Rey's Lightsaber From "The Rise of Skywalker" - 3D Printing and Design

This build is my first successful attempt at creating a replica of a film prop. This is a replica of the new, yellow-bladed light-saber seen at the very end of "Star Wars: Rise of Skywalker". It had very limited screen time so I did not have much reference material to work with and thus this inspired a design element that I have not used before: threads. Nearly every component of this build has threading so that everything can be assembled without glue and thus is much easier to make changes to if additional reference is released or I have the desire to modify anything.

I had the goal of completing this entire build for the 3d printing contest, however I ran into some time constraints that did not allow me to do so. This being said, I decided to make this instructable more along the lines of a design guide to show my processes of trial and error along with the things that I learned along the way. I still plan to complete the painting, weathering, and overall finalizing, however that will be released in a later instructable.

This design was made completely in Fusion 360, the gcode was sliced in Cura, and printed on a Monoprice 3d printer

These following steps will show how I designed this light-saber as well as the simple assembly for this build.

Step 1: Materials

• 3D Printer (or online 3D printing service)
• 1 spring - the size used can be found in pens (I got one from a Tul pen)
• 2 M2.5 machine screws
• A small screwdriver
• 3D printing post processing tools
  • Needle-nose pliers
  • Small file (ex. from a multi-tool)

Step 2: Design

These following few steps will show you both my thinking surrounding this project along with how I used Fusion 360 to design it.

Step 3: Hinges

When I first saw this light-saber in the movie, I found the coolest part to be the activation mechanism. When the dial is spun, flaps open up along the top of the saber right before the blade comes out. This is a component that I definitely wanted to include in my design.

These flaps on the top of the saber could be done in many ways, however I wanted to attempt to make this top piece printable all in one component rather than leaving it to assembly after the fact. For this to work I employed a method of a print-in-place design.

As seen in the pictures above, If there is enough room between the bar and moving object, the object will be able to move right after being printed.

Note: Make sure to print this part without supports as they would impede the movement of the flaps.

Step 4: Top Mechanism

To achieve a similar effect to the light-saber in the movie I needed to transform circular motion around the light-saber to perpendicular motion directed out through the top of it. This took a bit of brainstorming and trial and error, however I believe that it turned out pretty well in the end using a non-conventional mechanical design.

Design: To make this work I essentially used a wedge on the dial that pushed up on another part. This second part runs along a track that both directs it's motion in a straight line and keeps it from spinning. Another problem that comes with this is that if tipped upside down, the moving inner part will slide along without the user spinning the activation dial. To remedy this I used a small spring from a ballpoint pen and was able to keep the sliding part from moving.

It is then fairly simple, though a bit time consuming to attach wire to to both the sliding component and the top flaps. This will allow the flaps to open up when the sliding part moves up and vise versa when it retracts.

Note: Step 8 contains assembly details for this part

Step 5: Threads

Using threads for this build allowed for much more flexibility. For one, I was able to print smaller pieces without the fear of a difficult assembly process that could take much longer. This also let me print pieces faster so if there was a failure or if I needed to reprint a piece, it wasn't much of a hassle. Secondly, there wasn't much reference material to lean on for this project so some of it was up to creative interpretation and other reference that may or may not have actually been correct. Using threads rather than other assembly techniques will allow me to edit and change out components in the future if there is any need to do so.

Tip: This was the first time that I have been able to make threads work with my printer and there are a few things that I learned along the way.

1. Fusion 360 threads are not going to work by default with a standard FDM (filament) printer. They simply print out way to tight and can not be feasibly fit together. After a few tests and research on forums I found that there is a very easy solution to this however. There is a tool in Fusion 360 called "offset face" (solid -> modify -> offset face) which can allow you to easily make the threads thinner. After using this method the threads work very nicely and I most definitely recommend using them in other designs as well.
2. Do not over tighten pieces with threads. When assembling pieces, make sure to only tighten them until they are snug and not like you could do with metal components or they will break.

Step 6: Handle

Yes, it is curved. Yes, that is intentional. No, that is not how it looks in the movie. :)

As mentioned previously, I am still planning on adding much to this, however this instructable is primarily for showing my design process.

Design: The handle is curved in order to allow room for wrapping the handle with fabric as was done in the film. This curving was simply done using a fillet, however one could also use a chamfer to get a similar result.

I will include a file for both a smooth and rounded handle.

Step 7: 3D Printing

These are the 3d files for this project. Please consider these two things:

1. Make sure to scale the files down by 50% (I will fix this shortly)
2. Try to not use supports for the components with threads as these would make it much more difficult for post processing. If you do need to use supports I was able to set the "support overhang angle" (in Cura) to 80 degrees and it didn't print on the threads which worked nicely.

Note: The files are now labeled in reference to the picture below.

Step 8: Assembly

These next steps will outline the basic assembly of the light-saber.

Note: Use the numbers in the picture above to help with assembly.

Step 9: Top Mechanism Assembly

1. To start off, cut 8 ~3 in. lengths of wire and feed them through the 8 holes located on the top of the small, soon to be, sliding component (#4).
2. Thread the small spring holder (#2) into the large top piece (#3) and place the spring inside the inset part (#2).
3. Gently feed the sliding component (#4) into the large piece (#3) so that the spring goes into it's inset hole. Make sure that this piece can slide and spring nicely inside the large component.
4. Thread on the next piece (#5) and insert the dial (#6) into it.
5. Place the final top component (#7) on top and screw it in using the two machine screws.
6. Flip the mechanism around so that the top is facing up. Thread on the top component (#1) so that the wires are going through it. Feed each of the wires into their corresponding flaps (#1) and trim the ends if necessary. Note: make sure that the sliding component (#4) is in it's furthermost upright position before feeding the wires into the flaps. Turn the dial (#6) clockwise to ensure this.

Step 10: Handle

1. Fit the two parts of the handle together.
2. Thread one side of the handle to the top mechanism. Note: It doesn't matter which side of the handle goes into either side of the saber as they have the same thread size.

Step 11: Bottom Half

The remainder of the light-saber is fairly self explanatory. Simply fit each component together in the correct order as seen in the reference above using the numbers in the picture on step 8.