The edge spring was tested on Passap Duomatic S but it should work on any compatible machine. The dimensions are kept as close as possible to the original one, apart from the added support to make the actuator arm rigid.

The part requires a ballpen-like metal spring. I used 4mm x 0.4mm x 20mm from Aliexpress but a bit shorter one (around 15mm) should be much easier to assemble.

Assembly works as follows:

1. Print the edge spring button in contrast color

2. Print the edge spring in main color, with the pause right before the bridging layer (13.4mm / layer 67)

3. Put the spring and the spring button in the opening, making sure the spring is fully inside

4. Continue the print which will seal the mechanism

Some notes on the printing process:

• None of the parts require supports: edge spring button should stand on its square side, edge spring should lay on its "arm" actuator 

• Print multiple buttons at the same time (I printed 9) to avoid the heat creep as this part is very small

• When printing the edge spring, rotate it so that the button hole is in front of you for easier assembly

• I had a bad join line when using PETG while PLA worked much nicer. Consider adding a sacrificial part which prints first to build up nozzle pressure after the pause.

• Assembling the spring is a bit painful, it flies away really easily. I put the spring inside the button first then compress and bend the spring a little so that the button goes through the hole.