Pop Up Middle Finger Box - Spring Loaded, Fully 3D Printed, No Supports, Easy Assembly

I wanted to address an issue many people have been having with a loss of spring tension over time.

Unfortunately, due to the properties of plastic (even PETG), if a spring is kept under tension (such as when the box lid is closed) for a long period of time it will deform and lose spring power.

To offset this, I recommend storing the box in the OPEN position to maximize its lifespan.

_________________________________________________________________________________________________________

Ever get tired of flipping the bird on your own? Well, this box is for you! Fully 3D printed with no extra parts needed, its easy to print and assemble. Simply press the lever and the lid and finger will flip up on their own, and shut the lid to rewind the spring to reset it.

I added the “Press Me” text through Prusaslicer's text modifier - feel free to add your own and customize it!

Printed on a 0.4 nozzle with 0.2 layer height, 15% infill. Remember you'll need two spur gears!

Please note that this model does require printer tolerances to be dialed in to allow for easy movement of the mechanism inside. I've included a test post file - print that along with an intermediate gear. It should need a bit of pressure to mount onto the post, then spin freely, but not fall back off. If it fits too tight, try reducing your flow/extrusion multiplier.

I highly recommend printing the main spring and latch in PETG, as PLA has a tendency to set after a while and lose spring power. Even so, plastic held under stress will deform over time - I recommend leaving the box open when not in use to extend the spring life.

If you feel like the middle finger isn't your speed, the mounting post is 3.5x5mm for you to easily design alternate attachments.

A video demo of how to assemble the box can be found here: