For most people the typing experience itself is the most important part of the keyboard which it is hard to quantify.

So it shouldn't be a surprise that my thoughts circle around that aspect as well when thinking about the PolyKeyboard.

What I cannot influence for now, is the keycap profile from the relegendable keycaps I use. It's maybe close to XDA, however the swale is not that profound, the corners are a bit more distinct and the overall height is only 8mm.

And what about the key-stroke?

How much does the flex cable influence the behavior of the key switches?

To figure that out, I made a little test station and measured how much weight is needed before and after adding the flex cable to the key cap:

The LED on the board will light up when the key switch conducts.

The keycap with the 3D printed stem and the display come with a weight of 2.2g:

My circular tray to hold the weights add another 7g.

First, I did a test without the flex cable, so let's quickly deduct its weight from about 0,5g:

When the LED finally lights up, the following weights rest on the key switch:

Stem with keycap (minus display for the first test): 1.7g

Tray to hold the weights: 7g

Weights: 20g + 20g +1g

That makes a total weight of 49.7g when the switch activates, which matches very good with manufacturer's data for the yellow Gateron switch of 50g for the operating force. So now, how much does that change with the plugged in flex cable? The same thing again, I'm adding weight until the red light turns on:

Stem with keycap and display: 2.2g

Tray to hold the weights: 7g

Weights: 50g + 2g + 1g

Here we have a total of 62.2g, which is 12.5g more. So this is definitely something to consider when choosing switches for the PolyKeyboard!

There is maybe a bit room to get that weight a little bit more down when customizing the flex cable length and maybe also the cable width, but I think the current value of 12.5g added on top of your key switches actuation force is a good orientation.