I got inspired by a friend who told me about a serotonin molecule metal necklace. You can find some that cost between $7.50 and $70 on google shop, or from a company that specializes in jewelry inspired by chemical molecules.
This neurotransmitter molecule has many functionalities on the body, but the most popular is its relation with mood and happiness, so it is known as the happiness molecule.
You can read all about the interesting functions of this neurotransmitter on wikipedia.
Step 1: 3D Modeling Using Fusion 360
Fusion 360 seems like a pretty good solution for anyone who wants to start learning 3D parametric design, or freeform T-Spline modeling.
The software works on Mac and Windows, and is cloud-based, but can work offline too.
It takes care of version control, so collaborating with other users is very easy.
Step 2: Create a Project and a New Fusion Design
Once you open Fusion, there's a Create button in the dashboard, where you can start a new project and selectmembers who you want to collaborate with.
Then, create a new fusion design linked to the new project you've just created.
Step 3: Starting With a Sketch
There are many ways to start design your happiness necklace, you can start freely creating basic 3D shapes by clicking on the Create button, or by sketching 2D lines.
For creating a sketch, click on Sketch button, then Create Sketch, when prompted to select the plane, select the XZ plane.
Step 4: Importing a SVG File
Let's import the skeletal form of the molecule from the wikipedia article. It's the SVG file: Serotonin-2D-skeletal.svg
Click in Sketch button then import SVG.
You must select the start position for your sketch.
You'll notice that the letters from the SVG file don't look so nice. Just select them and delete.
Step 5: Before 3D
Before going to the 3D world, let's make some construction points that will be useful in the next steps.
First, create a line between the gap, click Sketch / Line then Sketch / Point and create three points that follow the image.
Then, use the Trim command to delete the remaining line segment you've just created.
Step 6: Suddenly 3D
After cleaning up all the vectors, let's start bringing it to the 3D world...
Using the Create Form button you can go to a free form environment, and using the Pipe function create complex topologies based on the sketch curves we just produced.
The Pipe function has many parameters, I recommend you play and discover the possibilites, or you can just set it up as the pictures above. I choose the squared ends on End Types.
After selecting all the parameters and the sketch lines, just click on Finish Form. It will produce a new 3D body.
Step 7: Adding the Sphere Atoms
Adding the atoms is super easy.
There are three points we added early, those will be our reference coordinate points. Using the basic 3D forms under Create you can create a sphere by just selecting the center point and giving it a diameter. As you create the body it will be joined, intersected, or cut with existing bodies, or you can chose to make a new body. I chose a new body so at the end we will have four different bodies.
Step 8: Going Back to 2D
This step will show how to produce a 2D sketch from our 3D model so you can cut it on a laser cutter or water jet.
First, create a component, rename it then move all the bodies into this component.
Create a new Sketch and select the XZ plane.
Now, inside the sketch environment you can use the tool Sketch Project Cut Edges to project all the edges of our 3D object inside our 2D sketch. You just need to click on each body, then click on Stop Sketch. You can hide the component so you will see only the 2D sketch.
Step 9: Exporting a DXF From Fusion 360
Currently, there's no easy way to export a vector file from Fusion, but it seems like the next release in May or June 2014 will include a way to just right-click on your sketch and export it as DXF.
But there is a tricky way to to that with the current version.
You'll need to create a new component and move your Sketch to there.
Then, right click over your component on the Browser and Save Copy As, this will create a new Design based only on this component.
Go back to your dashboard, click in Tools over your new Design them export as DXF. When for your DXF file to appear on your dashboard, and download it!
You can use Inkscape or another tool for vector editing, and add some finishing touches before cutting it.
Step 10: Files for Cutting
Here are the source files