Originally Posted by
callsign222
Simplicity is good!
Why can't you guys mount it on the outside of the transom with a couple of burly J. Michalak-like mast partner/step? If you keep it close to the centerline and keep the mast skinny, a mounting plate for the rudder gudgeons for maybe an extra 1/4", and all the problems (as I see them) are mostly solved, and the integrity of the aft watertight chamber is maintained without a bunch of extra structure and points of potential water-entry and weakness. Just a thought from the amateur.
Edit: Obviously the transom ply would be backed up by something thicker on the inside for support...