3D Printed Katana

In Ms. Berbawy's Principles of Engineering Class, we have a long term project called a SIDE Project where we get to decide our own project that we're going to work on throughout the year. The project I decided to do was to make a 3D printed Katana. The katana in this instructable will be based off the sword "Faith" from Nier Automata.

The reason why I chose to make a 3D printed katana is because I was inspired by one of the previous year's project that made a 3d printed sword. I was also inspired cosplay props cosplayers would make on their social media platforms.

For this katana I used Fusion360, Prusa Slicer, Adobe Illustrator, and CURA Slicer, then used a Pursa Mini+ and a Lulzbot Mini 2 to print out the parts.

Materials

• 3D Printer (Pursa Mini, Lulzbot Mini)
• Filament (PolyLite Black PLA and Geeetech Silk Metal Filament)
• 7/16 inch diameter Wooden Dowel
• Dowel Cutters
• Paintbrushes and Acrylic Paint
• Hot Glue

Software

• Fusion 360
• Prusa Slicer
• CURA
• Adobe Illustrator

So the first thing we're gonna do is get a picture of the katana we want to make. I'm going to use Illustrator so I can edit my reference picture to plan what I'm going to do. For my reference I will be using "Faith" from Nier Automata so I searched up a good, high quality picture and exported it to Adobe Illustrator. Next I started labeling what parts I'm going to make and added some rough measurements on the size of the katana. These are rough dimensions and might change when you finish due to tolerances or unforeseen errors. All units will be in inches.

The katana will split up into 3 different parts:

• Handle
• Handguard
• Blade

We are using a dowel down the middle is because we need it for structural support. The dowel I used is 7/16 in. diameter by 48 in. tall but I used dowel cutters to cut it down to 40 in. tall since it was better suited for the size I want the katana to be.

Lets start with the handguard since its the easiest parts to CAD out of the 3 parts we're making.

First, we're going to sketch out the shape of the handguard. Afterward, I duplicated the sketch, creating one slot for the blade on one sketch then the other sketch for the handle slot.

We are printing in 2 different pieces to avoid overhang. If we leave this as one piece we would have to add supports and potentially make assembly more difficult. Another reason is that the designs on the handguard will print out better and look smoother compared to being printed out in one piece. Next we will extrude the sketches for the top border. I used an offset path with a circle of approximately 0.1 in diameter then used the sweep tool so it can wrap around the top.

• Handguard Height: 1.34 in.
• Top border offset 0.1in.

(Optional) If you want to make the gluing process easier, add slots for your hot glue! This will make assembling easier for you. I didn't do it for this sword since I didn't think it was necessary.

The last thing for this step is to create a hole through the middle of both pieces for the dowel to slide through.

The next thing we will be making is the handle. Some swords will have an oval rather than a circle handle so its up to you which one you want to do, but in this case I'm using an oval since it fits the original design better. My katana has some designs on the handle so I added them accordingly; you can use these if you wish to or create your own designs.

Handle Dimensions:

• Ellipse 1.486 in. wide 1.732 in. tall
• Outer Ellipse 0.197 in. offset
• Outer Ellipse height 1.73 in.
• Handle height 12.5 in.

Make sure to extrude the center hole for the dowel and add a couple mm of height at the end to add some wiggle room for your dowel. This is will make it easier to assemble everything and give some room for error when your parts print out.

Katana blades are thin in real life, but keep in mind that you're going to need enough space for your dowel and you must still keep the blade sturdy. Also the katana I'm trying to make has these half circles on the side of the blade, but you can use which ever design you wish for your sword.

Blade Dimensions:

• Dowel Hole Diameter: 0.463 in.
• Width: 2.238 in.
• Length: 0.787 in.
• Height: 29.15 in.

The blade is extruded from the shape shown in the picture then cut at the end to create the tip. Afterward you're going to fillet the tip by 6 mm on the sides shown in the blue highlighted parts on the last picture to create the point on the end of the katana.

Once I finished CADing all my pieces on Fusion, I used Prusa Slicer and the Prusa Mini to print out the blade as shown.

For the handguard and handle pieces I used CURA Slicer and a Lulzbot Mini+. The prints will not require supports unless your designs have their own overhang.

For the blade I used 20% infill on 0.15 Quality. Print time: 20hr 51mins

I used 2 printers for the Handle and Handguard since I couldn't fit all the pieces into one build plate.

Handle and Handguard 25% Infill on Highspeed. Print time: 8hrs 4mins + 2hrs 3mins

Once we start printing everything, we can let the printers do their job and relax a little bit while we wait for pieces to print.

Break time is over, you're on the final stretch! Get your pieces off the printers and lets start assembling!

I started with putting the dowel into the tip of the blade then hot gluing each piece on top of each other. Use a flat surface to line up your pieces so they can glue together nicely. Afterward, I assembled everything I used black and white acrylic paint (brand doesn't matter use whichever one you like) to paint the curves on the blade and the diamonds on the handle.

Once you finish letting the glue and paint dry you are finished!

Congratulations on creating your own 3D Printed Katana!!

Now, you can use it for whatever you desire whether its for cosplay or showing it off to your friends! I hope that this guide was helpful in making your own 3D printed Katana and inspires you to create other cool projects like this. If you need help looking for new project I recommend searching "Berbawy" in the search bar, or go to her website, where you can check out other amazing projects you can create yourself!