My first project’s speed control module was originally designed to be inside the casing, but I realized later that the drawing was wrong and the module’s casing was too small. So I used pliers to remove it.

Materials:

1. 80×80×10 fan, 12V.

2. Speed control module, costs a few bucks on Pinduoduo.

3. Connect the 18650 battery cases in series.

4 x 18650 batteries, section 3.

5. Two screws, they should be M3. I just picked some screws randomly.

6. Carbon filter.

For the first piece, if the feedback is good, I can make some improvements. This one works fine for me, so I didn’t redraw it.