Electric Propeller Launcher

I'm Matthew (hello), and I go to RGS, Newcastle. For my project I decided to make a toy propeller launcher. This was to use an electric motor instead of any gear mechanical designs. The main problem when designing this was the propeller clip that needed to release the propeller when its rotational speed was greater that motors. This means that the flight height could be controlled by a potentiometer, or how long a button was held down for. I kept trying to make one like out of this video by Tom Stanton, however, this was really difficult to modem in fusion, and I found that they were hard to clip onto the propeller. Eventually, I came up with the idea of an internal nut and bolt design, and I used the coil tool in fusion to make it.

Important: I struggled with getting the propeller very high because at all because the rubbish power supply kept cutting out when too much current was drawn. For best results, use a li-po battery (but be careful they are scary and don't short them please), or make the propeller and motor much smaller. I'm an idiot and didn't think of this until after I printed it. However, I did use a big motor, propeller and variable power supply before having to leave school, and it went really (really) fast. Unfortunately I was still in the low ceiling-ed DT classroom at that point so ill admit that was my bad 😐. Verdict: use a smaller propeller and motor if you don't have a high amp power supply (or use a powerful battery).

For the build you will need a 3d printer, laptop and soldering iron. A hot glue-gun is very useful but I guess you could use superglue or something similar. Also, I couldn't find the motor that I used online, and you may choose different components, so being able to change some of the sketches or parameters in fusion 360 may be very useful.

The motor was an 8volt brushed motor, and I used a 9 volt power-supply - I realise that this is overvolting the motor, but in short bursts you should be alright. The design was printed for a potentiometer that looked awesome, but after wiring everything together I realised that it was broken :( so instead I had to use a tiny push button and keep it in the hole with lots of hot glue. Crude, but worked and school was closing so needs must. Also, a bullet socket it what I used because I didn't have a 2s li-po battery, but if you want a challenge, then a portable version of this would be a fantastic project, and I might try that once Christmas comes around.

Print all the files. Remember to change them to your components. :)

Hot glue the plug, and then wire up the plug, button/potentiometer, and motor in series. Quickly test if the circuit works but be careful that there are no exposed wires that can touch together. A tip is to keep the stripped ends of your wire quite short, and use electrical tape if there is any possibility of short circuiting your power supply. Be careful with the hot glue gun and use googles and apron when soldering. Also soldering irons are hot (ik), so please keep you work area really tidy use the cradle thingy.

Next glue the motor in place - be careful as you don't want the glue to get inside of the motor. Also hot glue is hot 🙄 and also sticky 🙄🙄; it will hurt if you touch it. The little latch thingy is friction fit, so when forcing it one, use a thick metal rod or something similar to hit the shaft protruding from the other end of the motor. Don't just push with the motor as you might bend the shaft or ruin the bearings.

We are almost there... Glue the little cap and fit it in the motor tube. Also cable management it for dull people so just shove the excess wire in the tube as well (👉ﾟヮﾟ)👉. You might notice that the button really doesn't fit the hole in the picture. Don't be like me - test that your components work before changing the print to incorporate them. I'm really sad about that potentiometer still - it looked awesome. Also If you do use one of them remember to measure the resistance of the rest of the circuit as well so the potentiometer is not too resistive ect. Finally wait for the glue to dry and your done!