Saturday, June 18, 2011


A quick trip to Lowes to pick up the appropriately sized tap allowed me to continue on with the fabrication of the control pushrods. If you recall, they had been drilled out to #3 during the last work session and were ready to be tapped. The new Lowes tap worked better than the Harbor Freight tap (Harbor Freight: Home of Approximately Sized Wrenches and Soft Metal Taps) which had insisted on starting me out with a cross-threaded hole from the get-go rather than letting me create one myself later when I try to force a threaded bearing into it from an awkward angle.

Aw, come on. You know as well as I do that it's a distinct possibility, if not quite an inevitability.

I also like the tap driver that I picked up at Home Depot a lot better than the one that came in the Harbor Freight kit. I would have better luck driving a tap by stuffing it into a stick of butter held lengthwise than I ever did with that horrible tool. The beauty of the one I have now is that it will accept a ratchet wrench. Note that this requires a much higher level of patience and caution than would a normal tap driver because of the vastly increased leverage available from the ratchet wrench. I lubed the tap accordingly and used the searing heat of the aluminum tube to gauge when I needed to back the tap out for cleaning. I'm not kidding: that tube got hot!

I then ran into another of those inexplicable cases where the usually superb build manual really caused some head scratching when I tried to figure out why they had me do things in such an unproductive order. You may remember that I had been instructed to "temporarily" install the control sticks in order to complete the wiring for the push-to-talk (PTT) switches. Well, as it turns out the completion of the PTT wiring makes the installation of the control sticks anything but temporary. Unless you're willing to cut the wires, those sticks are in there to stay.

You may remember that I couldn't get the bolts to fit through the bushings, nor could I get the sticks to fit easily within the brackets. I decided to skip dealing with the bushings at the time since the sticks were only being installed "temporarily." I found out today that there was no hope of the bolts ever fitting through the bushings; the bushings had to be drilled out with a 1/4" bit. In the next step I found out that there wasn't much hope of the control sticks fitting into the brackets either since the plans required me to file down the bushings so that they would fit between the brackets, then file down the tubes on the control sticks such that the bushing was just a touch wider. It makes me wonder why all of this filing and fitting hadn't been done before the PTT wiring. I say "it makes me wonder" in a purely rhetorical sense: I know exactly why. Van's puts precedence on keeping jobs in logical sections of the manual rather that putting them in a logical order. The PTT wires had to go in the "Wiring" section, even if it made more sense to do it in the "Controls" section.

This is why they encourage you to read ahead. I have no one to blame but myself...

That said, note that when it comes to filing a steel tube, there are better locations to do it other than inside the guts of the airplane. I haven't thought it all the way through, but it seems to me that there had to have been a better order of progression that would have avoided this and it might have become apparent if I had read ahead. As it is, I had to resort to the Dremel tool to get the filing done.

Quite a bit of filing later, I had just a titch of bushing showing on each side of the control stick tubes.

I dug out the nuts and washers needed to bolt the sticks into place. Finished! All that was left to do was hoover up all of the nuts that I had dumped onto the work bench while searching for the correct sized nut (needle) in a bag full of dozens of other nuts (haystack). That's when I let my attention lapse. It wasn't much later that I realized my mistake: I had scooped up all of those nuts and dumped them into the washer bag.

This was a problem. I view nuts and washers like a horseman view colts and fillies: you really want to keep them separated until you have just the right pairing for them. There was nothing I could do but dump the whole mess out and sort the nuts out from the washers.

These are the completed pushrods. These will attach the pilot and passenger control sticks to the oddly shaped pieces that I installed last week and provide left/right input to the flaperons.

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