Rudder Pedals!: 11.5 hrs

June 10 & 11, 2020

Today was about pedals, starting with making the brake pedal assemblies. They went together easily except for the one rivet where the squeezer slipped and I messed it up. Not a biggie though.

I found yet another point where the drawings don’t match up with reality. The drawing for the pedals was revised in 2001 to call out AN3-5 bolts for all the pedal mounts and the fuse kit included the AN3-5 bolts for the pilot side. The “dual brake kit” (required if you want rudder pedals on the right side) still comes with AN3-4 bolts. Between the 8 bolts that mount the pedals, I now have 6 AN3-5 bolts and 2 AN3-4 bolts. Since the two different sides of the pedals are different thicknesses, this means that where they want you to use AN3-4 bolts, you end up using 3 thick washers on an AN3-5 bolt to make everything line up correctly. It’s a small detail, but annoying that in 19 years they haven’t updated their kits to match the plans.

Also of note, this is the first spot where you have to ignore the torque tables. If you torque the nuts to the lowest allowable value and then to the next gap in the castle nut, the pedals don’t move. These need to be installed literally finger tight and the cotter pin will keep it from falling apart. After getting everything together, I couldn’t help but drop them in the plane and imagine the finished plane.

The plans call for the brake pedals to sit vertically in the rudder pedal frame. However, we read multiple complaints about how folks tend to ride the brakes due to the pedal being more vertical than their feet sit naturally. So we decided to add a little bit of angle into them, and spent longer than we should have debating what that angle should be.

We hung everything hanging off the table so that we could use some angle-aluminum to align everything. Eventually we decided to put about 5º of lean back into the brake pedals, which put the pedals in line with the bars of the inboard pedals. Once the pedals were in place, we took a short drill bit and lightly marked the hole location through the master cylinder. We took everything apart, drilled the final master cylinder holes, and then remounted everything.

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With the master cylinders in their final location the next step is to drill holes in the longerons to mount them. Van’s suggests drilling several holes so that you have options for the final mounting location after the panel is installed, when access is limited and drilling is no longer easy. So I set out to drill holes block-widths apart, so that the holes can be re-used the pedals are shifted. Well, that worked out fine for the side blocks but the center block is half an inch shorter than the two outer blocks and leads to a mis-alignment of the holes. We’re going to buy a different center block that has the same dimensions as the outer blocks to make this all simpler.

-Paul,
(Total Build Time: 274.0 hrs)

(p.s. we just got the grypmat in the mail today and Kacy is stoked. they’re pricy but they are fantastic. this is one of those iconic pieces of aircraft maintainers that makes the garage feel a bit more like a hangar and reminds her that we are, in fact, building an airplane)