Due to reasons… I’ve “adopted” a CR10s that a friend had bought. It was used, and was already well on it’s way to being a janky Printer of Theseus. My hope is to get it up and running and put through it’s paces before the holidays so I can give it back as a gift.

With the linear rail upgrades, I picked up the hardware and it’s on it’s way; which got me looking at how to do the upgrade, which I have mostly figured out; the question I’m having is, most upgrades seem to place the rails on 2020 extrusions sitting on top of the base frame- same as how the original y axis 2040’s were designed.

Which raises the question- why not lower it so the 2020 rails are even with the frame, with the mgn12 rail sitting on top? Like so:

The short answer I came to is this would necessitate replacing the brackets for the y stepper motor and it’s idler; but it should be possible. the easiest solution would be something like:

which raises the question: are printed parts rigid enough to hold against the tension on the belts? The motors can’t handle too much tension anyhow, and the printer already has the screw-cap tensioners for x and y printed that seem to have been holding up well.

has anybody replaced the OG metal bracket on the back? does it stress and need replacing often, or is it fairly reliable (and above all, consistent,)

  • @[email protected]
    link
    fedilink
    English
    58 months ago

    Printed parts can be rigid enough, prusa is using printed brackets. Just use ABS or simmilar

    • FuglyDuckOP
      link
      English
      38 months ago

      I expect you’re right, thanks for the sanity check.

      though, the prusa’s aren’t using printed brackets for the y axis motor mounts, as far as I can tell. I’m guessing that slugging around a print bed and whatever is being printed might cause it to Need replacement- but probably not “frequently”. Infrequently enough at least that I can help the kid through it. (So, the friend is maybe an idiot. not-engineering-minded)

      • @[email protected]
        link
        fedilink
        English
        48 months ago

        Check the mk3s printable parts , every motor on the mk3 is mounted using printed brackets, abs/Asa holds up really well and honestly petg does as well, I had a petg failure on my x axis after doing days of enclosed abs printing which says a lot considering it was easily 50+ deg c in the enclosure. I’ve since put probably a few thousand hours since rebuilding with abs and have had no issues with the printed parts.

        Vorons also use printed motor mounts and they also hold up with high enclosure temps for extended periods

      • @franzfurdinand
        link
        English
        38 months ago

        If you’re concerned about durability, you could potentially add in some bolts to use as a slip-in rigid spine to further reinforce the design. I’m thinking something similar to how concrete is tensioned to provide rigidity and strength.

        I’m spitballing ideas to see if I can spark something workable for you.

      • @[email protected]
        link
        fedilink
        English
        38 months ago

        RatRig V-minion uses printed (ASA/PETG) parts for all motors, and 10k mm/s² acceleration is normal. Granted, a smaller bed slinger, but still.

      • @Voyajer
        link
        English
        28 months ago

        Vorons use 3d printed mounts for all of their motors for another reference (5 perimeters and 40% infill iirc). I think it would be fine given you’re using asa/abs and maybe thicken the bracket model up a bit where the motor mounts if you want.

        • FuglyDuckOP
          link
          English
          48 months ago

          Thanks for the reassurance, lol. Taking a look at their mounts for… blatant plagiarism inspiration