EC-18C:
Have you considered using either the arduino pro micro with a diode matrix instead or the Leobodnar boards?Using the pro micro and the mmjoy software (MMJoy/MMjoy2 - Set your own USB controller with a cheap Arduino - SimHQ Forums) you can have more than enough inputs for your project. I myself am considering to make an F5E control box for the main functions and I am planning to use this method.
Leobodnar boards (www.leobodnar.com) come in various sizes and characteristics (to build a joystick, button boards of 32 and 64 buttons, etc) and use another type of SW where there is no programming needed.
You can look for both solutions on youtube and you will see there are no issues with the bouncing.
Hope it helped!
My first idea was along the same lines but i realised that i don't want a custom game controller but a two way system. I knew about the mmjoy but not the leobodnar stuff. At least i know now where to buy a dual encoder.
Thank you for the links i'll save them till later.
I still would like to roll my own which is half the fun.
I am aware that there are a lot of ready made stuff available for cockpit builders but i'd like to make my own.