A cosplay prop, made with a combination of 3D printing and old-school electronics
During ExpOtaku 2016, cosplayer Kokoro Love used the key during her performance as Serena.
Last week, a friend expressed her desire to participate in a national cosplay contest. She would be interpreting Serena, the female protagonist of the Pokémon XY anime. To be more specific, she will be wearing the attire that Serena uses during a Pokémon Performance events... And an important part of this attire is a key with a heart-shaped jewel that shines.
I decided that this prop would be an interesting thing to make, so I started working on it during my spare time! The first step was to gather enough reference pictures to get an accurate idea of the key's shape and dimensions. Unfortunately, this is an item that didn't show up in a simple Google search. So, I had to identify an episode where the key is featured prominently (thanks to Bulbapedia, this was an easy task), download it and take screenshots that I could use as reference.
During the process, I learned that there were inconsistencies in the key's design, so I decided to draw a sketch that would be an "average" of all the divergent features and use it as my reference to do the 3D model.
After that, I opened SolidWorks and started working. Using Serena's height and the key's relative size to hers, I estimated that it should be 18cm tall. So, with that in mind, I made the first two models: One for the key's body and other for the heart-shaped jewel.
In order to print this model successfully, I further divided the key's body into two halves that were later glued together.
After receiving the thumbs up from my friend, I decided that it was time for the second step: Making a circuit that would provide the lighting effect.
This circuit needed to be reliable, simple, and most important: Small. I had about 3cm3 to put the battery (which had to be replaceable) and all the internal components. Because of this, I decided to choose the old but reliable NE555.
After I got satisfied with the fading effect, I assembled the final circuit using a couple of very small PCBs cut with the help of a dremel.
And now, I had to update my design in order to make room for the electronic components. I'm glad that everything fit at the first attempt, so there wasn't any need to make several prototypes.
The next step involved a lot of sanding. I wanted this item to have a smooth and nice appearance, so I spent a lot of time carefully sanding all the surfaces to erase any imperfections.
I'm glad that cuticles grow back... I ended up having an accident while sanding.
Afterwards, I applied XTC-3D to all the pieces to give it a shiny, smooth appearance. Actually, it was my first time using it... and I should say that it was a good experience, except for the smell.
After the XTC-3D finished curing, I put the electronics inside. It was a perfect fit!
And after a week of work, the item was finished!