This is an original design created for the Flying Objects design contest and features a handheld three-stage planetary gearbox that launches a toroidal ringover 3000 RPM! The design is 100% 3D printed; all pieces press fit together and no additional hardware is required.
The gearbox used in this design is modular and will be released as it's own series soon™, if you have any thoughts or feedback please share so I can continue to improve the design!
Three stage planetary gearbox with 1:48 gear ratio (overdrive)
0.75mm gear module for ultra-smooth performance (24/72 teeth)
10mm hex driver for connecting gear stages
Toroidal ring design with four blades (1.2mm thick) available in three sizes
100mm diameter, 150mm pitch
125mm diameter, 175mm pitch
150mm diameter, 200mm pitch
Printing tips
All prints pictured were printed using Bambu Basic and Matte PLA
For best results run flow rate calibration and thoroughlyclean build plate
The launcher gears are available in two print profiles with the following changes to the standard 0.20mm profile:
Arachne wall generator
5x top and bottom walls, 25% infill
75 m/s inner and outer wall print speed
The toroidal rings are available as a single print profile with the following changes to the standard 0.20mm profile:
0.6mm line thickness, Arachne wall generator
75 m/s inner and outer wall print speed
The launcher housing prints with the standard 0.20mm profile.
Launcher Parts
Launcher Gears
SunGear24.step [3x]
PlanetGear24.step [9x]
PlanetCarrier24.step [3x]
RingGearDouble.step [1x]
RingGearLid.step [1x]
RingDriver.step [1x]
GearDriver.step [1x]
Launcher Housing
HousingBase.step [1x]
HousingRingLid.step [1x]
HousingCarrierHolder.step [1x]
HousingCarrierThreads.step [1x]
Toroidal Rings
ToroidalRing100.step [1x]
ToroidalRing125.step [1x]
ToroidalRing150.step [1x]
ToroidalRingDriver.step [1x]
ToroidalRingLauncher.step [1x]
Launcher Assembly (Gears + Housing)
Assembly the planet carrier with three planet gears and one sun gear as shown below. Repeat for all three planet carrier assemblies.
Use the shorter hex drive to connect two sets of gears. Align both planet carriers and hold them with one hand while holding the double ring gear in the other hand and slowly turning as you close the gear; once closed insert the assembly into the main housing to hold secure. The gears should spin freely; if they don't remove the gear assembly and repeat this step.
Use the longer hex drive to connect the last set of gears and then assemble with the threaded cap as shown below.
Carefully mesh the single ring gear with the planet gears taking note of the 2mm flat section that is positioned towards the main gear assembly as shown below. Use the same method of rotating whileslowly closing and covering with the cap to hold secure.
Done! The assembly should spin smoothly with the output shaft making 48 rotations for every one turn of the input knob. Performance depends on printer tolerances and filament used; for best results use the include print profiles with Bambu Studio (supports many different printers). A bit of lubricant can also be added to the gears to improve performance.
Toroidal Ring Assembly
Insert the hex drive into the interlocking driver; the clearance is tight but it should be a snug fit.
Insert the assembled driver into the output sun gear, the fit should be the same.
If the driver does not stay secured when launching the ring a small amount of CA glue can be use.
Changes
v1
Initial release; files now available in v1old folder
v1.1
Updated print profiles with improved settings for gears and rings
Improved single color print profile, fits on A1 mini and objects are laid out to allow skipping
Improved clearance of gears and overall meshing
Updated toroidal ring to use the same launcher as the mini rings
Print profile includes 3 sizes (100mm, 125mm, 150mm)
Updated assembly instructions to have fewer steps with a GIF for each one
v1.1.01
Added new section for template designs intended for remixing
I see a bunch of likes on this so just wanted to follow-up and say you're more than welcome to publish your design and link it here for others to print if you'd like to since it's just using a standard 10mm hex drive 😀
The main reason I don't currently allow remixes is I would prefer to gather feedback and improve the original model rather than have a lot of remixes with small changes and low compatibility. Many parts of the design are modular and I used standard sizes where possible so cool stuff like this was always intended but ultimately I plan to release some "template designs" such as the threads, hex driver and cap for the ring gear that allow remixes for even more possibilities, stay tuned!
Can you upload a video of you putting it together? In your steps, when you place the blue set of gears on top of the yellow ones, if I push mine down all the way, put the ring gear around it and then the cap, it is VERY hard to turn.
