3D Printed Functional NASA Penlight

I am currently working on an Apollo 11 spacesuit, and when I discovered that the shoulder had a specific pocket for a penlight I knew I had to make my own!

Commercial replicas of the penlights made from brass are available, but are quite expensive. As this is a costume prop I just wanted a reasonably accurate replica to store in the spacesuit's pocket, not something to carry around all the time. I did however want it to be a working flashlight, so I found a keychain flashlight to place inside.

A note on the model's accuracy:

I have made efforts to make the model accurate, but I have made some adjustments to fit the flashlight and avoid overhangs when 3D printing. The engraving is the same as on Buzz Aldrin's Apollo 11 penlight.

You will need access to a 3D printer, a Ledlenser K2 flashlight, a bit of masking tape and some paint. If you want to improve the surface of your model before painting, you will need some sandpaper and filler.

I printed the model with black PLA filament, sanded the model with sandpaper and a Dremel rotary tool and painted the model with a base of some locally available gold acrylic paint and then a couple of layers of Vallejo Liquid Gold (Old Gold).

Download the files here: https://www.thingiverse.com/thing:4705633

The model consists of two files, the upper and lower body. The models should not require any supports when printing. You may want to use a raft for the longer half to avoid it coming loose during the print, as its bed footprint is quite small.

My model was printed with 5% infill and 0.10 mm layer height with black PLA.

Remove the raft (if used) from the parts. Metallic paint is very unforgiving when it comes to uneven surfaces, so I sanded the model and used some filler to smoothen out the layer lines and other imperfections. Be careful when sanding around the debossed letters to avoid sanding away the finer details.

I wanted a black base for my paint, so the spots where I used filler were covered with black acrylic paint before the next step.

Paint the model with your choice of paint. I used a locally available gold acrylic paint and finished off with some Vallejo Liquid Gold metallic paint for a more realistic finish.

Optional: Put a bit of gold paint on the edge of the flashlight to make it blend in with the model.

To make the engraving and knurling really pop, you can weather the model with some thinned down black acrylic paint.

Now comes the slightly tricky part:

To make the penlight work, we need to make the bottom part of the flashligt turn when we turn the body of the penlight. To keep the upper part still, I added a bit of masking tape to the head.

1. Assemble the completed model. Screw the head in as far as it will go. Then unscrew it by almost half a turn.

2. Add some masking tape on the head of the flashlight. I taped two complete rounds around the head.

3. Unscrew the bottom of the flashlight by about a quarter of a turn.

4. Find the recess in the penlight body and aim the flashlight accordingly.

5. Insert the flashligth completely into the penlight. If done correctly, the head of the flashligth will be flush with the edge of the penlight opening.

This part is a bit tricky to get right, but when done correctly you will be able to turn the flashlight on and off when twisting the body of the penlight.

I am certain this is not the easiest way to achieve this, but as this is just a costume prop I did not spend a lot of time to find a solution for the switch. If you have any suggestions on how to improve this I would love to hear from you!