Posts Tagged ‘ assembly

Building the C-Bot 3D printer: Part 9 : Assembly Day 2

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After re-printing the two ‘rear XY idlers’, the extrusions fit perfectly, so I was ready to reassemble the top of the frame.  Overall it went pretty seamlessly:  again, I just had to mentally track how many extra t-nuts to pre-load into all the extrusions.  I’ve added enough to add an extra extruder / spool holder on either side of the frame in the future.

Squaring the frame took a long time:  I’ve never ‘squared’ anything, and although I have a nice metal carpenters square, it seemed laborious and repetitious.  I ended with this process: measure the horizontal distance for all X distances:  Find the longest, and adjust the rest to match.  Repeat that on Y.  Stick the square on the corner, curse at it.  I hope that things will roll smoothly later…

Today my Rumba & LCD screen showed up too, so other than the pulleys that’ll go on my XY steppers, all parts are arrived.

Gotchas:

  • I somehow managed to only order 8 ‘Black Angle Corner Connectors‘, when the bom clearly states 18.  So, I ended up printing a bunch out to compensate until the metal ones show up.  Not sure how I missed that :S
  • The two ‘rear XY idlers’ accept captive nuts for the pulley system you build.  However, I was unable to actually get the nuts shoved far enough back in their cavity to actually line up with the bolt:  In fact, at one point I thought I may have to reprint a piece since the nut was jammed in, blocking the bolt.  But much tapping and picking with my dental-tool removed it.  End result:  No captive nuts inserted.  But the bolts are threaded through so much plastic, I don’t see this as an issue (yet?).

Time today:  About three hours.

day2

Assembly day 2 progress


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Building the C-Bot 3D printer: Part 8 : Assembly Day 1

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Finally began bolting stuff together.  Today I completed:

  • The lower XY frame, and long Y-legs, plus dual lead-screw steppers.
  • The Bowden extruder assembly.  I previously printed Mason’s derivative of Carls design (which links to the install directions).
  • The Core-XY gantry interior (no wheels yet, since the upper frame is incomplete).
  • A few bits on the top frame : There was something wrong with both ‘rear XY idler’ prints:  The v-slot extrusions wouldn’t fit in them, but fit into everything else.  So they’re currently re-printing…

All this was done following the c-bot assembly guide, and staring at pics of Mason’s and Carl’s bots.  The trickiest bit is to figure out how many t-nuts to pre-load into each extrusion for the future attachments…

Gotchas:

  • When assembling the Bowden extruder, I didn’t have any M3 bolts the correct length to screw the pivoting arm into the stepper block:  I needed to cut a 25mm bolt down to 14mm:  Worked like a charm.
  • Double-Gotcha:  I later needed that bolt to mount the HBP.  So I had a 3-legged HPB for a while…

Here’s the current build status, with the Replicator re-printing the ‘rear XY idler’  in the background…

Time spent:  About two hours.

day1

Assembly, Day 1!


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