Beginning on June 11, knowing Kieran (our uncle who was coming for a visit) would want to do some work, Mark got back out into the garage (despite the 100+ degree heat) and was able to devote more than a couple of hours to the plane. Being a good host, Mark knew that it would be best if there was some real riveting to be done (rather than hours of deburring) and therefore tried to get some pieces ready for this. As chance had it, the four flaperon hinges were the best option as they need some squeezed rivets to hold them together. Mark worked on all of the prepping including deburring edges, holes, roughing up, and priming.
Mark spent the next morning getting the pieces together and making sure we had the correct rivets out. This is always a bit of a pain because Van’s ships the hardware in numbered bags that quite often hold a variety of pieces. As a result, when we first receive the subkits and work on the inventory we put the little bags into individual bins and label the bin accordingly. When Mark gets to the point in the construction that requires the specific piece he need only cross reference the shipping list with the bin number to ensure that he has the correct piece of hardware. Now please remember that it has been about eight months since we inventoried the wing subkit. . . .so. . .he found the correct bag and identified the necessary rivets, but they looked too long. Using calipers, he found that they actually were the wrong rivets and that somehow, we had received the incorrect size when the wings were shipped. While we inventory all of the pieces, we spend no time identifying the hardware as it would take days to confirm. This is the first error in shipping and while it is inconvenient, the actual rivets themselves only total a couple of dollars. Unfortunately, what this meant is that Kieran only had the opportunity to squeeze about 8 rivets. This may have worked in his favor however, as they were AN470AD4-4’s (for those of you who can't translate from aviation rivet language to English, that means they are pretty hefty rivets) and they need your full body weight to set. This gets a bit tiresome after the first few and 8 might have been just the right number. The piece he worked on will be visible and we will for sure look at it during each preflight.
Additionally Kieran was able to experience some of the less glamorous aspects of airplane assembly meaning that he had to help prep some pieces. There are two flaperon hinge brackets which consist of three beefy pieces of aluminum each which sandwich a bearing. All six pieces needed some work done using the Scotch Brite wheel, hand files, some roughing up with Scotch Brite pads, and some deburring of holes. Mark had to machine countersink a couple of holes to accept a countersunk rivet while the shop head will fill the other countersunk side of the piece. As usual, the machine countersinking is more art than science so this took a bit of time to get it right and not overdo it. Time flew by pretty quickly and before you knew it, Kieran and Marianne had to leave to catch their flight.
After they left, Mark primed the pieces, took a break while they dried, and then returned to squeeze the rivets. He had no trouble doing the squeezing without assistance from me, but the countersunk shop head stood proud of the hinge plate which was bothersom. It was as if the rivet itself was originally too long. In researching this on the internet, it was clear that Mark was not the first to experience this problem. The only recourse is to file the extra bit of rivet that was standing proud of the piece. Mark went into this task knowing that it was going to be difficult to get right and it turns out that this was a self-fulfulling prophecy as he ended up scoring the plate pretty deeply in the attempt to shave the rivets. Although it was most certainly, just a cosmetic issue, together we decided that we just didn’t want to have any doubts about such a critical piece so with my blessing, he ordered a new set of parts to reconstruct this hinge bracket. Better safe than sorry! This is why we both like building our own plane since we fell that our standards are quite a bit higher than most factories.
It was now time to clean up the garage and get it ready for much larger construction and the serious work of getting all of the ribs prepped.
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