Today's Progress:
Today I began making elements of the Tilt-brake.
The square plate at the back will be cut to a round and welded to the headset tube that forms the main pivot.
A standard disc-brake caliper will be used to apply the tilt-brake/lock function and will be operated through a friction-shifter on the handlebars.
The mounting holes were drilled & tapped for M5 bolts.

While a complete disc-rotor has been accommodated at this time for construction purposes and rotor mount alignment to a caliper, the actual finished item will probably be less than half of a complete rotor.