      knarfishness
      Participant

      Aah, I’ve never used the magnetic endstop setup before, I’ll have to look into that. There isn’t a firmware setting in marlin that specifies different homing patterns for mechanical and hall endstops, is there?

      Looking forward to more videos.

    • #715
      Quentin Harley
      Keymaster

      😉

    • #717
      knarfishness
      Participant

      Looks like it’s still marked as private. Thanks for taking the time to video it!

    • #718
      Quentin Harley
      Keymaster

      Try it now?

    • #719
      jade39339
      Participant

      Great video, that helped me alot to understand what was going on!

    • #720
      knarfishness
      Participant

      Perfect, gotta love youtube.

      I’ll have to hunt around for a few hall effect sensors this weekend in order to replace the mechanical ones that I currently have. Still not sure why the mechanical ones would act differently, but that’s a mystery for later.

      What I’m curious about now is that the bed homes to the bottom and not the top. I’m still using the threaded rod setup for Z and not the leadscrew, and it seems to me like it would take quite a while for it to come all the way up to start a print.

      Thanks again.

      -Frank

    • #721
      Quentin Harley
      Keymaster

      It doers take a while, but remember that the steps per mm would be greater with threaded rod. You should also use lower microstepping, perhaps 1/4 or 1/8 in order to prevent absurdly high step rates.

      Do not look for a leadscrew yet though… there might be a upgrade in the future that could optionally remove the need for a lead screw, but a lead screw might be slightly more reliable. So if you have a lead screw already, you need not worry that you wasted your money.

    • #722
      Quentin Harley
      Keymaster

      PS: On the mechanical switches, you can make it work if you can make the switch region larger. It should not be easy for it to miss the landing spot.

      In order to save myself a lot of stress, I first simulated the homing routine by hand, monitoring the limit sensors using the gcode M119. This way you can double check that the machine is indeed switching the limits.

      Also remember that they should be wired as “MAX” limits, not min if the hardware has a distinction.

    • #789
      knarfishness
      Participant

      Alrighty, more updates!

      After discovering that I had X and Y reversed (*facepalm*), I’ve got homing working with my shiny new hall effect sensors. Way cooler than mechanical endstops.

      I tried a few dry runs earlier, but it seems like it’s still trying to print right on top of the shaft, so I think that some offset adjustment is in my future.

      -F

    • #790
      Quentin Harley
      Keymaster

      Good. I think it is time for the calibration video.

    • #791
      florent
      Participant

      Can I ask something that might be a silly question ? Surely it’s because my english is poor, but I can’t find a difference, looking on google, between a threaded rod and a lead screw. Do they differ just by the level of accuracy ? Or is there more than this ?

    • #792
      jade39339
      Participant

      Threaded rods are not as I understand it uniformly accurate with regards to the pitch of the screw where as lead screws more or less guarantee uniform pitch, diameter, etc… within a given tolerance range. That’s why they cost much more than a threaded rod.

    • #793
      florent
      Participant

      OK ! Thanks a lot !

    • #794
      Quentin Harley
      Keymaster

      That is correct. Threaded rods were designed to fasten stuff together. Is was never meant to be accurate.

    • #795
      Quentin Harley
      Keymaster

      Right. I took the video, but this one I will have to edit together since I used screencapture and my phone to demo the calibration.

      Give a me a day or two…

    • #796
      Fig
      Participant

      Hi Frank, good job!
      I’ve never used magnetic endstops either, I have no idea what type and where can I buy them…Could you give me a website link of the supplier in order I can buy them directly.
      And is there any calibration of Marlin firmware(Quentin’s armlevel) after mounting them on machine?
      Thanks

    • #797
      Quentin Harley
      Keymaster

      Hi Fig,

      There is a calibration routine, but homing will work even without calibration. I have shot some video a few hours ago, and need to edit it together.

      I am also going to make a calibration flowchart to make it very clear.

      Cheers,
      Q

    • #798
      Fig
      Participant

      Thank you Quentin!
      Awaiting for your nice video.
      I’ve assembled arms, drive wheels and frame, but I don’t know where to buy the hall effect sensors. I searched them on ebay, but that seems different from your video shows… So, could you give me a hall effect sensor supplier’s link?

    • #799
      knarfishness
      Participant

      I snagged my hall effect sensors on Amazon for a pretty decent price:

      http://www.amazon.com/gp/product/B00B67DTM2/ref=oh_details_o05_s00_i00?ie=UTF8&psc=1

      They work well with those tiny ‘thumbtack’ fridge magnets.

