The next part is the design of the case and this took some time to make it small, compact and also look good. I’ve tried to copy more or less the online design but instead of 2 batteries, I will make mine a bit bigger for 3 batteries and more power. I've made the space for the motor. Then the space where the batteries will go. I added the push button. And below everything I will add the small BMS with a connector for charging. You can use a balanced BMS and add your own USB connector or you can find on AliExpress a BMS that already has a USB connector if you want. At the air output I’ve placed a hole for a magnet. And then I’ve made the tip funnel which will also have a magnet so we can merge them together. And the design is ready, but this is like the forth version. I had to make a few attempts until I got the right size and shape.