That's a very cool project. Some leds have built in resistors. Maybe your red ones do. You can also buy flashing leds and color changing leds but they also need an inline resistor. I think an N20 gear motor would be a good match for your project as they are much smaller but have good torque and low current draw. I use them in my projects. You might consider 3 AAA batteries in a Cylindrical holder for a 4.5 Volt supply. The batteries will last a lot longer than the coin cells and I doubt you will need the 15 Volts. Your circuit is a series circuit and all the current for the motor runs through the led and the led resistor. Probably not a good ideal. To get around that you could make a junction block with 3 contact points. This will allow you to make a parallel circuit. Then you would have the led and resistor on one branch and the motor on another branch. I think you will really enjoy learning electronics. It goes well with the 3D printing hobby.
Well done Lexie, this is great! Did you try the red LED last? I think the reason could be that the batteries got damaged during your first few tries with the white LEDs. Connecting an LED directly to 15 volts creates high current flowing through both the LED and the batteries. When you fried the LED, you may also have damaged the batteries to the point where they can’t supply that much current anymore, saving your red LED. 😊
Yeah, I did use one to measure the voltage after frying my LED and motor lol. I honestly had no idea that stacking batteries made the voltage higher. Learning by trial and error.
