Harry Potter Quidditch Trunk Replica

[skeplin]

Hello friends!

Many months ago I received a request from a friend of a friend to build a replica of a Quidditch Trunk from Harry Potter. After doing some research and taking some stills from the movie, I found a stellar post by Monkey540 with progress and plans. This thread highlights my progress and lessons learned along the way. I'll start with the finished shots -- I'm quite pleased with the result.

First things first, I worked from these movie stills. I used Adam Savage's technique of scaling to estimate the size of the box according to the characters as they appeared on screen.

With sizes in mind, I turned to Monkey540's plans and started selecting materials. I decided to use pine as it's easier to work with and has a more "worn" look to it when stained and sanded. I had a friend 3D print a full sized quaffle (in one go on his super-sized printer) so I could test the layout. One thing to note is I'm pretty sure they propped up the quaffle in that open-lid shot. There's no way it would have find in there with the lid closed the way it's presented..

With the sizes right, I set to gluing the base together and setting in the supports for the "shelf".

More to come as I organize my pictures!

 

[kavjapan]

Nice work! The quidditch truck is always such a cool project. I look forward to seeing the rest of the pics!

 

[skeplin]

The top of the trunk was challenging as I had never made a solid wood top before. Thanks to the plans provided I set my table saw to 87.5 degrees and cut the pieces for the lid. Like Monkey540, I made a jig to hold the lid pieces together while they glued. Band clamps are a must though I had to resort to ratchet straps to hold everything together equally.

I used a random orbit sander with 80 grit sandpaper to smooth the top and eliminate some of the ridges from the wood strips. To attach the curved section to the rest of the lid, I used wood glue and clamps with minimal brad nails to help where necessary.

Note that the curved section hung over the edges on each side by about 3/4". Once the glue dried, I ran painters tape down the side where I thought the edge started. I set an angle on my jigsaw to match the lid angle while keeping the blade at 90 degrees and carefully ran along the tape trying hard to avoid cutting into the side pieces. The great thing about pine is that it's easy to sand so it only had to be close enough.

I used threaded inserts in each of the "shelf" supports to hold the lid down with M5 bolts. This came in handy later...

{more to come}

 

[Monkey540]

Hello there skeplin , I am very glad that my thread and the resources in it helped you along your build. I think the end product looks great well done.
I will undoubtedly have questions as you detail your progress, but I have a couple for you to start.

Firstly, what did you end up doing for the handles. I found the original hardware that I used in my build were super uncomfortable for carrying the trunk so I recently redid them with a much more accurate design.

I'm also curious how you found the positioning of the support for the "shelf" level as you have supported from the bottom, and mine was dowelled into the sides. I found this gave me a good clearance for the lock mechanism, but I'm curious how it was in your build.

One more for now, how did you find the jig shape? I watched a you tube video where they did this for a curved lid, and the center "beam" I found really useful to tension the straps. If I had ratchet straps that would definitely have been the way to do it for me, but I had to manually try to tighten them.


I look forward to the rest of the build. Once again, very well done.

 

[skeplin]

Hello there skeplin , I am very glad that my thread and the resources in it helped you along your build. I think the end product looks great well done.
I will undoubtedly have questions as you detail your progress, but I have a couple for you to start.

Firstly, what did you end up doing for the handles. I found the original hardware that I used in my build were super uncomfortable for carrying the trunk so I recently redid them with a much more accurate design.

I'm also curious how you found the positioning of the support for the "shelf" level as you have supported from the bottom, and mine was dowelled into the sides. I found this gave me a good clearance for the lock mechanism, but I'm curious how it was in your build.

One more for now, how did you find the jig shape? I watched a you tube video where they did this for a curved lid, and the center "beam" I found really useful to tension the straps. If I had ratchet straps that would definitely have been the way to do it for me, but I had to manually try to tighten them.


I look forward to the rest of the build. Once again, very well done.

For the handles, I used off-the-shelf hardware from a big box store. I didn't like the color so I spray painted them with a textured black and then painted them with a "dark rust" color.

The positioning of the shelf was tricky. I used the movie still as a reference to determine how far up I needed, made a cardboard mockup, and used the 3D printed quaffle to eyeball it. Once I had that height down, I cut them out and glued them in place. The threaded inserts worked great as they allowed me to remove the shelf for painting and other work in the bottom (including the lock mechanism.) More on that later.

The jig shape was largely accidental. Your angel measurements and templates worked great so I printed out a paper template of the lid "sides" and used that to cut out the curved sections of the jig. Gluing was precarious -- I thought the whole thing was going to collapse on me a couple of times but I got it to hold. Making it oversized definitely help with positioning and getting the sides smooth.

 

[skeplin]

Part 3.

With the main box and lid complete, I set the hinges in place to ensure that it opened and closed as expected. I did have to sand the sides a bit to get things to line up perfectly. Typically when making a box you build it closed and cut the lid open but that wasn't an option in this case. I used off-the-shelf hinges because I liked the way they looked and used the shape to interlock with the metal "bands later in the build. Before I laid down a dark walnut stain for the base coat, I used wood putty on any gaps and sanded everything from 80 to 120 to 320 grit.

I used my X-Carve CNC to cut the holes for the "shelf". I was going to do it by hand but thought...no...it'll never be straight. Setting up the job was easy but I forgot I had modified the depth of the box a little and had to cut everything twice. Note that you don't need fancy tools to do this. A steady hand and a jig saw can get it done. I'm just picky.

