MakerBot Build Status

The body is painted, bolted together, rods have been cleaned, XY stage installed, boards soldered and bolted on, cables run.1  I’ve affixed the opto-endstop triggers on the X and Y axes.

  • I have not installed the Z axis endstops mostly because I’m just not that keen on marring that beautiful clear acrylic sheet that is the Z stage.  I’ve created a little fitting out of balsa wood that will eventually support the opto-endstop triggers.
  • I’ve assembled the two “dinos” but not any other parts of the plastruder.
  • I need to assemble the rest of the plastruder, drop it in, and fire it up!
  1. Even if the opto-endstops are going to the wrong max/min ports for the moment. []

One step forward, two steps back

As I mentioned, I had installed the Z-axis threaded rods without actually cleaning them first.  It wasn’t that bad to undo the caps, pull them out, and clean them.  In fact, it was kinda fun.

The process involves covering one end of the threaded rod with electrical tape to protect the threads and your drill, inserting that end into an electrical drill, adding 3-in-1 oil to the rod, and running the drill while holding a paper towel to the threads with a thumbnail.  It worked great and went much easier than I thought it would be.  I also used this opportunity to lower the threaded rods into the lower section of the MakerBot.  I’ll need to make sure they don’t get caught on any wires, but that will be all part of the process of zip tying all of the wires down anyhow.

Since I was going over things I had already done, I went ahead and also tightened up the Y-axis pulley.  It’s kind of a pain to adjust once the XY stage is installed, but I happen to have a very small adjustable wrench that was able to reach underneath the XY stage.

Christmas robot shopping

I went to the hardware store after work today to pick up the items on my shopping list.  Walking to their register I fell victim to their bargain basement aisle.  In the process I dropped the $3 superglue I had found and picked up four times as much for $2.  Sure, its a no-name house brand…  but as long as its reasonably sticky there shouldn’t be any problems.

I also picked up some 3-in-1 oil for the various rods.  I installed the Z-axis rods without cleaning them properly (too enthusiastic to get building).  I also bought a large flexible magnet in sheet form (the kind used for fridge magnets – only in an 8.5″ x 11″ size), work gloves, and another utility knife.

Adding the circuit boards

Once I had the opto-endstops all soldered up, I really wanted to keep going.  I made the Y-endstop cables, bolted the opto-endstops on, and bolted the motherboard and stepper motor boards to the MakerBot.  Clipped in the cables and it looks like a robot after all!  I’m going to need to organize those cables, but that will have to wait until all the other parts are in place.

An interesting side note – as I was moving the various axes someone noticed that little lights started flashing on the stepper motor boards!  Cool!  I presume moving the platform caused the motors to act like generators and pushing power to the boards, lighting up the LED’s.

Once the opto-endstops were done, I couldn’t resist bolting them on.  Once I started doing that, I wanted to make the Y-endstop cables, then the ribbon cables, and wire it all up.

If nothing else, it looks like a robot now!

Things I learned while soldering opto-endstops

The opto-endstops marked the very first parts I had to solder for this MakerBot.  Not having soldering anything more complicated than two wires together, this was an adventure and learning experience.  Here’s what I learned today:

  • The 3-pin connectors used for two of the opto-endstops (on the Y-axis stage) are in the Generation 3 MakerBot Electronics Kit (Mostly Assembled) with some of the other connector bits.  I was a little confused about this for a while.
  • It helps to lay out all the little bits in an organized fashion beforehand.
  • Keep a long thin rigid stick handy for bending delicate leads into the circuit board holes.
  • Although I read the RepRap electronics fabrication guide and found it helpful, I still felt a little lost.  I found the most effective way to solder the parts in was to:
    • Get the soldering iron good and hot
    • Put the leads through the holes
    • Bend the leads a little so that they stayed in place
    • Flipped the board over so the leads were sticking up
    • Touched the solder to where I wanted the joint
    • Gently stroked the solder with the soldering iron tip towards the joint
    • This process seemed to create a pretty good joint
  • You’re going to burn a finger at some point, accept it.1
  • This almost goes without saying, but go slowly.
  • Check and double check the orientation and placements.
  • I found it helpful to take a large sheet of aluminum foil and shape it into a tray.  This helped contain the parts I was working on and was a good way to catch the flying leads that I clipped off.
  1. I burned two. []

Opto-Endstops arrived today!

Huzzah!  I have been both excited and a little bit apprehensive about these parts.  I have to admit I was almost relieved that they were accidentally swapped out – forcing me to skip their assembly for a little while.  Now that they’ve arrived I need to actually solder these itty bitty parts.

I have a soldering kit I use about once or twice a year – and never for anything more interesting than connecting two wires.  For some reason I find soldering little bits more intimidating.  With my trusty soldering iron and a steady hand, on to adventure! 1

  1. “Oh, sister Magdelene won’t you fetch the
    Doctor’s flask.
    He is going to need a steady…
    A steady hand”
    Cracker – Take me down to the infirmary []