“What a stupid idea. I like it!”
Somebody once said.

Where I got the idea #

A friend and I thought this meme was ridiculously funny.
Not long after that the challenge was born to build a device that shoots pasta.

3D printing was an obvious choice, since we both have either our own printer or constant access to one.

Operating principle #

Accelerator stage #

The individual pieces of pasta are quite fragile and shatter when they are subjected to a sharp impact.
Because of this a hammer system was already not really suitable.
The macaroni are also hollow, so a compressed air system was also not feasible, apart from it probably being rather complex anyway.

In the end a flywheel based system was chosen.
Some NERF guns also use this approach.

With NERF guns the ammo is the soft part, but in this case the ammo is hard and needs to be gripped gently.
To achieve this, a TPU sleeve (black star shaped thing) was put over the motors to firmly grip the macaroni, but not squish it to pieces before it exits the gun.
For the motors two small rc brushless outrunners were used, in combination with two 12A ESCs.

This is way overpowered and can’t really be used at 100% speed because it will likely break it self to pieces and is also way too scary to still hold in your hands.
Even in its current tuned down state the motor still makes quite some noise.

Magazine #

The magazine is kept rather simple.
On the inside there is a sled, that can move up and down freely.
It is pushed upwards with the help of two rubber bandy which are guided in individual groves to be out of the way.

On the upper side, there is a small dimple. It is used for a ball spring insert in the main body, so the magazine clicks into place and is held there firmly.

Trigger mechanism #

This was a tricky part where I had to make a couple iterations.
The initial idea was to smack the macaroni out of the magazine in between the flywheels.
This would mean that the gun would have to be cocked for every shot and the pasta might get damaged by the smacking.

After some tries I ended up with a simple push mechanism that gently pushes the macaroni out of the magazine until the flywheels catch it. While the macaroni is pushed forward the remaining ones in the magazine are constantly pushed upwards, but can’t move because of the carefully designed pushrod.

The trigger is pulled back by a spring attached behind the pushrod.

Arduino and wiring #

The arduino has the sole purpose of generating a PWM signal for the ESCs at the right time.
So the code for it is rather short and simple.

Inside the hollow handle, there is a 3s 450mAh LiPo battery I had laying around. Power is routed from the battery via a main switch (red switch on the side) directly to both ESCs.
The arduino is supplied from the 5V supply voltage generated by one of the ESCs. This supply normally powers an rc receiver.
On the side of the housing there is a toggle switch to start and stop the motors. Its signals are just routed to a GPIO on the arduino.

How well does it shoot? #

It actually shoots rather well. The accuracy is pretty shit, but force wise I would say it’s comparable to a BB gun.
If you shoot your own hand it zings a bit, but you probably need to shoot directly into someones eye to do some damage with this.
Currently the macaroni is just yeeted out the from without any spin or stabilization. It therefor tumbles quickly in the air.
For a future version the motors could be tilted to each other to give the macaroni some spin.

All the CAD data and arduino code is on Github.
If you built one or got inspired to construct your own, please send me a picture of it!