Airplane

My wife and I regularly watch a television show from the BBC called "The Repair Shop". The show features a group of extremely talented ceramics, woodworking, metalworking, horologist, electronics, stitching and sewing staff that specialize in restoring antiques and family heirlooms.

One of the shows featured an antique toy airplane mechanism that really intrigued us, so I decided to attempt my own 3D printed version and "Airplane" is the result. The model consists of two major components, the airplane and the track. The airplane is designed to follow the track until it reaches a lifting mechanism, which lifts the airplane into "flight" then sets it back down to continue its travels around the track.

The original antique version utilized windup gear boxes for energy, my version uses a 3.7vdc lithium polymer battery to power the plane, and a five volt dc power supply to power the lifting mechanism and charge the plane's battery. The design is basically electromechanical, using various electrical components I have acquired over the years.

There are a few options for 3D printing and assembling the model. First, for a simple table top airplane, you can simply shorten the track guides on the airplane chassis to allow for table top clearance using a small hand saw or wire cutters. Second, you can 3D print four curved track sections for a round track, or 3D print four curved track and two straight track sections for an oval track for the airplane to traverse. And finally, you can print two lifting mechanism assemblies and have the airplane take off twice during its travels around the track.

We truly enjoy watching "The Repair Shop", and hope you enjoy this model!

As usual I probably forgot a file or two or who knows what else, so if you have any questions, please do not hesitate to ask as I do make plenty of mistakes.

Designed using Autodesk Fusion 360, sliced using Ultimaker Cura 4.12.1, and 3D printed in PLA on Ultimaker S5s.

1. Soldering iron and solder.
2. AWG 28 Wire.
3. Thick cyanoacrylate glue.
4. Thick double sided tape.
5. Thin double sided tape.

I acquired the following parts:

1. One N20 500rpm 6vdc gear motor.
2. One N20 15rpm 6vdc gear motor.
3. One USB battery charger: https://www.amazon.com/gp/aw/d/B0BRXYZTWN?psc=1&ref=ppx_pop_mob_b_asin_title
4. One micro slide switch: https://www.amazon.com/gp/aw/d/B007QAJUUS?psc=1&ref=ppx_pop_mob_b_asin_title
5. One pogo two pin magnetic connector: https://www.amazon.com/gp/aw/d/B0D45666MG?psc=1&ref=ppx_pop_mob_b_asin_image
6. One 3.7vdc 160ma lipo battery: https://www.amazon.com/gp/aw/d/B09WN9W5YV?psc=1&ref=ppx_pop_mob_b_asin_title
7. Two micro roller switches: https://www.amazon.com/gp/aw/d/B0CPM173BB?psc=1&ref=ppx_pop_mob_b_asin_image
8. One optical sensor: https://www.amazon.com/gp/aw/d/B0CHDRF497?psc=1&ref=ppx_pop_mob_b_asin_title
9. One 5VDC reed relay: https://www.amazon.com/gp/aw/d/B0D2MSR8H6?psc=1&ref=ppx_pop_mob_b_asin_image
10. One 5vdc dpdt relay: https://www.amazon.com/gp/aw/d/B09P1DC5YK?psc=1&ref=ppx_pop_mob_b_asin_title
11. Two O-Rings (R16: 18MM ID, 3.5MM section).
12. Four 3mm diameter by 2mm thick neodymium magnets.
13. Two M2 by 20mm cap screws with nuts.
14. Two m2 by 8mm cap screws with nuts.
15. Two 11mm diameter nylon spheres.
16. Two 1n2007 diodes.
17. One 5VDC power supply.

I 3D printed the following parts at .15mm layer height, 20% infill:

1. One "Cam Reverse.stl"
2. One "Cam Run.stl"
3. One "Charging Base.stl"
4. One "Chassis.stl"
5. One "Fuselage Body.stl"
6. One "Fuselage Nose.stl"
7. One "Gear (1m, 11t).stl"
8. One "Gear Lift Rods Mount (1m, 24t).stl"
9. One "Gear Worm.stl"
10. One "Gear, Motor (1m 8t).stl"
11. One "Horizontal Stabilizer.stl"
12. One "Lift Rod Base.stl"
13. Two "Lift Rod.stl"
14. One "Lift Rods Mount Bushing Long.stl"
15. One "Lift Rods Mount Bushing Short.stl"
16. One "Lift Rods Mount.stl"
17. One "Pogo Magnetic Pin Connector Mount.stl"
18. One "Propeller.stl"
19. Four "Track Segment Curved Dovetail.stl"
20. One "Track Segment Straight Dovetail.stl"
21. One "Track Segment Takeoff Dovetail.stl"
22. One "Wheel Axle.stl"
23. Two "Wheel.stl"
24. Two "Wing Bolt.stl"
25. One "Wing Left.stl"
26. One "Wing Right.stl"
27. One "Wing Spar.stl"

This mechanism is a high precision print and assembly using at times very small precision parts in confined spaces with highly precise alignment. Prior to assembly, I test fitted and trimmed, filed, drilled, sanded, etc. all parts as necessary for smooth movement of moving surfaces, and tight fit for non moving surfaces. Depending on your slicer, printer, printer settings and the colors you chose, more or less trimming, filing, drilling and/or sanding may be required to successfully recreate this model. I carefully filed all edges that contacted the build plate to make absolutely certain that all build plate "ooze" is removed and that all edges are smooth using small jewelers files and plenty of patience.

