Nothing new here... but it might give people some ideas.
I put the warthog's grip on my old uni joint stick (see
http://www.jpfiles.com/hardware/uni_stick.pdf ) This stick doesn't have any centring spring, which might sound strange, but I don't mind it at all. The stick and stick adapter's weight give it a good feel.
The ADC is a BU0836A, with duplicated 25 pin sockets to input the hall effect sensors and joystick buttons.
I wasn't happy with the out-of-the-box warthog stick movement. Even after I removed the larger spring, the clunk (from new) when crossing the centre point was just too much. I also felt that the static friction was too high - requiring too much force to get the stick moving - which often meant overshooting the desired position. This was particularly noticeable when air-to-air refueling in A-10C, and with the fine controls needed for UH-1H.
It's all mounted on aluminium extrusions, which allow easy adjustments to critical dimensions, and are quite rigid. Previously the warthog stick was mounted on the right side, like the throttle in the following photos.
The pedals are supported and pivoted by a lazy susan bearing. Unfortunately this bearing has too much lateral slack, so I will replace it with something else.
I also need to add another support to the stick mounting pole - it can tilt forward or back if you place too much weight on the stick. Laterally it is rigid.
The warthog grip is easy to re-wire, owing to the switches all having wires that run to a circuit board, and consistent colouring. I needed to plan this one, rather than my usual thinking while soldering! I also used diodes, but probably didn't need to. I can post the connection list if anyone wants it.
a few cable ties later...
I had an adapter turned up by a machine shop, to fit in the drive-shaft of my stick base. It just needed a few layers of electrical tape to make it tight when in the drive-shaft.