Desktop Shooter Game

Growing up, a zombie shooting game was one of my favorite arcade games. There was a blaster that shot physical balls the size of tennis balls to shoot down zombie targets. Normal shooting games are already a blast, but the experience becomes truly exhilarating with actual flying projectiles.

For this instructable, we will create a miniature, but similar, experience. Anyone with access to a 3D printer and an ink-writing pen can create this design. There are built-in joints so not even glue will be required.

This instructable is almost entirely based on the 3D modeling software Fusion 360. If you are completely new to 3D modeling, the free "Learn Fusion in 90 Minutes" course on the official Autodesk website can give you all the required skills.

There will be reference stl files for each component and some f3d/f3z (fusion 360) files with a traceable timeline. The steps are highly detailed in the modeling process.

3D Printer + Filament

Fusion 360 (Free for Students and educators)

Slicer Software (Cura, Free download)

Spring (Pen Spring)

The spring is the core driver of the shooting mechanism. When compressed, it stores energy in the form of potential energy. Once released, the spring releases all the stored energy as kinetic energy, which can launch objects. Springs have many uses and can be found in many modern-day objects such as cars, clocks, and pens. For this small-scale instructable, we will repurpose the spring of a used pen. To remove the spring from a pen, unscrew the cap, remove the ink cartridge, and - if necessary - bang the pen against a hard surface to force the spring out.

Now that we have the spring, measure the width and length as a reference for the blaster model. My spring was 0.55cm in width and 2.5cm in length.

(Note: I am modeling with centimeters)

Part 1: Barrel

The barrel is where the projectile will be launched. It ensures that the projectile will stay on the path when shot.

Create a sketch of two overlapping circles. One circle's diameter is around the spring's diameter (0.5cm) and the other circle's diameter is slightly over the chosen projectile diameter (1.5cm).

Extrude the outer portion of this sketch to a length noticeably greater than the spring length (4cm).

Then, create a sketch slightly smaller than the bigger circle (1.25cm) and do a cut extrude to the midpoint of the circle. The uncut portion will be where the spring resides and the outer portion will be where the projectile will stand.

Create a 0.7cm diameter circular sketch in the internal portion of the barrel and cut extrude to 0.1cm away from the outer face. This gives an area for the spring to be compressed without falling out of the barrel.

Part 2: Projectile Loader

This allows the player to easily load in projectiles instead of pushing a projectile through the front of the barrel.

Construct a tangent plane at the cut portion of the barrel. Create a sketch of a square the same width as the barrel (1.5cmx1.5cm) at the end of the barrel and extrude it to the barrel.

Create a sketch plane on the front of the shape made from the previous step and create a trapezoidal shape with the top(2.5cm) bigger than the bottom(1.5cm). Then, extrude this plane to match the length of the previous step.

Use the shell feature to hollow out this shape and leave it with thin walls. Select the top of the trapezoidal shape and the inside of the barrel as the two faces for the shell.

Not only did the shell hollow out the projectile loader, but it also hollowed up the interior of the barrel. To fix this, extrude the inner face of the other end of the barrel to the outer face of the smaller part of the barrel.

Part 3: Blaster Attacher

This part will later be used to attach the blaster onto a rotating platform.

On the other side of the barrel, construct a tangent plane and create a square sketch smaller than the barrel diameter (1cmx1cm). Extrude one side of the sketch to the barrel and extrude the other side 1cm down.

Create a sketch of a 0.5cm diameter hole 0.5cm away from the bottom of the previous extrude. Extrude this as a cut through the object.

The player will pull back this stick, which will compress the spring. When the player lets go, the spring decompresses, launching the loaded projectile.

Part 1: The Stick

Create a sketch of a 0.6cm diameter circle and extrude it by 0.25cm.This is the base of the stick that will push the projectile.

Sketch another circle on top, smaller than the spring diameter(0.3cm), and extrude it to be longer than the barrel (6cm). The spring will later go around this part.

Apply a 0.2cm fillet to make the shooting stick less likely to break.

Construct a tangent plane near the top of the stick. Create a sketch and extrude four 0.1cm depth x0.5cm height cuts into the stick. This will hold an attachment that will prevent the shooting stick from flying away when the player shoots.

Part 2: Stay in Place Attachment

Create a 1.2cm by 0.5cm rectangle sketch and extrude it 0.3cm. Then, cut out a 0.2cmx0.5cm rectangle in the middle and a 1.2x0.1cm rectangle along the body. This will make it so that it fills the holes of the stick.

Move the attachment to fit onto the stick. Save the attachment as a separate part as it will be printed separately.

The Target Zone is the area where all the targets reside. Targets will be tilted onto a bar. When they are hit, the targets will rotate backward and fall.

