This is a switch pad you can 3d print for mechanical keyboards.
They are typically made of PORON. However, I wanted to give TPU a try.

Scale the thickness of the pad in your slicer to the thickness you desire.
However make sure the thickness is a multiple of your layer height
(unless using variable layer height.)
For a 0.2mm layer height possible heights might be 0.2, 0.4, 0.6, 0.8, etc.
My first layer is printed at a line width of .62 on a 0.4mm nozzle.
Normal poron pads seem to be a thickness of 0.5mm.

No

No

.2

100%

85A shore hardness