Introduction: Pete's Dragon Lighthouse Prop

My wife and I like to have a theme for our families Halloween costumes. This year my wife came up with the creative idea to do a Pete's Dragon theme. My toddler daughter will be Elliot the Dragon, I will be Dr. Terminus, and my wife will be Nora the Lighthouse keeper. While my wife set to work sewing the Dragon Costume and making my outfit, I was tasked with making a stand-out costume for her to be Nora.

How does one make an eye-catching costume for Nora, when she was a pretty regular character, in fact the only regular looking character in the movie. Well you make a 3-d printed, light-up Lighthouse model prop, complete with rotating lens and extra night-light inside. My original plan was to make the base big enough that it would double as a trick or trick bag for collecting yummy Halloween loot, but due to the size I wasn't able to 3-d print it that big, and it probably would have been too big and cumbersome for her to carry anyway.

Thanks to the awesome staff at the Boise State University Library, I am now the proud owner of a 3-d printed Lighthouse model.

Follow the steps below to see the lighthouse take shape. I made the drawings in TinkerCad. This was my first attempt at using TinkerCAD but I found it very easy to use once you get the hang of it.

Step 1: Materials and Tools

First off you need access to a 3-d printer or 3-d printing service. I will include the drawings I made in a later step.

After completing the drawings and printing the lighthouse you will need several things to make it go from a cool looking piece of plastic to an eye-catching costume prop.

Links provided are for Items similar to the Items I used and may be found for a cheaper price or from a better seller, these are just examples. Really you can use anything you have on hand most all of these could be swapped out for other items altogether and work just as well.

1 - 12v Slow Speed Motor

1 - Motor Speed Controller

1 - Harbour Lights - Fresnel Lens Christmas Ornament- HL 716 5th Order

1 - Yellow LED Light and Resisters

1 - 1156 LED bulb, 18 5050 SMD LEDs1 1156 LED bulb, 18 5050 SMD LEDs

1 - 1156 base socket (I went to a vehicle junk yard and got 3 of them for $2)

1 - 8 AA Battery Holder

3 - Push Button Switches

Small Gauge Electrical Wire

Stiff Wire for Handle

Floral Wire For connecting the Lens Ornament to the Motor Shaft

Screws

Velcro

Small Bungee Cord

Gorilla Super Glue

Tools:

3-d Printer

Drill and Various sizes of Drill Bits

Wire Strippers

Wire Cutters

Pliers

Knife

Screw Driver

Soldering Iron

Optional: Voltage meter

Step 2: 3-D Printed Parts

I tried to make a fairly close replica of the Lighthouse used in the movie, but since this is my first 3-d printed item and I only had one chance to print each part, I am missing some details from the original Lighthouse, which interestingly was built just for filming the movie and then dismantled after filming was completed.

I designed the Lighthouse to be 12 separate parts in 10 drawings; that I would assemble together after printing. I glued most of the parts together but wanted to be able to have access to the Light bulbs, motor, and batteries later. I tried to incorporate this into the design.

BEWARE: I have not altered the drawings since I had it printed. There are some issues in the drawings that make the parts not fit together quite as designed.

The tabs on the Top Base that are meant to slide down inside of the middle part and then get held in by the locking keys don't fit.

Also the very bottom base piece isn't as big as the bottom of the base, but also not small enough to fit up inside.

The locking keys stick out too far as well, since the motor is a bit off center.

You may also run into some other issues depending on what you scale the drawing to and the tolerances of the printer you are using.

My printed version ended up being scaled down to about 50% of the drawing dimensions.

Here are the individual parts and drawings:

Part 1: The Base door and candy slot door

As mentioned above this piece has a size issue. It isn't as large as the bottom of the first base piece, but it also isn't small enough to fit up inside the base either. If I were to do it again, I would make this piece thicker and make it as large as the outside dimensions of the base so that I could countersink some screws into it and attach it that way. I ended up using an non-elegant Velcro method.

