Return to the BUILD
“This [issue] brings you the parts to complete [Issue] 100, which includes fitting R2-D2’s head and his rear body panel. The last step is to install his batteries, which need to be prepared as explained in [Issue] 92. Once that has been done, you are ready to load the app onto your smartphone or tablet, activate R2-D2 and set him going!“
Materials: The Cable Tidy and Plastic Studs are vinyl, while the rest of these parts are electrical.
- Build R2-D2: Model Instructions
- Build R2-D2: Mains Adaptor and Wiring
- Build R2-D2: Controlling R2-D2
Connect the Extension Speaker Cable to this matching Speaker socket on the MCU:
Route the other end of the Extension Speaker Cable over the Sensor Control Board and out under rear of the Middle Ring Section BF-13:
Fit the two Cable Labels marked C-IN (Control In) to each end of the PCB Cable (the one with the two rows of 5 wires):
Fit the two Cable Labels marked H-OUT (Head Out) to each end of the Distribution Board Cable (the one with the two rows of 6 wires):
Bring the red plug on the PCB Cable and the white plug of the Distribution Board Cable together, then wrap the entire length of both cables with the Cable Tidy.
I decided to wait on wrapping these cables inside the Cable Tidy until later on, but this is how the two cables should be arranged:
Connect the red plug of the H-OUT cable to this red socket on the Distribution Board inside the Dome assembly:
Connect the white plug of the C-IN cable to this matching white socket on the Dome Circuit Board. Try not to touch the circuit board itself:
Here is where I wrapped both cables inside the Cable Tidy. The reason I waited until now was so I could see where the cables came together at the Dome Support Arm and start wrapping them together there:
Secure the cable bundle to the Dome Support Arm with a Cable Tie as shown and cut off any excess Cable Tie.
You will want these wires to route towards the center of the Dome:
Fitting the Head and Back
Retrieve the shorter Dome Spindle (from Issue 95) and slide it into down through the bearings in the Dome Support assembly until it seats into the Bearing at the very top of R2-D2’s head:
Bring your Dome assembly close to the top of R2-D2’s body and begin feeding the bundled dome wiring down through D-shaped Cable Retainer and then into the square hole on the right of the Dome Motor Support Plate.
It is very helpful here to get someone to support the dome while you are routing the wiring bundle down into the body:
While holding the Dome Spindle up inside the Dome, slowly lower the head down onto the body, feeding the spindle into the Dome Drive Shaft. The Dome will sit flush when the four tabs of the Dome Support Centre fit into the slots at the top of the Dome Drive Shaft. You may have to rotate the Dome a little to get this to line up correctly:
At this point, you should also be able to turn R2-D2’s head by hand almost 180° in both directions, until the protruding tab of the Dome Support Arm stops by contacting the buffers we installed back in Issue 98.
While I could turn my Dome fully in both directions, I ran into a problem: This bottom wiring of the Lightsaber Ejector was hitting a few things inside R2-D2, most notably the Dome Motor Support Plate:
I had heard of other builders encountering issues with these wires breaking off and I am guessing this is why. To fix it, I decided to gently bend the leads of the switch to the side and zip tie them up in place, like this:
Success! This modification keeps the wires from hitting anything inside R2-D2 as we move the head around:
But now, the slack in the wiring above the switch started catching on things, so I used a piece of electrical tape to secure it to the ejector frame. This solution worked perfectly for me:
Making sure the bundled wires from the dome are not tangled, then connect the white plug of the H-OUT cable to this matching socket on the right-hand side of the MCU:
In the same way, connect the red plug of the C-IN cable to this matching socket on the MCU:
Secure the wire bundle to the Dome Motor Support Plate with a Cable Tie as shown, and cut off any excess Cable Tie.
In order for our Dome to be able to rotate fully in both directions without pulling on the bundled cables, some of the Dome wiring bundle (inside the Cable Tidy) has to be above the D-shaped Cable Retainer. However, when I moved enough of the bundle above the retainer to allow unhindered rotation, the lower section of the wiring bundle would bulge out and hit the Lightsaber Ejector. I tried to secure the bundle per the instructions for this step, but that was not effective enough. Instead, I used a long zip tie to secure the Dome wiring bundle to the Bearing Housing around the Dome Shaft (I did not secure it to the Dome Shaft itself). This solved my problem and I now have unrestricted rotation of my Dome in both directions:
Bring your Rear Panel assembly to the back of R2-D2 and connect the Extension Speaker Cable to the Speaker plug:
While tucking the Speaker wiring inside the lower metal frame, carefully slide the Back Panel into place onto the frame until it is flush with the Front Panel assembly and the mounting holes are aligned.
As I mentioned back when we fitted the Front Panel in Issue 98, don’t forget about the long tabs along the bottom edges of the Back Panel that need to slide into the lower slots of the frame:
The main assembly of your R2-D2 is now complete. There should be no significant gap between the front and back panels, and the gap between the dome and body should be 2.5 mm or less all the way around.
Make sure the Front Panel and Rear Panel assemblies are aligned with the top holes in the underlying frame. Then, secure both panels into place with four (4) 2.5×6 mm silver screw, two on each side:
In the same way, secure the bottoms of the front and rear panels with four (4) more 2.5×6 mm silver screws, two on each side:
Three sets of Plastic Studs are in this issue designated A, B, and C. Cut these Plastic Studs from the sprues, but keep them separated.
