TRF,
Today we tested our thrust plate. It supported more than 10,000 pounds-force with ease.
As pictured below we set thrust plate on a perimeter of bricks representing the airframe. A 1/4-inch thick steel disk representing motor’s thrust ring was bolted through four places. An 8-inch steel tube representing the motor was set upon the steel disk. Scale was placed upside down on the steel tube. Finally a 1/4-inch thick steel square was set upon the scale to distribute load to scale’s 4 feet.
The assembly was subjected to compressive loads from an excavator.
A first compression to 6k scale reading produced no appreciable deflection of the thrust plate. The square steel plate, however, suffered almost an inch deflection. We unloaded the assembly and the steel square returned to flat. Some audible pops were noted on initial loading.
We added a second 1/4-inch steel square to the assembly.
A second compression to 6k scale reading produced no appreciable deflection of the thrust plate. There were no audible pops. Noticed just a little deflection of steel squares.
Finally we compressed the assembly to scale overload, about 10k pounds-force. Again no appreciable deflection of the thrust plate was observed.
Thrust plate was thoroughly examined after loading. No damage was observed including plywood delamination, fastener pull out or adhesive de-bonding.
Feckless Counsel