If you have Siemens coffee machine, sometimes (4 years) can happen that unidentified parts broke and falls to coffe waste. From this time, brewing coffee is working, but sometimes weird. When you remove brewing unit, usually you see nothing because this part is hidden inside.

After my research, I removed brewing unit, I removed screws and disassemble it to 3 main parts. Left, Right, And center part with mechanisms. Then you see area where are 2 sliders, on the pressing arm and shaft.
I designed same shape as Siemens have, there are small rigs for lubricant moving.

Clean up all siemens brewing unit parts very precisely. Then apply food-grade silicone lubricant on moving parts and little bit on O-rings. Assembly together, tight screws with sense, and try function. You can check in hand, that brewing unit is moving.

During the cleaning I broke small spring cover that covers large spring in central mechanism part. So I did it also.

Maybe sliders and your print material will not fit for you, try +/- 5% rescaling when slicing the model. My next plans are to use IGUS Iglidur material, that is also certified for food and have excellend sliding.

Design is proven, I assembled brewing unit and tested it. Finally with my printer and PLA+, I printed 105% resized model.

Claim - the picture - first picture is from Printables, where you can find similar model, but it is more simple and has no lubricant rigs.