I love my headphones, which is good, because I wear them like 10 hours a day. On my old chair, I would just hang my headphones over the back because the back of the chair was about as thick as my head. Recently, I got a new JÄRVFJÄLLET office chair from Ikea. The chair is nice and sleek, but it didn’t have a good place for me to hang my headphones when I’m not at my desk. So obviously I just designed one in Onshape and 3D printed it.
The chair has a single pipe with a rounded rectangle cross section holding up the back. The end of the pipe was capped off with a rubber plug. This was a great place to do the integration, because the pipe has a very simple geometry. I just modeled the end of the pipe, then modeled a hook, and put them together to get the general shape. I did one design that was too short, causing the headphones to fall off when the chair was quickly reclined. This is the version 2.
This design is split into 2 pieces because one piece needs to be printed to optimize strength and the other needs to be printed to optimize appearance.
The strength of 3D printed parts is orthotropic, which is a kind of anisotropy and is a fancy way of saying that the part is stronger in one direction than in another. 3D printed parts are particularly weak to separation of the layers, so printing it in an orientation where the tensile force vectors and layer planes are parallel improves the strength because there is no force that could pull the layers apart. That is why I always try to design pegboard parts to print on their side. Like for pegboard, this is also a hook, so printing it lying on its side means the weight of the headphones on the hook part is co-planar with the layers. The second part, the little cap, is mostly aesthetic. Printing it upside-down means that the top surface will be nice and smooth, matching the texture of the 3D printer’s build plate. By separating these, both parts can be optimized for their purpose and both can be printed without supports.
This hook is working really well. I like that I can hang it on my chair and have the headphones available to me when my desk is closed in the closet.
You can grab the STL files on Thangs here or you can fork my Onshape project here.