Well, it was the usual "2 steps forward, 1 step back" kind of day. I received a shipment from Van's, but it only had the LP4-4 rivets that I had ordered, but not the replacement tie wrap clips for the ones that I had ruined the other week. I sent off a note to Vans asking for an explanation and/or a shipment.
I was able to attach the 3 remaining R nose ribs with the new rivets without any problem. On the other hand, when I went to attach some clips to the remaining L ribs that needed them I had 4 consecutive failures. For some reason, the tips (shop heads) of the rivets just aren't getting a good grip on the rib and they pull right through and then expand inside the plastic clip. I tried using the hand puller, and both low and high pressure on the hydraulic puller but it just isn't working. I then tried squeezing some 470AD4-7 rivets, but the rib is curved where the rivet goes and I couldn't get it to squeeze squarely.
I think I know what's going on. Rivet holes gets punched at the factory using a tool and matching die. These wear over time so there is a subtle drift in the dimensions of the resulting hole. In this particular case the hole in question is punched into a spot that is then stamped into a curved shape (to provide strength around the lightening hole). I suspect that I have a batch of ribs that were punched slightly larger than typical and then the stamping procedure stretched them just enough that the rivets don't get a good bite as the are pulled and expanded.
I posted my plight to VAF and 2 other builders reported similar instances. One gentleman used an idea that I was already thinking about -- using nuts & bolts. I'll also use some lock tight to secure the nuts. I'll get some at the local hardware store and finish up putting the clips on the left wing wait for the missing clips to do the right.
Going back to prepping the wing skins, I finished unwrapping, deburring, edge breaking and installation of the nut plates to the lower outboard wing skins.
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