As with other parts of the locomotive chassis that I acquired I decided to replace the original truck and frame bolsters with those that Bob Reedy designed. One reason being that the originals were poorly made from aluminum castings. I was concerned that they would fail in a derailment. The other reason was that the truck bolsters were sized for 7-1/4" gauge and did not leave enough room to move the wheels out for 7-1/2" gauge. Old aluminum bolster shown on the left, new truck bolster in center, new frame bolster on the right. New bolsters were TIG welded rather than silver soldered.
In the USA we are stuck with two gauges for the larger scales. If you look back at my Shay pages you will see a dual gauge arrangement for the Shay proposed by LocoGear using threaded axles and moveable keys to allow one wheel to move 1/4" to accommodate either gauge. I decided to adopt this method for the Climax. New, longer axles were made as well as a hex bronze nut and a brass key to reduce the problem of rust preventing their movement.
Some progress on the gears and cross bearing assemblies (3/23/14):
End Frames: I use the Ken Schroeder method of making arch bar trucks to make the truck end frames. Cut part way through the material and bend it in your hand. You can make very accurate bends that way. Then weld the open part of the bend. Grind off the excess and then machine the part. I still have to drill holes for the brake hangers. Any imperfections in the ground down weld will not show when painted. (3/29/14)
Universal Joint Housings: These are slightly larger diameter housings than Bob Reedy's design because the PLC gears have taller horns on the pinions. One of the adjustments that need to be made when using parts from different sources. The two end pinions in the driveline do not need the horns so I will cut those off and use them on the shafts. The housings were made on the cnc mill. Bronze inserts will be made for the ends of the horns.(4/23/14)
Trucks being assembled. I have the two trucks without side frames with their drivelines essentially complete. I added a spacer and Teflon washer between the cross boxes and the axle gears. The axle clamps have Teflon washers where they run against the axle boxes. These work well as everything turns freely. The assembled truck doesn't have the driveline finished yet but the axle clamps are shown in the lower left of the last photo. One clamp is threaded where it fits over the threaded portion of the axle and the other clamp is smooth. The threaded clamp is a two piece unit so it can be removed to allow the gauge change. This is only needed on three of the axles as the gear is on the other side on the other three axles. (6/6/14).
All three trucks completed. This has taken a lot longer than I thought. New gears work very well and look great. (7/21/14).