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Discussion in '3D printers' started by Carl Feniak, Sep 29, 2014.

  1. nexty

    nexty New
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    Hi Carl,

    pretty neat print you've done!

    would that be ok if I print the .stl on PLA? infill 100%

    thanks guys looking forward to start building this one
     
  2. JCPhlux

    JCPhlux Well-Known
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    I think @Carl Feniak used 40% Honeycomb.
     
  3. nexty

    nexty New
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    I'm not in a rush, started to print the V-slot brackets

    will see how it goes, will surely post some pics!

    Quentin.
     
  4. Carl Feniak

    Carl Feniak Journeyman
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    Note: updated BOM
    Added extra 1/4" aluminum spacers to the BOM, they are needed for the two plate setup (two per wheel) and the mini V wheel kit only comes with one per wheel. Alternatively you could easily print this item. Just print them in multiples of 4 so they are identical in height.
     
  5. JCPhlux

    JCPhlux Well-Known
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    have you been able to find a low cost source for the spacers?
     
  6. Carl Feniak

    Carl Feniak Journeyman
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    If it wasn't for shipping the open build cost wouldn't be too bad. I have found that the shipping estimator is bad for small packages, but if you contact the staff they can get you a better rate.
    Here is a printable replacement.
    http://www.thingiverse.com/thing:502734
    Alternately, something like this plus a few M5 washers might do the trick, need to get to around 1/4" or 6.35mm.
    http://www.ebay.ca/itm/50x-5mm-Nylo...849?pt=LH_DefaultDomain_0&hash=item1e76411221
     
  7. JCPhlux

    JCPhlux Well-Known
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  8. DarkAlchemist

    DarkAlchemist Well-Known
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    WOW, I seem not to get updates to my email anymore when someone replies. :/

    I will say the I3 is a vibrating monster so 60-100mm/s for actually printing is as fast as I can go and I have it bolted down to a 3/4 inch plywood board. The non printing moves at 130mm/s is pushing it.
     
  9. DarkAlchemist

    DarkAlchemist Well-Known
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    This is what I see and there is nothing to click to get that excel file.
    [​IMG]
     
  10. Carl Feniak

    Carl Feniak Journeyman
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  11. Carl Feniak

    Carl Feniak Journeyman
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    Click on "files", the tab to the right of the "parts list" tab that you are on in the picture above. It is mixed in with the stl files. There are two copies; a xls and a xlsx. I tried putting it in the parts list area but couldn't get it to appear.
     
    #71 Carl Feniak, Oct 15, 2014
    Last edited: Oct 16, 2014
    JCPhlux likes this.
  12. DarkAlchemist

    DarkAlchemist Well-Known
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    Got it, thank you. :)
     
  13. JCPhlux

    JCPhlux Well-Known
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    ok @Carl Feniak
    I think this is my final design that I am going to print. I believe I have redesigned it with sloping overhands so the printer should handle it. Can you take a look and tell me what you think.
     

    Attached Files:

  14. Carl Feniak

    Carl Feniak Journeyman
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    I took a few pics of my extrusion for a visual. It may be an optical illusion, but I still think the extrusion inside corner fillet are too big a radius.
    IMG_0861.JPG IMG_0862.JPG
    Something I like to do to help my slicer (slic3r) print holes in a bridged section, is to put a 0.2mm layer at the bottom of the hole so that the first layer bridges right across the hole. You may want to consider doing this for the two holes shown below.
    Capture.JPG
    What is the width "w" in the pic above? If the idlers clear this then no concern, but if not I wanted to make sure there was enough room for a M3 washer between the to idler bearings, a width of about 8.5mm.
     
  15. JCPhlux

    JCPhlux Well-Known
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    I wonder is the design for the extrusion has changed. looking at the screen shot that I built from the v-rail spec sheet it should clear. But you are right it does look sharper in real life.

    0.2mm layer bridge is a great idea.

    below is the measurements.

    11.jpg 12.jpg
     
  16. nexty

    nexty New
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  17. nexty

    nexty New
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    I'm currently looking to order the V-slot rails (on the picture, looks I'm seeing double v-slot (20x40)?)

    http://openbuildspartstore.com/v-slot-20-x-20mm/

    BOM state 7 of 1meters, is that correct? I believe I might have to short some of those right?
     
  18. JCPhlux

    JCPhlux Well-Known
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    I have not looked at the v-slot requirements for @Carl Feniak build because I knew from the beginning I was not building the same size but I believe a 1000mm v-slot will need to be cut into 2 or 3 pieces ranging in length of 300mm to 500mm. Look at the second tab of the BOM it explains the cuts in greater detail.
     
    nexty likes this.
  19. nexty

    nexty New
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    ho thanks JC for that didn't seen that tab -

    so if a 8x8 bed, does the leadscrew still remain 300mm?
    Lead Screw Length:
    L
    300 mm

    thanks,
    Quentin.
     
