Prusa i3: Graber edition: Mounting the Axes

Once the frame is complete, it's time to mount the axes - X, Y and Z.  To do this I printed various bits to make life easier, or to make the printer more robust.

Z Motor Install
First install the two Z motors - one on each side.  I twisted the cables first, to cut down on stray noise, then sheathed them so they'd look nicer.  There are slots in the base to run the motor wires, too.

For this step, you need:

• 2 Nema 17 motors
• 8 8-10mm M3 socket cap screws
• 8 M3 washers.

 
The next step is the X Idler, which will also construct the Z axis.

 You need:

• Wood: P, R, Q, Q, V, F, U, U.
• 4 1.5" 6-32 screws
• 4 6-32 nuts
• 1 M5 nut
• 2 LM8UU
• 2 3/4" 6-32 screws
• 6-32 washers
• 2 more 6-32 nuts
• 1 30mm M8 bolt (note: the one I used was too long)
• 1 608ZZ bearing
• 1 M8 nut (2 if your bolt is too long)
• 8mm Z Smooth Rod
• M5 Threaded Rod

The assembly is a bit confusing.  You have three horizontal plates, with three end caps and two internal spacers - best to check out the video.  Luckily, there's really only one way it'll work, and the X Motor mount uses the same configuration.

The long screws hold the assembly together; the short screws are used to clamp the M5 nut in between the two top plates.  That nut is your Z motion.  The M8 bolt holds the idler in place, making for a nice compact assembly.

 Here the M8 bolt I'm using is too long - if you use a 30mm bolt, you can go straight in - keeping the nut in between the first two plates, and then the idler resting on the end of the bolt.  I replaced this later.

The next step is the X Motor Mount.  The assembly is configured almost identically to the idler, except that there's a motor slapped onto the end.

Parts Needed:

• Wood: Y, X, Q, Q, W, AA, Z, Z.
• 4 1.5" 6-32 screws
• 4 6-32 nuts
• 1 M5 nut
• 2 LM8UU
• 2 3/4" 6-32 screws
• 6-32 washers
• 2 more 6-32 nuts
• 4 8-10mm M3 screws
• 4 M3 washers
• 8mm Z Smooth Rod
• M5 Threaded Rod
• 2 * 8mm X Smooth Rod
• 3 more LM8UUs - put 'em on the X rods before mounting them :-)  I forgot this step, had to dismantle a bit to get 'em in afterwards.

Y Assembly
Next up is the Y assembly.  For this, I printed two parts - an LM8UU holder, and a double nut trap - to make my life easier, and make the machine more reliable.

Parts Needed:

• Wood: O, O, O, O
• 6 10mm M3 screws
• 6 M3 nuts
• 3 LM8UU bearings
• 3 nut traps (http://www.thingiverse.com/thing:325681)
• 3 LM8UU clamps (http://www.thingiverse.com/thing:325681)
• 8mm Y Smooth Rod
• 4 1/2" 6-32 screws
• 4 6-32 washers
• 4 6-32 nuts
• 4 zip ties