*Tzing*
Can you hear it ? ^^
The first one working ! I couldn't stop pushing the key ! :D

Now for the explanation : the quills, if you let it raw, will not work properly, making a hideous noise while going up and not going below the string afterward (thus making it hard to play again).
That's why you have to carve the quill a little, making it thinner and thinner until the sound it makes is strong enough to be heard while being "smooth" and fluid for the mechanism.
This is a real science, and I'm learning how to do it with each jack done. ^^
This process is called the harmonization.

I'm currently working on the jacks as fast as I can, and I will make some records of how it sounds once I've enough of them installed. ^^