This is a fully 3D-printable hand-cranked bubble machine that works without electronics or extra parts. Just print, assemble, add soap solution, and turn the handle to create a stream of bubbles.

⚠️ Please, before starting the full Bubble Machine print, slice or, if you’re using Bambu Handy, print  Slicer Test Model. This brief check ensures your slicer handles supports, modifiers, and arachne wall generator correctly, saving filament and time.

🔧 Key Features:

• Fully 3D-printable, no extra parts needed
• No batteries or motors — runs by turning the handle
• Eye-catching design with visible moving parts
• Works indoors and outdoors, even in windy weather
• Can be used handheld or placed on a table
• Easy assembly — even a first-time build takes less than 20 minutes

🛠️ Before You Start

• Always dry your filament before printing
• Clean your build plate carefully before printing, especially for the Bubble Wand Wheel. (I clean additionally using ethanol), You can also follow the advice.
• Follow the Assembly Video Guide for proper installation
• Lubricate the fan shaft and transmission shaft during assembly; it is important to avoid the shafts overheating.
• Read the FAQ if you want to learn more about how the model was designed and how to use it

📽 Assembly and use guide:

🧰 Assembly Tips

• Before inserting the shafts into the body, pre-thread the nuts (or screws) onto them a few times — this makes it much easier to tighten them later when space is limited
• Make sure all moving parts rotate freely after assembly — do not force anything

Mini Version 50%. For Experts Only

Mini 50% version optimized for 0.2 mm nozzle printing. Print it only if you're ready to tinker.

This profile is for the redesigned mini version, not just a simple scale-down. Several parts were reworked to keep the mechanism functional at this size:

• The Fan Gear was changed from 16 teeth to 8 teeth, which doubles the fan speed and helps compensate for the smaller fan diameter.
• The transmission gear position was adjusted,
• the handle shape was simplified so fingers fit better,
• Wall thickness was increased in selected areas to preserve strength.

This model requires very delicate, precision-level assembly. Some parts are fragile and may break during assembly if handled roughly.

Because the clearances are extremely small, the result may vary even on the same printer when using different filaments. Some moving parts may require X-Y contour/hole compensation in the range of 0.01 to 0.03 mm, depending on your printer and filament.

Before final assembly, first connect and test all parts outside of the Main Body to make sure the clearances are correct.

It is especially important to carefully remove all support residue from the Main Body holes for moving parts. Poor cleaning in these areas can prevent proper movement.

If the parts are fitted well and assembled carefully, the finished model works reliably without further issues.

Tested with:

• Bambu Lab PLA Basic
• Bambu Lab PETG HF

I printed 6 models on 3 different printers. Most parts worked without modification, but some parts required X-Y contour/hole compensation, sometimes in opposite directions depending on the printer and filament. The parts that may need tuning are:

• Transmission Gear
• Fan Shaft with Gear
• Fan
• Main Gear

❓ FAQ

Q: What material should I use to print it?
A: You can print it with PLA, but PETG is even better — it makes the parts more durable. PLA is still fully sufficient if printed well.

Q: Are there some specific parts you would suggest printing in PETG? (Thanks @user_3157994991 for the question)
A: If you want to achieve greater reliability, print in PETG the “Fan Shaft with Gear (16 teeth) with gear” and the "Transmission Gear with Shaft (80 teeth)"; all other parts printed in PLA worked well even in early versions, but lubricate the shafts anyway.

Q: Can I print using 0.6 mm nozzle?
A: NO! My print profiles are adjusted to printing using 0.4 mm nozzle only. There was an attempt to do it, and it failed. Thanks to zakorkaz for sharing their experience.

Q: Why is the Bubble Wand Wheel hard to print?
A: It prints fine if your build plate is clean. The part has thin features, so make sure to clean the plate thoroughly before printing.

Q: How does it work?
A: The handle drives a gear train that spins a fan and a bubble wheel. The wheel picks up soap film from the reservoir, and the fan blows bubbles through the rings.

Q: How fast should I turn the handle?
A: Maximum 1 rotation per second. Faster spinning won’t improve performance and may cause the fan shaft to overheat.

Q: Couldn't the airflow be improved with a shroud or other design tweaks?
A: The goal was to create a visually striking bubble machine with fully visible gears and moving parts, without using purchased components like bearings or electronics, and powered purely by hand. I managed to combine all these goals without sacrificing performance.

Q: Don't the horizontal shaft holes in the body cause extra friction? Wouldn’t it be better to print bushings vertically??
A: I understand the concern — in early versions, I designed the holes to print vertically. But during a test iteration (mainly to check part fit), I printed the body with horizontal shaft holes, and surprisingly, it worked much better. Friction decreased, and the fan shaft stopped overheating. (Earlier, a PLA shaft had melted from friction — I had to switch to PETG.) The result was so good that I kept the design. It also allows printing the body as a single part, which is a big plus!

Q: What’s the fan speed and gear ratio?
A: The gear reduction is 1:45. At 1 crank turn per second, the fan reaches 2700 RPM. Effective operation starts at around 2000 RPM, so slower cranking still works well.

Q: How much liquid does the soap reservoir hold?
A: For proper operation, pour in 150–200 ml of bubble solution.

Q: Suddenly, the crank became hard to turn. What’s wrong?
A: This usually means that the fan or transmission shafts have overheated. It happens if you crank too fast or the lubrication has worn off. Apply some lubricant to the shafts and keep the speed under 1 turn per second. Forcing it may deform the plastic.

Q: How long did it take to make this model?
A: About three weeks of all my free time. I printed 6 different versions before I was finally satisfied with the result. It was a real challenge to combine functionality with a visually striking design, ensure stable movement without overheating, and achieve optimal airflow — all without using a shroud or turbine-style fan. But I managed to get it all working smoothly.