Part 1: Structure

Sketch a 4cm long triangle at a 20-degree incline at the origin. Then sketch a 0.5cm wide and 8cm tall rectangle at the base of the triangle. Extrude this by 10cm.

Sketch and extrude a 0.5cm thick wall on both sides. These walls will prevent the ball from falling out.

Sketch and cut-extrude two holes into the walls at 2.5cm increments. These will hold rods that contain the targets.

Sketch and cut-extrude a T-shaped hole into the base using two 2cmx4cm rectangles. This will allow the target zone to attach to the ramp we will make later.

Part 2: Target

Sketch a 0.5cm circle surrounded by a 0.75cm circle. Have vertical lines coming out of the horizontal endpoints of the circle. The height of these lines and the extrusion distance of the sketch can be adjusted to change the difficulty. I used 1.5cm length lines with a 1.5cm extrusion distance.

Add fillets to the target to make it rounded.

Part 3: Targets in the Target Zone

Create two 0.475cm diameter and 12cm long rods. The diameter is smaller than the holes previously made as this rod will have a loose fit inside the holes.

Make each body a component. Create 3 copies of the target and use rigid joints to connect the targets to the rods.

Use rigid joints to connect the main rod to the structure.

Add two rectangular supports for the targets to rest on.

Shooting balls is fun. Collecting balls isn't as fun. With a ramp, we can use the power of gravity to bring the shot balls back at us. Modeling the collection ramp assembly on the target zone file will make it easier to reference sizes.

Part 1: Ramp

Create a ramp of the desired length at around a 20-degree angle from the target zone. My ramp was 10cm long, but the length can be adjusted based on the desired difficulty. Make sure to add a vertical end to the ramp to later attach the blaster base to. Extrude the ramp as a new body so it will not be part of the target zone. Having the ramp be detachable to the target zone allows for changeable ramps and easier assembly.

Create ramp walls by using the target zone as a sketch guide. Add a vertical section at the end to later connect the blaster platform. Disable the target zone when extruding so the ramp and target zone don't combine into one body.

Extrude a T-joint for the ramp to connect to the target zone.

Extrude another T-joint on the other side which will connect the ramp to the blaster base we will make in the next step

Arcade shooting games often have the blaster connected to the machine. That is the case for our design. The blaster can rotate vertically and horizontally so the player can easily aim at all the targets.

This part will also be created on the same file for easy reference.

Part 1: Box

Extrude a rectangular hollow box out of the ramp. This is the base the blaster will be attached to.

Cut the T-joint into the box so it can connect to the ramp.

Part 2: Holder

Create a circular base with 2cm tall rectangular sides. Cut-extrude a 0.5cm diameter hole in them.

Create a 0.475-diameter rod longer than the circular base and move it into the previously created hole.

Create a pin to hold the base in place. In the physical model, the pin will be placed in before the rod is inserted. The pin connects the blaster to the base while also allowing for rotation in the horizontal plane.

Now that we have all the models we need, it is time to create a file that has all of the components. This will represent what the actual printed model will look like. Most of the components were already made in the same file so there is not much to import.

Part 1: Assembly

Import the blaster design and line it up with the supporting rod on the blaster base.

Insert the shooting stick into the blaster

Part 2: Projectiles

The blaster we designed shoots out balls with a diameter of 1 centimeter. These can easily be made with the "create form" feature of Fusion 360.

This instructable guided you through creating a basic desktop shooting arcade game. You can easily add your fun twist to this design.

Some ideas for you to explore are:

Adding another section of targets

Extending the ramp length

Adding another blaster for two people to play at once

And anything else you can imagine

Now, it is time to bring ideas into reality. Any slicer software will work. I prefer using Cura as it has pre-set printing profiles for most 3D printers and is easy to learn. Make sure to print in the orientation that will give the most component strength and use the least support.

For example, this is the shooting stick printing orientation:

There would be less support if it were printed standing up. However, 3D prints are weakest in the direction of the layers. Therefore, it is sometimes worth printing more support to guarantee a stronger part. For the moving parts - the blaster, shooting stick, and shooting attachment - print at 50% infill. The rest of the parts can be printed at 25% infill as they will not have much force acting upon them.

There are some areas where removing support would be an extensively challenging task. For example, removing the support inside the barrel of the blaster would be extremely difficult. Therefore, it must be printed facing up.

Use these practices to print out the rest of the parts. Make sure to print out multiple copies of the targets and rods. Each component has to be printed separately. Once all the parts are printed, assemble them to resemble the final model in step 7. To assemble the blaster, insert the thin end of the shooting stick into the spring and then put those two into the blaster. Then, place the holding attachment onto the extruding end of the shooting stick.

Now that you are done, enjoy your new desktop arcade game!