If you plan to live long and prosper, it's good practice to protect your ears in loud environments. In this tribute to Leonard Nimoy I customized earmuffs with the famous Mr. Spock ears.
Step 1: Step 1: Document and Measure
I modeled after this particular set. It might work with other 3M Peltors too.
The earmuffs are easy to take apart. They consist of a headband, 2 cups with ear cushions and foam liners. Pull on the ear cushions to take them apart.
Caliper in hand I started measuring all parts.
First up was the outline of the cup. The curvature is important for a good fit so I traced the outline with a pen and added details.
Next step was getting an idea how the ear cushion snaps into the cup. It's hard to measure inside the cup so my colleague Joshua was suggesting using Play Doh. I tried that as you can see in the pictures but in the end we learned the easiest way is to measure the outline of the cushion.
I measured the handles for the headband and the insets for airflow while modeling.
Step 2: Model Cup in Autodesk Fusion 360
I intended to learn Fusion 360 for a while and this was the perfect project to get started. It took me a few days before I was comfortable in the software because it's nothing like the sub-d modeling tools I was used to but I'm glad I took the time. For a CAD program with these abilities it's actually an easy learning curve.
I tend to learn new software by watching other people so the YouTube channel of Fusion 360 was a great start and Andreas at Pier 9 was kind enough to answer some of my initial questions.
Check out the video to see the steps involved.
Step 3: Test Prototype
Prints are expensive so I printed the bottom part to see if I got a good fit to the cushion. My first printed prototype didn't fit because of a wrong measurement on my behalf. The next iteration was spot on. Making the measurement change is very easy with Fusion 360, which is one of the reason I'm growing fond of it.
I'm lucky to have access to an Objet Printer, but I'm planning to do some tests on consumer grade printers as well.
Step 4: Model the Ear
I modeled the ear in Modo based on the standard human ear from the presets and a reference picture from Mr. Spock that I found somewhere on the internet.
It took me a few hours of pushing and pulling vertices to arrive at a shape that I was happy with.
Step 5: Merge the Ear With the Cup
If you want to print this in 1 material it's best to merge the 2 models together.
The ear goes deep inside the cup so I exported the ear and imported it into Fusion 360. Based on that I cut out a part of the cup, which made it easier to merge the two.
If you don't have access software like Modo, I recommend using Meshmixer. It's free software that allows you you mix multiple models together and tweaking details.
My .stl files are attached. Feel free to do whatever you like with them.
Step 6: Print a Prototype
After the models were merged I printed another prototype. Viewing something on a screen only goes so far, holding in your hands gives you the full experience. Thanks to Shalom for the picture (and the one in the shop)
Step 7: Prototype 2 and Beyond
The Objet printer can print 2 materials at the same time, so for fun I wanted to see if I could have soft rubber ear on a hard shell cup, which is where I am right now. As you can see in the picture, it's not a deep black so I would have to spray paint it...
I'll be making the other ear in one of the coming days and I'll share the final results as well. In the mean time, don't hesitate to try it out yourself and let me know how it works for you in the comments.
Let's make Mr. Nimoy proud :)
Step 8: Prototype 3: Dremel PLA Print
Matt at the office helped me prepare a print on the Dremel 3D printer. We wanted to try out that glow in the dark PLA material anyway :)
The extrusions for the headband were messed up, but I could easily fix that by making it square instead of circular. What happened inside the ear is hard to tell, maybe something jammed. But it's nice to see that this is working on a consumer grade printer too.