The four short (A) Plastic Plugs are used to cover the screws at the top of the front and back panels. Match the angle of the plug to the panel and press these into place as shown.
CAUTION: I *highly* recommend installing these Plastic Plugs AFTER you complete the Powering Up section below and are satisfied with R2-D2’s operation. If you have any problems, like I did, removing these plugs to get inside R2-D2 may damage the Body or the Plugs.
The four long (B) Plastic Plugs are used to cover the screws at the bottom of the front and back panels. Match the angle of the plug to the panel and press these into place as shown:
The four angled (C) Plastic Plugs are used to cover the screws at the top inner corners of the power packs on the two outer legs. Match the angle of the plug to the panel and press these into place as shown:
Open the Right Tool Compartment Door and apply the Sticker for Switch Board to the inside, as shown:
Open the flap in the dome covering the Lightsaber Tube.
If you are having trouble opening this flap, use a small piece of tape to pull it up:
Gently lower the Lightsaber assembly (from Issue 41) down into the Lightsaber Tube, and then close the flap:
That’s it! Construction of your R2-D2 is fully complete. Now, it is time to see if everything works…
“You are now ready to install the batteries and power up R2-D2. Refer to Issue 92 for information on testing and preparing the batteries, which must be done before installation. These steps guide you through the whole process, but you should also read Controlling R2-D2 carefully to see what happens when he powers up.”
IMPORTANT: Make sure that R2-D2’s Main Switch is turned OFF (the ‘O’ symbol should be depressed).
I moved this to the first step as it is very important that R2-D2 is turned off completely before installing the batteries:
We have done this first items a few times, so I will summarize them:
- Using the Small Screwdriver, loosen the captive screws in the rear Access Panel and pull the panel out and down
- Slide the Battery Box out and remove the two screws holding the cover on
- Remove the Battery Box Cover by sliding it off
Insert your six prepared 18650 Li-Ion batteries into the Battery Box, noting the ‘button-top’ positive terminal goes at the end of the slot without the spring (verify using the diagrams inside each battery slot):
Again, since we know this process, I will summarize a few steps here:
- Refit the Battery Box Cover and replace the screws
- Slide the Battery Box back into its mount inside R2-D2, taking care to slide the cables safely inside
- Screw the Access Panel back into place.
Plug the barrel plug end of the Mains Adaptor into the Charging Socket on the bottom of R2-D2. Plug the other end into a powered wall socket and wait a few seconds. Then, unplug the Mains Adaptor at both ends.
This is a protection procedure to activate the batteries, and without doing this R2-D2 won’t turn on. Going forward, this procedure is not needed and the Mains Adaptor will only used for charging the batteries inside the Battery Box.
Turn the Main Switch to the ON position (the ‘I’ symbol should be depressed).
After reading the Controlling R2-D2 page to become familiar with his operation, press the bottom Control Button (Power On/Off) on his front panel to turn him on.
CAUTION: R2-D2 will jerk forward slightly when turned on, so make sure he is in a safe place to do so:
R2-D2’s normal start-up process is to move forward to calibrate his foot motors, rotate his head in both directions, make a sound, and illuminate status displays to indicate he is ready for action.
Unfortunately, my R2-D2 did not function as expected. When I turned him on, he jerked forward correctly, but then his dome turned to the right, touched the bump stop, and kept trying to rotate. I could hear the Head Motor inside still running, so I immediately shut him off with the Main Power Switch to prevent any damage to the motor.
After some careful thought, I thought I may have had an problem with the Right Rotary Sensor that tells the MCU that the head is rotated fully to the right and to stop driving the Head Motor. This picture here shows which part I am referring to:
I ended up taking the Back Panel off to see what was wrong. This is the reason why I recommend waiting to install the Plastic Studs just in case we need to get back inside R2-D2. Thankfully, I quickly found that I had pulled the plug out of the sensor when I used the Cable Ties to secure the Rotary Sensor wires to the metal shaft. You can even see the loose plug in this picture from earlier in the build. I plugged the cable all the way back, reassembled R2-D2, and turned him on again. This time, he fired up and completed his start-up sequence without any further issues:
I set up R2-D2 on my local Wi-Fi and drove him around a bit, turned on his LCDs, made him talk, and tested a few more things, like the arms here…
… and the Lightsaber ejection mechanism here. Everything worked perfectly!
NOTE: I have created a separate Controlling R2-D2 page covering the full operation of your R2-D2.
With R2-D2 fully powered up, I took a few pictures of him from different angles:
He is alive! After 100 magazines and a few little hiccups here and there, we have completed the DeAgostini 1:2 scale Star Wars R2-D2 partwork build! We had a few problems along the way, but all in all it was a great experience. I do wish he was a little bigger; the real R2-D2 droid has a dome diameter of 18.25″ while this guy’s dome is 8″ across. That means this model is actually less than half-scale and more like 1:2.3 scale. Still, the details are there and he is great fun!
Controlling R2-D2 – Using R2-D2 manually or via the mobile application