This is an awesome tutorial on how you can use SOLIDWORKS and 3D printing to create your own inspired replica sword with lights. The sword in this tutorial is inspired by Genji from the latest multiplayer game Overwatch. I will show some new tricks and techniques I use to create a replica like this one. For some basics of designing for 3D printing check out our previous tutorial!
The main focus of this tutorial is designing for existing, store bought components such as the battery box and the LED strip we purchased online. We’ll take a look at how to use tolerancing while designing for interference fits and moving parts, as well as using your print setting on your slicing software to benefit what you are doing. You should use this tutorial as a guide to help you create your own replica props.
I modelled the sword using basic SOLIDWORKS features and surfaces. I used one dimension to determine the length and the rest of the shapes were created to a scale according to the height, to make it look good and proportional. The problem with this is you can easily lose perspective and idea of the printed scale. To combat this, we can cut a small section and test print to make sure we’re on the right track. In this case, the original model turned out huge, so we changed the scale to a better suited size. The image below shows the old scale (on the left) compared to the new scale (on the right).
Half way through the build, we made a visual representation of the actual battery box and toleranced the model around this. This helped us understand the scale, and allowed us to build the model around the battery box to ensure a proper fit.
When it comes to creating a tolerance for the parts, each machine is different. The best advice we can give in this is to test your machines accuracy. Print a boss and a hole with a variety of different tolerances. This will allow you to create a basic scale which you can use in the future. With this model, I used a tolerance of 0.3mm for the tighter fits, such as the blade fitting tightly into the hilt. For the loose fitting and moving parts such as the switch and the battery box, I doubled that tolerance to account for easier fitting and movement.
Once you have completed the model the next thing to do is cut it up into manageable pieces which your printer can handle; this is where your print bed parameters come into play. Save each part as an .STL (this is the format 3D printing slicing software can understand). You will then import your .STLs into your slicing software, orientate them, and prepare them for printing. For a more in-depth discussion on this process, check out our previous tutorial. In this case, we’re going to focus our discussion on the infill options for our sword.
Infill is the density in which the internal material is filled; most of the time we use 15%. This means 15% of the internal mass is filled with plastic while the remaining 85% is just air. The slicing software calculates this for you, so all you need to do is input the percentage desired. The higher the infill percentage, the more plastic you use, and the longer the print time will be. Below is an image illustrating what infill looks like as the machine prints. It creates a crosshatch pattern to ensure structural integrity.
To achieve the defused light look on the blade we used what’s called Natural PLA or Clear PLA material. As each layer defuses the light, the model becomes less and less clear, making it opaque, kind of like scratches on the glass. This works well to create a light diffuser. If you use a lower infill, this pattern can be seen and more when the light is on. If you wanted to, you could manipulate your infill to create pattern, but in this case, all we need is a basic diffuser. This means we have to print these parts at 100% infill, keeping the shading even and allowing the light to be defused well. This can increase your print time and material use, but since our sword is so thin, the overall project isn’t affected significantly.
Once the parts are printed, you will need to clean and glue them all together. To clean off any support material, use pliers to break it off and a knife to cut off any extra pieces. Use the knife to clear up any excess material on the surfaces that need to be smooth. When it comes to gluing, super glue does just fine with these props, especially for the size I have made mine. With larger replicas, an epoxy resin will be better as it crystallises harder than super glue.
We stopped assembling half way so paint could be applied to the model. This was done to keep paint off of our clear parts. We don’t want painting mishaps to affect the look we are trying to achieve. Any paints can be used, but a simple water based acrylic was enough to apply a black coat and some silver highlights here and there.
Once the paint job is done, we wired in the LED. This was simply threaded through and stuck down. Then, the light defused blade part was glued into place. Finally, the rest of the blade was assembled. The pins I created initially were not strong enough, so a simple fix was needed. You could update your design and reprint, but in many cases, a do-it-yourself solution can be much easier. I drove to huge nails in the body and sealed it with a screw, saving quite a lot of time and material.
Once you have completed the model, you are now officially more awesome and ready to turn heads with your amazing prop making skills at your next local comic con. This simple tutorial can be used to guide you and help improve any work you have begun, or help you get started with your next awesome cosplay using the power of SOLIDWORKS and 3D printing together! See you for the next one!