  20. Carl Feniak

    Carl Feniak Journeyman
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    If memory servers me correctly: I printed mine in PLA with a 0.4mm nozzle, 0.2mm layers, 6-8 forced perimeters, 10-12 top/bottom layers, and 40% honeycomb infill.
    I've set the BOM to use all 20x40 extrusion. Certain pieces can be substituted with 20x20 if desired such as the lower 3 horizontals (not the Z motor rail) and the front top horizontal piece. You can see I used two pieces of 20x20 as I was short on 20x40 at the time.
    Exactly, the extrusion requirements will vary with build size. Open builds offers lengths in both 1m and 1.5m lengths, so you will have to do some more detailed math then what is done in the excel sheet to order the minimum required and reduce wastage.
    You can see from the picture of my printer that I gave a certain amount of room beyond the print bed. I am hoping it will allow dual extrusion in the future as well as a print cooling fan for printing PLA. Since I haven't made these accessories yet these lengths aren't optimized. I did the same with the Z lead screw length as there are different lengths of hotends out there. Feel free to increase or decease these amounts if you want more room or a tighter build.
     
    #80 Carl Feniak, Oct 16, 2014
    Last edited: Oct 16, 2014
  21. Carl Feniak

    Carl Feniak Journeyman
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    Completely up to you! I sourced 300mm lead screws so that is what I used and it is a fairly typical build height for reprap printers, excluding deltas. Open builds offers longer lengths of lead screws so feel free to modify this value in the sheet.
     
  22. Carl Feniak

    Carl Feniak Journeyman
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  23. Mark Carew

    Mark Carew OpenBuilds Team
    Staff Member Moderator Builder Resident Builder

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  24. nexty

    nexty New
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    wow, that brilliant!! how many hours?

    are you using slic3r? I'm still experimenting with the support material
     
  25. Carl Feniak

    Carl Feniak Journeyman
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    I don't have the exact hours as I turned of the power before checking. I'd have to say about 20hours. It ran overnight and ended some time while I was at work. I left it at default speeds 30/60/130.
    I am using the latest release of slic3r. I've found that pillar support works well and breaks away fairly easy.
     
  26. DarkAlchemist

    DarkAlchemist Well-Known
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  27. Giuliano M

    Giuliano M Well-Known
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    I'm considering building one of these C-Bots, but I wanted to use one of these (heavy) basalt bed substrates in a 300x300mm size:

    http://store.quintessentialuniversalbuildingdevice.com/product.php?id_product=51

    However, since the plate is very heavy (8 pounds), what do you think of supporting the Z gantry at four points, like this (image attached) ?


    I am thinking you could put the two Z rods in the middle of the two left-to-right bars, the ones with the bearing supports. They'd still be out of the way of the XY gantry.

    Or do you think there could be binding?
     

    Attached Files:

  28. Giuliano M

    Giuliano M Well-Known
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    Something along these lines is what I was thinking.

    Of course, with the rods being in the center of the front and back, accessing the build plate from the "front" where the motors are mounted could be awkward... but then you have plenty of access from the sides.

    The plate in the middle is 300 x 300 mm, and most of the 20x40 pieces are 500mm long, except for where they had to be cut shorter.

    The 8mm lead screw rods are about 425mm long, easy to cut a 1000mm rod in half.

    C-Bot - Sketchup Build.jpg
     
    NeoGames76 likes this.
  29. Carl Feniak

    Carl Feniak Journeyman
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    I've seen others that have used a similar setup with smooth rod and linear bearings. It seems that they don't have any issues, but my concern is that there is a risk of slight teetering left and right. The actual forces involved would be quite small if everything is balanced, but an unbalance can also create a constant predictable force direction. You might get away with only eight V-wheels, either all inside or outside the extrusion.
    Only speculation.
    The alternative would he a heavy duty redesign of the current Z arrangement to full size solid V wheels, dual plate setup, and 20x60 or even 20X80 extrusion.
     
  30. DarkAlchemist

    DarkAlchemist Well-Known
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    Speaking about teetering I have done a lot of printing with my Prusa I3 Rework and I swear I can see teetering when Z moves like the two motors are not completely in sync. I print just fine but I still say two motors running off of one connector (essentially) is not a good idea. How is it that CNC routers, and mills, use only one Z motor and they work just fine while we went to two motors being ran off of, essentially, a Y connector?
     

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