Pedal assembly

Today started with some general cleanup. I still had the pile of tubing scraps from yesterday’s photo op, in addition to all the tools and various other related stuff lying around. So it took about half an hour to get to a point where the workbench was usable again.

The pedal system is relatively straightforward as systems go, but still mildly time-consuming to construct. First, small pilot holes are final drilled to #12 for the mount points to the forward floor and firewall. Then the assembly is bolted in place temporarily and mount holes between the slide bar and end socket are drilled. The whole assembly comes out, stuff gets deburred, and then it’s time to drill the assortment of position holes in the slide bar. These hole determine the possible positions of the pedals.  The plan method here is a bit convoluted for my taste; they want you to drill the forward- and aft-most positions, disassemble everything, mark the positions of the remaining holes, reassemble, and then align the pedal with each mark and drill a hole at that point. It seemed a lot easier to me to measure the length of travel, mark the exposed slide bar at appropriate intervals, and just slide the pedals to each new position to drill. So that’s what I did.

Here’s the slide bar marked for each position (sorry for the blurry photo):

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And a look at the holes with the pedals in the aft-most position:

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Next, the rudder pedals go in place. The pedals are retained by plastic end blocks which bolt through the rudder pivot bar; these blocks are carefully positioned and then bolt holes are drilled through the pivot bar. Disassemble, deburr some more, and then the pedals go in place permanently.

Then it’s time for the brake pedals and master cylinders. The pedals themselves are welded aluminum units, and like anything in the kit made from thick aluminum, the edges are pretty nasty. So I spent a fair amount of time cleaning up the edges. Then the master cylinders have to be prepared by installing the brake line fittings. The fittings are clocked slightly inboard to provide proper clearance:

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While the pivot points for the brake pedals are predrilled, the hole to connect the upper master cylinder is not. The plans call for a specific location, and note that pilots with large feet may wish to drill the holes a bit higher to avoid inadvertent brake application. I don’t think my feet are that big, but I don’t want inadvertent brake application, so I drilled the holes 1/8” higher than specified.

I actually messed up a bit here. The instructions only have you drill one pedal to start with, then put everything together with the pedals aligned, and then the hole location in the other pedal can be marked. This is to ensure that both pedals are aligned. Well, I just marked and drilled both pedals before reading this bit. But after temporarily assembling everything, the pedals still align OK, so nothing to worry about here.

Here’s the final assembly from the aft (pilot-facing) side:

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And from the forward (firewall) side. Note the tape over the brake fittings – I don’t want any foreign material getting in there!

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And that’s a good day’s work. Next up, I’ll put together the locking mechanism to finalize the adjustment functionality. I also need to finalize all the bolts and add cotter pins where appropriate, but before I do that, I want to prime and paint the pedals. I briefly considered having them anodized, but decided that just using the same interior paint as everywhere else will work. It’ll also provide a slight bit of anti-skid roughness – not enough to impede sliding my feet on and off the brakes, but to help keep my feet in position.

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