Hi Will,
Glad you joined the discussion. Your timers are working very well for me. The one in my B ship has the pushbutton bypassed since, somehow I managed to have a drop of CA fall on it. Anyway, your suggestion of a rod moving forward on brake application at the right side of the motor shaft axis, to intersect the prop (or perhaps a contoured spinner backplate) is the best so far.--Maybe a disc with two holes.
As things stand now, my airplane (pictures elsewhere on the Forum) has a forward wire skid long enough to protect the prop, but soft enough to bend on every landing (either I land too hard, or the length of 1/8 music wire was not properly tempered). I have now made a plywood panel, carbon fibered to the front of the wire and the bottom of the fuselage. Since it is close behind the prop, its contoured like a stator in cross section. Possibly it will stabilize the wire enough, and recover enough momentum to null out its' drag. We'll see at the December meet.
I don't want to reprogram my CC ESC for brake yet, but will try the brake after the meet. If the prop stops for me, the next step would be to discuss the prop-stop function.
Best regards, Will Stewart