Crotalus

Has anybody ever thought of making a 3d-printed disc?
Would be pretty easy to make one in sketch up.

3d printing would be horribly expensive and inefficient for this task.

That would be the most ideal case if 3D printing was cheaper. The 3D printer I run is capable of printing hard materials and soft materials simultaneously (as well as the full scale of hardness between them). It can print the entire disc in one go without having to print each soft and hard component separately. It would take 30 minutes to print 1 disc and probably 40 minutes to print 15. It's not a linear progression as you can see. The cost is probably around $0.50 a gram, conservatively.

EDIT:
Here's a weird idea. What if we made our discs with some sort of ferrite element that responds to a magnetic repulsion effect as it leaves the gun? This could potentially increase the force on the disc as it leaves the barrel; it might even provide extra spin if designed a certain way. It would also give the disc more weight to handle the force of the more powerful springs we will eventually mod into the gun.

Very slick!!

One suggestion I would make is to consider the implementation of a momentary or rocker switch that is pressed by the flinger arm when the blaster is primed. It would add that extra bit of flair.

That is a great idea; I will try that. I think I will mount it in parallel with the rocker switch so the light can stay permanently on or only when primed.

The top is essential to flight. The reason they glide so well is large horizontal surface area, and small vertical area. Does a piece of paper with a huge hole cut into it fall faster than a normal sheet of paper?

What if they were more like washers instead of Frisbee shapes? What if you could shoot a stack of three thin discs at once instead one thick disc? Aerodynamics is not my thing, especially with these projectiles that depend more on aerodynamics effects than a simple weighted stefan dart.

I don't know if this has been specifically mentioned yet, but it seems like the only reason the discs have a top and bottom side is because of the safety mechanisms. On the Proton pistol, there are safety mechanisms responsible for preventing firing if no disc is in the breech. The top safety mechanism detects whether or not the disc is upside down. If this safety mechanism is removed, you can fire ring shaped projectiles alongside of Frisbee shaped projectiles.

I think this can greatly simply the homemade discs if you don't need to worry about creating a top surface. You just need to create a ring.

I choose to use red LEDs. If you want to use other colors, test them out with the orange plastic first. Certain colors like blue and green aren't as visually appealing when they glow through the orange plastic. However, you can mount these LEDs so they shine like a flashlight through the barrel instead of glowing through the cowling. This effect is very striking regardless of the color you use.