DIY 15$ Air Blower (200+ Km/h)

I saw this fan in a YouTube video and decided to buy one for €15 on AliExpress. I then designed my own case for it, and it outperforms most expensive blowers on the market. The highest wind speed I measured was almost 210 km/h (with fully charged batteries).
works with both 21700 and 18650 Batteries with including adapters.

Files & Modifications

I’ve included the STEP files as usual. There’s also a nozzle template. However, since models uploaded as "Exclusive Model" don’t allow remixes, I want to clarify: You are ALLOWED to modify and upload nozzle variations—just leave a comment and include a link to your modified version (Nozzle Only).

Important Safety Information

Read the instructions carefully!

• The fan pulls 25A (220W) at full speed. Using the wrong batteries or wires can cause melting or worse.
• NEVER insert the batteries the wrong way! If the polarity is reversed, the fan will go up in smoke (don’t ask how I know).

Building Instructions

Printing the Parts

Print all the parts in the material and colors of your choice—I used PLA.

Fan Preparation

1. Remove all wires from the fan’s PCB and replace them with slightly longer ones:
   • 100mm for fan power wires (should be around 1mm²)
   • 100mm for the potentiometer and button wires (thin wires like 0.14mm² are fine)
2. After soldering everything, test the fan to ensure it works before proceeding.
3. Carefully push the fan into the housing, making sure all PCB wires are routed in the same direction to avoid airflow obstruction.

Battery Contacts

• I used 30mm x 8mm x 0.5mm copper strips as battery contacts.
• Cut them to size and solder the power wires to the strips.
• Use heat shrink tubing to cover the top 8mm where the wires are soldered.

Assembly

1. Install the Battery Contacts
   • Push the copper strips through the slots.
   • Slots are available on both sides—choose the one that works best for you.
   • Ensure correct polarity (positive and negative) as marked on the battery tray.
2. Attach the Potentiometer
   • Apply a drop of super glue on each side of the potentiometer.
   • Insert it into the case with the wires facing downward.
   • Immediately attach the knob to ensure smooth rotation before the glue dries.
3. Modify & Install the Button
   • The button is modified to momentary (hold-to-run) mode (if it isnt already):
     1. Open the back of the button.
     2. Remove the clicking mechanism.
     3. If a clip breaks, secure the back cover with super glue.
   • Feed the button wires through the correct hole and solder them to the button.
   • Use heat shrink tubing on the contacts.
   • Push the button into place—it’s designed to be a press fit, so the included plastic nuts aren’t needed.

Parts List

Questions?

If you encounter any issues, please feel free to contact me on Discord: StriK3FoRC3#0001 Additionally, you can join my Discord Server for more support.

Donate if you want, need more Filament for other Projects/Prototypes ;)