Main Landing Gear Thrust Bearings

I decided to install thrust bearings on both sides of the MLG pivot bushing to prevent the metal-metal (bushing to bolt-holder) contact and potential wear and slop in the MLG system. This mod was first described by Dale Alexander in the Builder’s Forum section of Velocity Views 1Q 2004. To accommodate the width of the thrust bearing, I had to grind down the existing steel pivots that have already been glued into the gear legs. Care was taken to grind only enough to fit the bearing in place, and to maintain the position of the gear leg on the pivot bolt (because the retraction mechanism has already been fit). The grinding was followed by fine filing to make sure that the remaining bushing edge was flat and perpendicular to the pivot axis.

After the thrust bearings were installed, the MLG legs moved very smoothly. The side of the fuselage and portions of the gear pockets were trimmed to allow the gear legs to retract fully without interference. Adequate clearance between the gear user legs and the sump tank fittings was verified.