If I dont push the blue set down all the way onto the hex drive (or not push the hex drive all the way into the yellow one), the ring gear goes around the blue gears much easier. When I put cap on, its easier to turn but looking at your video, you held it in one hand and turned it. I still cant do that.
Also the black cap next seems to want to sit flush with the other piece, it always wants to kind of pop up.
I printed everything with PETG.
To try to explain it better with photos, if I assemble it as you say. and I do whats in pic 1, and then pic2, notice how far down the green gears are from the cap. if I put the green gears in the cap first (pic 3), and then do pic 4, it spins easier but notice how the black cap doesnt sit flush.
This is amazing. Just saw your post on reddit last night and printed all the parts. Fully assembled now and works like a charm. I had a little more friction on one of the sets of planetary gears than the rest but added a little bit of silicon lube... same stuff I buy for the printer itself and everything functions perfectly after working the lube in. I respect the extra care take in the design and positioning of the parts - all of the hex drives are positioned sideways to give them optimal structural integrity and avoid sheering forces along layer lines.
I see other comments about grinding and cracking noises... no such issues here, but a little lube was the trick for me. Prior to adding lube, the gearbox seized up - likely due to the single set of planetary gears with high friction. I love this design and plan to use it as a learning toy for nieces and nephews so I'll likely play around with other materials like PLA-CF for the gears to see if things improve a little more in subsequent prints. if i can get a working system without lube, I'd like to gift it unassembled so the kids can learn about gear ratios.
Other thoughts to avoid need for lube... if one or more of the planetary/sun gear sets doesn't spin freely when assembled, you're going to have bigger problems with the fully assembled system. You're better off reprinting another set than trying to assemble it with a known problem like this. That little bit of friction is going to be compounded when fully assembled.
Not sure exactly... somewhere around 6-8 meters if i get it really cranked to a full rotation before it releases. Two story house and I'm worried about it getting on the roof if I'm not careful.
how do you fly it even that far? half the time the blade doesnt come onff ( even though theres nothing keeping it on, it just doesnt get enough torque or whatever... my prints 100 eprcent clean too, everyhting moves just fine. it just sucks
Awesome design!
Only complaint is it’s not very user friendly as it does not give you very much space between your hands to spin the gears.
I modified the Housing base by extending it 70mm… Much more easier to lunch and spin the gears with the much needed spacing between your hands when using.
Since the author says no sharing of derivatives or remixes of his design, I can not share this mod… although the raw files are .step files, so they are easy to mod if you want to also perform this mod!
Again, Awesome design!
If I remove this accessory, the gear can rotate, but when I install it, the gear cannot rotate. There is no problem with the clearance and engagement between the gear and this accessory. I don't know why
The double ring gear is supposed to stay static while the planetary gears rotate on the inside. Only the single ring gear is supposed to move as it is on the part you twist.
Sorry, I can’t exactly understand what you are saying, but I will try my best to help what I think the problem is. I will add a few pictures showing how it is supposed to rotate. Strip the assembly down to just the large casing and the first two stages. Try to rotate the organe gear stage by the triangle top as seen in the image. When you do this the planetary gears should rotate around the sun gear in the orange and green stage since they are connected by an axle. If they do not move then your gears are not meshed correctly or the print quality is bad causing them to not fit together. You can also try to lubricate the gears which is pretty much nessacary for good function, but even then I could rotate my gears fairly easily without lubrication. Next, make sure you secure the last stage on top with the axle before you screw the cap on.
Works great for me too. I used all your default settings except I printed on an X1C and moved each color to a different build plate. I also separated the propeller from the other two components. I did reposition the hex drive for the propeller though... it was originally positioned with an edge rather than a side touching the build plate - I repositioned it so the edge was touching flat - not sure if this was intentional or an accident in that file. Printed everything in Bambu basic PLA on a cool plate with glue stick.
Thanks for the reply James, there was a brief window when I was working on changes and the profile had the drive on its edge like you're saying but it should be fixed in the latest profile. Glad the rest of the print turned out well!
I've printed a 66% size model on P1S with 0.2 nozzle and PLA Matte. This took some tinkering as opposed to the regular size - slow down the print, increase 1st layer temp 220 -> 230, couple of tries. Some frustration, 7 hours and a smidge of WD40 later I have a working mini version!