The steering blocks were found on eBay and purchased for a relatively small amount. I don’t remember if the claim was that they were made by MIP, a very coveted maker of RC10 hop-up parts. (On my list of aspirations is to acquire a 4WD kit made by MIP for the early RC10.) The steering blocks are designed beautifully. Instead of using two #8-32 7/8” flat head screws in this location you replace them with screws of only length 9 mm or so. The kit comes with two shoulder bolts that are actually a cross between a shoulder bolt and a standoff. They screw onto the chassis through-screws from the top and provide a very precise 1/4” diameter cylindrical surface for ball bearings. The same size flanged ball bearings as what is used on the rear axles are used here. The original shallow white nylon nuts that came with this kit had one side of nut with a cylindrical offset that matched the inner race of ball bearing well, not really touching the outer race. However, there was a bit of slop/play on the shaft – the bearings were free to travel about 0.5 mm up and down the shaft. Having run out of conical washers used on the rear axles I employed carefully chosen black o-rings to provide a slight amount of bearing preload. The o-rings are only touching the inner race and not the outer race. Aluminum nuts secure the assemblies from the top. The nylock material on these nuts is particularly tough – the nuts won’t come undone by themselves. The pressure of the nuts onto the o-rings is carefully calibrated to allow a relatively resistance-free rotation of the steering blocks. Best of all there is no perceptible play in the steering blocks. The center linkage consists of DU-BRO #4-40 ball swivels, with conical washer not needed and not installed. This is DU-BRO part #2161, in black. The ends of the black plastic eyelets were cut about 2 mm to allow them to butt up against each other just as this connecting tie rod reached the ideal length.
The aluminum wing tubes on original car were battered in with a hammer and were severely mushroomed at the ends. It was not a pretty sight. I took them out and reshaped them. I made sure not to remove more than 0.5 mm of length from the overall length of tube, and I made sure to leave them at exactly equal lengths. The end that was battered was ground to a flat surface again and beveled at a 45 degree angle just a touch. A very shallow taper was added to the last 2 mm of tubes to allow the tubes to fit better into the rear bulkhead holes. The healthy end, now sticking up and previously inside the bulkhead, was also made to have a flat, smooth finish at the end and a very minuscule 45 degree bevel was added just to make them look extra nice. Even if you took the tubes out of the bulkhead and examined them there would be no trace that they were once battered in with a hammer. I got them in carefully by having some soft wood between hammer and end of tube. The wood will deform much sooner than the aluminum will. They’re in as far as they will go. They are bottomed out in the holes in the rear bulkhead. They’re sticking out equally, as measured with a caliper. We’ll find out how well they’re positioned when it’s time to mount the body.
(Continued in next post.)
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