Return to the BUILD

“The main part provided is the drive motor that power R2-D2’s right wheel, which comes complete with its own gearbox and circuit board. With this in place, you will be able to wire up and assemble most of R2-D2’s right leg.”

This may be our biggest issue yet. It has so many steps in it that they chose to skip the entire Understanding Robotics section of the magazine.



Materials: The Cable Ties are plastic and the motor/gearbox is mostly metal.


  • Building The Galaxy – Industrial Light & Magic
  • Droid Directory – B1-Series Battle Droids Part 1
  • Build R2-D2: Model Instructions


Fitting the Motor and Wiring

Step 1

Fit the square drive spindle of the Right Wheel Motor/Gearbox into the center of the wheel axle from Issue 28:

Step 2

Align the motor casing with the four matching holes in the Outer Wheel Mounting Plate:

Steps 3-4

Secure the motor into place with four (4) 2.5×10 mm silver screws we received back in Issue 28:

Step 5

Retrieve the Motor Cable from Issue 17. Connect the larger plug of the Motor Cable to the socket on the motor’s circuit board:

Step 6

Thread the other end of the Motor Cable up between the leg and the Right Ankle Plate:

Steps 7-8

Feed the larger plug of the Infrared Cable from Issue 17 up the leg in the same way:

Step 9

Slide a Cable Tie through this retaining loop on the metal leg frame, making sure it is orientated correctly for Step 11:

Step 10

Before securing the cables in place, make sure the end of the smaller plug of the Infrared Cable is 5-5/16″ (135mm) from the retaining loop:

Step 11

Loop the Cable Tie around the cables and pull it tight.

Make sure you leave a little slack in the Motor Cable here between the Cable Tie and the motor itself:

Steps 12-13

Repeat this Cable Tie process at the remaining three retaining loops in the metal leg frame:

Step 14

Cut off the excess ends of all four Cable Ties.

I recommend using sprue cutters or a sharp hobby knife here for nice clean cuts. Take care not to damage the wiring:

Fitting the Leg Casings

Step 1

Retrieve the Right Sensor from Issue 20 and uncoil the cable. It is going to fit in to this big hole in the leg assembly from Issue 19:

Step 2

Plug the Right Sensor into the round hole at the shoulder. It should sit flush.

The front edges of this sensor are soft, so I recommend putting the front through the hole first, then sliding the back down into the slot:

Step 3

Feed the Right Sensor lead out through the large hole in the center of the shoulder:

Step 4

Feed the ends of both the Motor Cable and Infrared Cable from the previous section through the same hole:

Steps 5-6

Make sure the Right Ankle Mounting Plate is far enough down the leg, then align the inner and outer leg casings, paying attention to the protruding lugs and matching holes:

Step 7

Slide the Right Ankle Mounting Plate up over both casings to lock them together:

Step 8

Fit the Right Leg Outer Plate assembly completed back in Issue 2 onto the outer shoulder:

Step 9

Secure the leg casings together with twelve (12) 2.3×6 mm black screws:

Steps 10-11

Turn the leg over. Then, take the Right Ankle Fitting assembly from Issue 8 and, noting the four protruding lugs and matching holes, press it neatly into place:

Step 12

Turn the leg assembly over again, and drive one (1) 2.3×6 mm black screw into this hole to lock the fitting into place:

Step 13

Take the Right Leg Bottom Rear Cover from Issue 21 and plug the Right Lower Leg Details from Issue 14 into the holes on each side:

Step 14

This Right Leg Bottom Rear Cover assembly has a recess (circled below) which provides clearance for the cables in the next step:

Step 15

Fit this assembly over the inside of R2-D2’s ankle, making sure the leg cables are within the recess mentioned in the last step:

Step 16

Secure the Right Leg Bottom Rear Cover assembly into place with four (4) 2.3×6 mm black screws.

The instructions are wrong here, they say to use silver screws, but they meant black:


The right leg is complete! We still have to add the foot coverings, but the leg itself is a beauty. There was so much to do in this issue. I wish all of them were like this, so here is to hoping for more ‘full’ issues like this one!

Next Up

 Issue 31 – Outer/Inner Foot Casings

Leave a Reply

Your email address will not be published. Required fields are marked *