Sennheiser Momentum True Wireless Charging Case

How i designed this

1. The hinge on my stock case broke
2. A new case is $100
3. The earbuds cost $100 used
4. …
5. Spent several weeks desinging a new one from scratch

How to print

• I printed it in PETG, but PLA should also work.
• The 3mf file includes tuned support settings that i found to be optimal
• Support removal is a bit tricky with this one, be careful not to damage the model

You will need

• A bit of Filament
• 4 7x1 mm magnets
• 4 M3x12 screws
• Sidecutters or a knife
• Screwdriver with a small philips head and a 2.5 mm hex bit (here's a cool electric one I made an awesome magnetic case for)

How to assemble

1. Pry apart the original case (it uses clips all the way around, can you manage to not break them?)
2. Unplug the battery, then remove it from the bottom part of the case (its stuck using double-sided tape, don't remove it, you will be reusing it)
3. Unscrew the board (fixed with 4 phillips screws)
4. Take 4 7x1 mm magnets, glue them into the corresponding slots in the middle part and the lid (MAKE SURE THAT THE LID IS ATTRACTED TO THE MIDDLE)
5. Take the lid (just the lid) and put a piece of filament though the hinge, cut it to length, then pull it out
6. Combine the lid and the middle
7. Put the filament you've cut though the hinge (this can tricky, giving it a bit of a bend will help)
8. Attach the board to the middle part using the original screws
9. Connect the battery to the board
10. Stick the battery to the bottom of the case
11. Attach the bottom to the middle using 4 M3x12 screws
12. Plug the case in and see if the led in the back lights up.

Issues i can't be bothered to fix

I've printed more than 20 of these to get to this point, and it works fine as is, but there are things that can still be improved

The use of screws

I really wanted this case to be snap fit but couldn't design clips that could hold it together well (or at all, to be honest). I would LOVE to see a remix that fixes this.

The wobbly back plate

The back plate can be bent in with a finger. Mine didn't break yet, but it's probably a good idea to add something that would hold it in place better

The shape of the holes

Since i don't have a 3d scanner, i was only able to model the holes approximately. The headphones do fit and charge, but it's not ideal.

Chamfered edges

This case is actually smaller that the original, but it looks bigger because it has relatively small chamfers instead of fillets that are present on the stock one. The issue with adding bigger fillets is that the battery might not fit in the bottom because of that. I did not test this though.