The lid support was a really pain. I tried to use it as is -- it came with a hinged piece that was supposed to connect to the lid but the curved shape was given me fits. I ended up drilling out the pivot and used the hole for a screw. This took entirely too long and much trial and error to get it right without hitting the shelf. The support arm folds forward...it was the only way to get it to work right and the other way just seemed wrong.

I had friends help with the larger 3D printed parts (thanks Russ and Mike!) I printed a snitch on my Elegoo Mars 2 resin printer. I liked the ridged texture on the doors of the snitch compartment, they almost looked like wood grain.

I was making good progress and zipping along. Little did I know that I was in for the most challenging part of all: painting.

 

[kavjapan]

So jealous of your CNC!
Looks great. Keep posting

 

[skeplin]

Part 4.

Before I get to the painting, I want to mention another challenging part: organization. This project has a lot of interdependent sections and sub sections so I found myself constantly going to start something and realizing that I had something else to do first. With that, my daughter's wedding in May, and the deadline looming -- I turned to Agile/Scrum to help.

Each task was given a difficulty ranking using Fibonacci sequenced numbers between 1 and 13. That way, at a glance, I could see how difficult the task was. Additionally, I added tags to indicate whether the task was ready, in progress, blocked, or complete. I had a couple of decisions to make so I added a tag for that too. This method of organization helped tremendously and work efficiently.

Now on to the next task: metal straps. I decided to use aluminum flat bar for the trunk straps. I doesn't require any heating in the forge and is easy to bend into shape. I used a vice and a 3 pound hammer to gently coax it into shape, checking it against the curve of the lid until I was happy with the shape.

I decided to add a lock and key to the trunk and carefully routed a pocket in the front for the mechanism. Later, I realized that I made the pocket a bit bigger then necessary so I had to go back later and add a wood piece for filler. I cut the tongue of the catch with my portaband and filed it into shape, trying to match the reference picture as closely as possible. I then riveted a small hinge onto the flat bar and attached it to the middle strap. For the lock "catch", I bent a nail into a square shape and fed it through two small holes I drilled into the tongue. With a hammer, I carefully peened it over so it was locked into place.

Ok now for the hard part: paint.

 

[skeplin]

Paint.

I didn't realize, or perhaps underestimated, the amount of work involved in painting the trunk. For the inside, I mixed a super dark green acrylic color and applied a couple of coats. The mixture was probably 80% black and 20% forest green. Maybe 90% black. It looked super dark when it went on but in the light really showed the green tint. I then painted the edge pattern using dark brown acrylic for the base coat and hand-painted all of the "triangles" to more closely match the homemade look in the movie stills.

The paint looked OK, but was too crisp and new looking. This was a box handed down from generation to generation, perhaps hand-painted by the original Gryffindors team. To weather the paint job, I took 320 grit sand paper and rubbed off as much paint as possible. After that, it started to look more real.

To paint the metal pieces (including the top straps) I used acrylic spray paint -- specifically Rustoleum hammered black. This added a rough texture which coupled with Vallejo dark rust made for a convincing worn/rusted metal effect.

For the front and top tartan pattern, I made an actual size pattern in Inkscape, printed to size, and then cut it out by hand. This was time consuming but it was the only way I could think of to accurately transfer the pattern to the box. After carefully tracing it with pencil, I think laid in the brown base color and added the details.

Next up: More paint!

 

[kavjapan]

I always loathe the painting step in projects (mostly because I'm not very good at it).
But weathering and aging it afterwards is so much fun when it really starts looking good.

This trunk is gonna be awesome.
Look forward to more pics!

 

[Monkey540]

Painting was definitely the most time consuming part of the project for me. I ended up putting about 3 coats of brown, and 2 -3 coats of the lighter colors just to get a nice even consistency.

I really like the work you did on the latch piece. That's one piece of my build that haunts me.

How did you find the prints for the bludger rings? Those were interesting pieces, but I personally had a tricky time with gluing the holds and latch in place cause the points of contact were so small.

I look forward to seeing the next part of your build.

 

[skeplin]

Monkey540 Your STLs were spot on for the build -- thank you so much for sharing. The only trouble I had was with the bludger "caps" where the hooks glue on. I knocked a those off a couple of times trying to get the chain attached corrected.

 

[skeplin]

MORE PAINT!

With the outside of the trunk well under way, I turned my attention to the inside. I cut a piece of quarter inch luan to fit the inside of the lid and traced the outside of the snitch holder onto the center. I then cut it out with a jig saw and remembered that I could have more easily just cut it on the laser. DOH. Instead, I used the laser to burn a light outline of the "tree" pattern. I also ran a cardstock template for the house mascots to be painted on the front and top.

I decided to cut the inside crests out of 1/8" MDF and used the same light engraving technique to give me reference for painting. Like everything else, I decided to paint these by hand and was quite happy with the result. I also went back and added additional shading and depth to the "tree" to give it a more painterly look.

I glued down all of the crests, pressure fit the snitch holder, and screwed the luan piece into the lid. I used the same green paint to help to hide the screws. To weather all of the "metal" parts, I first laid down a coat of gunmetal grey acrylic paint, followed by dark rust, followed by rust wash, and finally topped with a black wash and wipe. I purchased some black decorative chain from the big box store.

Note: I attempted to forge some metal corner guards out of 3/8" mild steel but wasn't able to get the consistency right. It's difficult to get the shape right and then bend all of the pieces. With 12 in total, I decided to resin print them and epoxy them into place. I did however manage to turn out some pretty nice metal wands. I twisted them in the vice and did some manual file work with chainsaw files to create a thorn pattern.

With all of the pieces complete, it was time to start buttoning everything up. But one more stretch goal...

...animatronics. (sort of)

 

[kavjapan]

Fantastic work!