This drawing also contains a small part that can be used to plug the candy slot mentioned in part 3 below.

The Video Lighthouse Base Door, shows the base door and candy slot door printing.

Part 2: Base Piece 1

There are no issues with this piece it is a simple Hexagon with slanting sides.

The Video Lighthouse Base 1 shows Base Piece 1 printing.

Part 3: Base Piece 2

This glues on top of Base piece 1 and tapers even further. It also contains a window just for aesthetics and a hole in the upper back part that can be used as a candy slot if done at full scale, or in my case to access the inner night-light.

The Video Lighthouse Base 2 shows Base Piece 2 printing.

Part 4: Middle Piece 1

There really isn't anything special about this part.

The Video Lighthouse Middle Part 2 shows Middle Piece 1, Middle Piece 2, and the Locking Keys printing.

Part 5: Middle Piece 2

There also really isn't anything special about this part.

The Video "Lighthouse Middle Part 1" shows Middle Piece 2 and the Top Base being printed.

Part 6: Middle Piece 3

This was originally designed with a shelf inside it to support the battery pack, with my scaled down version I had to cut off the vertical part of the shelf so the motor would fit. I ten used the horizontal part of the shelf to hang the night-light from.

I glued these 3 middle pieces together before gluing them onto Base Piece 2.

Part 7: Top Base

This is the one I mentioned above that the tabs are not drawn correctly for it to line up with the slots in the top of Middle Piece 3, I ended up cutting the tabs off altogether. I drilled a hole through the little square blocks and into the side of Middle Piece 3, 90 degrees from the slots in Middle Piece 3. I then used some stiff wire to make a carry handle and inserted it trough these blocks and holes, the handle now keeps the top attached to the base rather than the locking keys. You will make a small hole in this for the motor shaft to pass through.

Part 8: Locking Keys

These were designed to hold the top one while providing access to the motor. I didn't end up using them. I think they need some adjustments in the drawing to fit right.

Part 9: Top 1

This is the lens housing, I made a hole in the bottom of this large enough for my Lens Ornament to pass through. This part is attached to the Top Base with the motor screws and a piece of tape between the two pieces. I also made a small hole near the edge for the wires to pass through that power the LED.

The Video Lighthouse Top shows the Top 1 and Top 2 printing.

Part 10: Top 2

This is the roof and last piece. I ended up hollowing out the inside center part because my lens is a bit higher than the cage, this allows the wires and LED light to be hidden inside the ceiling. This has holes that line up with the cage posts from Top 1, but they may need to be opened up a bit with a knife. Glue this part to Top 1.

Step 3: Assembly

Now that you have all the parts printed. It is time to make everything fit. I started with attaching the motor to the underside of the Top Base, Depending on your motor you want to make it so that the shaft will come through as near the very center of the circle as possible, while still being able to fit inside of the Middle 3 piece. Mine ended up being slightly off center, but not by much. Once you know where the shaft will be you can make a hole in the Top 1 Piece. This should be large enough for the lens to fit through. After that Hollow out the Top 2 Piece for the light and wires to fit into the roof.

Now drill holes through the side of Base 1 to insert the switches.

You can now start doing the wiring following the attached circuit diagram. I wanted to be able to control each of the 3 things separately, so that you can have the Lens light on, the motor turning, and the night-light on, in any combination you want. It seems complicated when first looking at the drawing, but it really is 3 simple circuits.

After doing all the wiring, put a screw on the inside of the Base 1 piece near the top and attach a small bungee cord to it. You can then insert a screw below it near the bottom to attach the other end. This will hold the battery pack in place.

Now that everything is in place and working properly, you can glue the pieces together following the gluing tips in the explanation for each part above.

After everything is glued and dried you can attach the base door. As I said I used Velcro, but it would be much better to use screws.

Step 4: Final

You made it! Now you can sit back and admire your handiwork and make everyone at the Halloween party jealous. That they don't have a costume prop as cool as yours!

As you can see it isn't exact to the original, but i am happy with the way it turned out.