Started prepping the retract gearbox for LH wing. I had done a quick cleaning on the retract gearbox when I unloaded and did inventory. I really cleaned it well today using a brass bristled brush and some brake cleaner and rags. The gearbox is truly a work of art. It's a shame that it will be hidden away in the wing once done. It's amazing, even after 50 years it still runs as smooth as butter.

The retracts are operated by a single motor in the fuselage. The motor runs through a gearbox with outputs running outwards towards each wing. Each of these outputs are connected via a torque tube to the smaller splined input shaft of this gearbox. This gearbox is mounted behind the spar and a shaft runs forward, through the spar to a series of levers that raise and lower the gear. See Nov 4 entry for a brief description of the operation of this unique retract system.

This gearbox is geared 37:1. That is, the input shaft must complete 37 turns for 1 single turn of the output shaft. Lots of mechanical advantage there. It will be interesting to figure out the ratio of the gearbox that's in the fuselage that takes the motor output.

This gearbox is mounted to the backside of the spar with 4 bolts that run through to the pad/bushing on the front side. The bolts for this plane were custom made by Dalotel. Just like everything else on this plane. I've found drawings of these bolts in the 300 pages of drawings. They are effectively AN5 bolts. I'm going to replace them with new bolts as these ones are showing some surface corrosion. The "shorter" ones can be ordered as AN5-60A from AC Spruce. The longer ones would be AN5-80A, the longest AN5 bolts made. It looks like those critters are available but they may have to be sourced elsewhere.