This mechanism also uses threaded assembly, so I used a tap and die set (M6 by 1) as required for thread cleaning.

To assemble the airplane, I performed the following steps:

1. Pressed the N20 500rpm 6vdc gear motor into "Chassis.stl".
2. Glued the micro slide switch and one half of the pogo magnetic connector into "Pogo Magnetic Pin Connector Mount.stl".
3. Pressed the magnetic connector assembly onto the chassis rear track guide then glued it in place.
4. After attaching the battery to the chassis using thin double sided tape, and the USB charger to the side of the motor using thick double sided tape, I wired the assembly as shown in the airplane wiring diagram.
5. Pressed "Gear Worm.stl" through the hole in the front of the chassis assembly then onto the motor shaft.
6. Positioned "Gear (1m, 11t).stl" between the landing gear struts, slid "Wheel Axle.stl" through one strut, through the gear, then through the remaining strut. then glued the gear onto the center of the axle.
7. Place one O-Ring on each "Wheel.stl".
8. Pressed one wheel onto each end of the axle assembly.
9. Pressed the four magnets, two into "Fuselage Body.stl" and two into "Fuselage Nose.stl" with matching polarities such that the nose magnetically attached to the fuselage.
10. Slide the fuselage nose onto the chassis assembly.
11. Pressed "Propeller.stl" into the worm gear.
12. Slid the fuselage onto the chassis.
13. Pressed "Horizontal Stabilizer.stl" into the slot in the rear of the fuselage, through the slot in the rear of the chassis, then out the remaining fuselage slot making certain the horizontal stabilizer was centered on the fuselage.
14. Pressed "Wing Spar.stl" through the slot near the front of the fuselage, through the slots in the front of the chassis, then out the remaining front fuselage slot making certain the wing spar was centered on the fuselage.
15. Attached "Wing Right.stl" to the right end of the wing spar using one "Wing Bolt.stl"
16. Repeated the previous step with "Wing Left.stl".

To a assemble the optical sensor assembly, I performed the following steps:

1. Desoldered and removed the three pin connector from the optical sensor.
2. Using a sharp modeling knife, carefully removed the black shield from the optical sensor.
3. Cut the inner leads of both the optical sensor emitter and detector.
4. Bent both the emitter and detector horizontally.
5. Soldered a small wire between the emitter and the circuit board emitter pad, and a second small wire between the detector and the circuit board detector pad.
6. Pressed the black shield onto the optical emitter and optical detector.
7. Soldered the reed relay "+" pin (pin 2) to the optical sensor board "Vcc" pin.
8. Soldered the reed relay "-" pin (pin 3) to the optical sensor "Out" pin.

To assemble the takeoff track segment, I performed the following steps:

1. Pressed "Lift Rods Mount Bushing Long.stl" onto "Lift Rods Mount.stl"
2. Slid the assembly into "Lift Rod Base.stl" into the position as shown.
3. Positioned "Gear Lift Rods Mount (1m, 24t) in the base assembly as shown, then slid the lift rods mount through the gear.
4. Positioned "Cam Run.stl" into the position as shown, then slid the lift rods mount through the cam.
5. Positioned "Cam Reverse.stl" into the position as shown, then slid the lift rods mount through the cam.
6. Slid "Lift Rods Mount Bushing Short.stl" onto the lift rods mount.
7. Attached the two micro roller switches to the base assembly using two M2 by 20mm cap screws and nuts.
8. Pressed "Gear, Motor (1m, 8t).stl" onto the 15rpm gear motor shaft.
9. Pressed the gear motor and gear into the base assembly making certain the motor gear meshes with the lift rods gear.
10. Attached the 5VDC dpdt relay to the base assembly using thin double sided tape.
11. Secured the optical sensor assembly to the bottom of "Track Segment Takeoff Dovetail.stl" using two M2 by 8mm cap screws and nuts
12. Pressed the base assembly into "Track Segment Takeoff Dovetail.stl".
13. Wired the assembly as shown in the lift mechanism wiring diagram.
14. Glued one 11mm nylon sphere to the non-threaded end of "Lift Rod.stl", and repeated this process with the remaining 11mm nylon sphere and lift rod.
15. Threaded the two lift rods into the lift rods mount.

To assemble the charging base, I performed the following steps:

1. Soldered red and black wires to the pogo magnetic connector matching the polarity of the pogo magnetic connector in the airplane.
2. Slipped the wires down through the top of "Charging Base.stl" and out the side opening.
3. Glued the pogo magnetic connector into the top of the charging base.

For final assembly, I performed the following steps:

1. Pressed two "Track Segment Curved Dovetail" together.
2. Pressed the remaining two curved track segments together.
3. Joined the two curved track segments together using "Track Segment Straight Dovetail.stl" and the takeoff track assembly, or two takeoff track assemblies.

With assembly complete, I applied power to both the track and airplane, positioned the airplane in front of the lifting mechanism, then watched the lifting mechanism lift and lower the airplane making slight adjustments to the position of the lifting base across the takeoff track to ensure the plane was lifted from and lowered onto the track, and adjusted the optical sensor position for proper distance from the lift rods. When satisfied with the alignment, I glued the lifting base to the takeoff track segment and tightened the optical sensor screws.

To charge the airplane, apply power to the charging base, slip the rear track guide into the charging base rear track guide hole then slide the airplane down until the pogo magnetic connectors attach. The red LED on the usb charger will illuminate red while charging, then green when charging is complete.

And that is how I 3D printed and assembled "Airplane".

I hope you enjoyed it!