Additional pedestal binder bars were fabricated, three identical sets for the Front, Intermediate and Back driver slots and a slightly longer set for the Main driver slot. The Front driver set is shown cleaned up ready for use while the remaining three sets are still attached to the raft/support structure. The binders are easy to remove by hand but do have a series of stripes of residue support material that required removal by sanding with the Dremel sanding wheel.
The above photo shows the slight difference between the Main driver slot binder at the top with one of the other three binder sets. The difference is small. The wider Main driver slot accommodates the larger diameter bearing and axle.
The binders were trial fit using undersized 1-72 machine screws. The screws for final assembly will be 2-56 after the frame is tapped. The smaller screws fit snug enough in the pilot holes to stay in place, but have little strength.
The Front driver set is shown with binders secured in place using the 1-72 machine screws.
The remaining sets of binders for the existing portion of the frame consist of one set for the Intermediate slot and one set for the Main slot. The Main slot binder is slightly longer.
The machine screws were first run into the binders flush with the mating surface. In one or two cases the holes are almost loose.
The frame holes are slightly smaller and require slight force from a small #00 Philips screwdriver to drive into the frame holes. Care was taken to avoid over-tightening and removal of material so that later tapping with the 2-56 tap will be more firm. The Intermediate driver set is shown above installed with binders held in place with 1/72 machine screws.
The Main driver binders were also installed in a similar manner. Note that all drivers now have residue material removed and are ready for painting as are the binders and frame assembly. At this stage the overall assembly can be handled without having driver sets fall out. The drivers have a noticeable amount of vertical play which will allow the spring equalizer systems to work when the wheels move over uneven track as in the prototype. None of the spring equalizer system is yet installed, however, the bearings have slots to mate with the spring brackets and the brake hangers have holes for the beam fulcrums.
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