    • #801
      knarfishness
      Participant

      Hooray for Friday free-time, I now have a build log, with pics!

      http://dieselpoweredrobotics.com/?page_id=184

      I’ll link this from the first post as well, so people see it. Hopefully after calibration I can get the finishing shots.

    • #811
      Quentin Harley
      Keymaster

      Get your arms calibrated…

      Morgan arm calibration guide

    • #843
      knarfishness
      Participant

      Working my way through the flowchart, but I haven’t had too much time lately. I’ll let you know how it goes when I get done.

      Thanks again.

    • #848
      Fig
      Participant

      Hi Frank,
      I bought hall effect sensors on Amazon, the type is same as yours. But they didn’t work fine, I linked them to RAMPS by wires directly, was I wrong? Do sensors need another electronic board?
      Fig

    • #849
      Quentin Harley
      Keymaster

      Hi Fig,

      Two things to remember when using the hall sensors:

    • make sure it is wired correctly. Do a test on a piece of breadboard first if you are unsure
    • The sensors are polar, meaning that it will not tigger if the magnets are out into the wheels with the wrong pole facing the hall sensor.
    • Hope this helps.

  • #853
    Fig
    Participant
  • #856
    Quentin Harley
    Keymaster

    The sensor should work as is. I use the updated sensor in my machine though… A1101E

    Mine switches at 100G, whereas the 3144 is not clear… The datasheet does not give proper switching values for it.

    I would recommend getting A1104e hall effects. They are very cheap, and work a charm.

  • #861
    knarfishness
    Participant

    Hrmm, just started messing with Morgan calibration again, and my board isn’t responding to M360, M361, M362. G28 to home still works fine. Any idea what’s up?

  • #864
    Quentin Harley
    Keymaster

    All movement in disabled until you hit home, but I assume you have done that first.

    You are running the latest version of qharley/Marlin armlevel branch, right? What does the firmware report when you connect to Morgan in Pronterface?

  • #872
    knarfishness
    Participant

    Yeah, the homing works fine, it’s just the second time I went to run this calibration, it doesn’t respond to M360/1/2.

    It’s reporting fine via the console as well, as the SCARA version of Marlin.

  • #873
    Quentin Harley
    Keymaster

    Sounds weird.

    Which electronics are you using again?

    I just performed the whole calibration routine again after I had to take apart the Daughter of Morgan.

  • #879
    Quentin Harley
    Keymaster

    Grab a fresh copy of the Morgan firmware (armlevel branch) and reprogram your board. When startin up it should state :
    Author: (qharley, Morgan SCARA armlevel)
    somewhere in the startup text on the gcode terminal. If not, you might have the incorrect branch. If you have the right branch. you may have set something up incorrectly, and you need to reset to factory defaults using M502.

    Hope it helps.

  • #890
    Quentin Harley
    Keymaster

    How is Morgan doing?

  • #893
    knarfishness
    Participant

    I’ll be verifying this afternoon that the branch that I’m on is correct, as well as resetting the board if I’ve got to. Even though the calibration looked close last time, my dry-run print was still trying to print itself on top of the top wooden frame, and not the bed.

    Once everything is working properly, I’ll need to more permanently secure my belts to the drivewheels, and then it’s print time!

  • #901
    Quentin Harley
    Keymaster

    Post your boot splash settings here before you start. You can always come back to it, or help me understand what is going on.

  • #1112
    knarfishness
    Participant

    < 6:00:37 PM: FIRMWARE_NAME:Marlin V1; Sprinter/grbl mashup for gen6 FIRMWARE_URL:https://www.morgan3dp.com PROTOCOL_VERSION:1.0 MACHINE_TYPE:Morgan EXTRUDER_COUNT:1

    That’s my splash message. Trying again today, M360 is once again working. Just had to hit the reset button on the PrintrBoard.

    I’ll let you know how calibration goes.

  • #1113
    Quentin Harley
    Keymaster

    For fastening your belts you could also look at the very nice belt clamps angrychisel made for his Morgan derivative

    I will be printing a couple, and should have something similar on Morgan git soon.

  • #1115
    angrychisel
    Participant

    Oh Quentin please don’t tell anyone about my over engineered belt clamps. I plan to make something simpler in the future, but I needed something quick to tighten the belts. I’m a tad bit embarrassed by them. I promise I will develop a simpler and easier to adjust system when I get a chance. I actually thought about incorporating the dovetail into the wheel in the future, that way you would only need to print 2 extra pieces. The belt wedge and the belt tightener.

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