As far as I know, no one has ever attempted to create an Aperture Science Quantum Tunneling Device (The Portal Gun from Portal) with a blowback mechanism. So I created a very rough prototype to remedy this.

There are plenty of recreations of the iconic item from Valve‘s masterpiece ranging from the official Neca Replica, to handmade props to 3D printed designs. Most designs include lights and sounds operated with toggles or tactile switches. However, all of them are static and do not move when firing. Personally, I find that the lack of tactile feedback makes these props feel like toys that don’t quite capture the feeling of the game.

In the advertising materials as well as in 3rd person (which can only be accessed through mods and console commands) the portal gun is shown to have no moving parts. However, in the default 1st person perspective, the portal firing animation clearly contracts the device after each shot. This is especially obvious when exporting the models and animations in Blender and viewing from the side.

The blowback mechanism used was inspired by Hasbro’s Transformers Robot Weapons Bumblebee Plasma Cannon (discontinued). Pulling the trigger of an internal handle extends the front of the cannon until it reaches the end and snaps back to its original length.

However, this mechanism had to be heavily modified for my design. The portal gun contracts instead of extending when firing so the mechanism had to be reversed; I used a rack and pinion system instead of a lever so that the handle of the device looks the same as the game model; I used rubber bands instead of springs.

As this was only a prototype, I used EVARATE’s Portal Gun V2 as a base and only remodeled the body, handle and middle channel. I also only printed the major pieces of the model (small & large cover plates and nozzle) to achieve silhouette of the device as I plan on revisiting this project in the future.

In testing, my prototype flexed considerably as it was made almost entirely of PLA; the bending made the mechanism unreliable. A full replica would weigh even more so some sort of reinforcement and linear bearings would be necessary. After surveying for feedback, the another point raised was that the reciprocating motion was too fast. Solving this would involve a dampener of some kind such as a gas strut. Regardless, it appears that the mechanism needs be completely restarted from the ground up.

On another note, while EVARATE’s model is aesthetically pleasing, there are some improvements I would like to make. When overlaying the game model, the proportions are a bit off and I would like my replica to be as accurate as possible. The construction of the model requires glue on almost every joint. Ideally, I would like the model to come together using proper threaded fasteners for easier repair and maintenance.

Not only is the mechanism unreliable and only successfully firing every 1 in 5 trigger pulls, but the model is impossible to assemble. I overlooked the assembly process and had to carve pieces out with a knife to make them slide into each other.

This project will be shelved for the time being and I will not be publishing the files but I plan on releasing my final design in the future.