Installing those hundreds of rivets in the side skins went mostly without a hitch, although my beloved pneumatic rivet puller did have an uncharacteristic hiccup. After the first 50 or so rivets it quit releasing the steel arbor after breaking it off the rivet. I disassembled, cleaned, lubed, and re-assembled the puller head several times to no avail. Finally, for no discernible reason, it started working again. The aviation division of Harbor Freight sells a cheapo puller (~$35) which some builders swear by (although it will probably rust before you get it home from the store). I may get one of these as a backup before I start on the wings, which involve a sea of rivets. The stiffeners required by the landing gear service bulletin require some CherryMax rivets which none of my regular pullers, manual or pneumatic, would set. The manual puller made by Cherry (discussed in a previous post) again worked well. Between those and all the Cleco installation and removal, by forearms got a workout.
Pulled rivet removal technique. Van's writings on the subject insist that when drilling out a pulled rivet, the steel pin (arbor) in the center should be driven out using a pin punch inserted into the manufactured head, followed by drilling out the aluminum rivet itself. The thinking is that if the drilling is done with the arbor in place, once the bit hits the steel it will go to one side, making the hole oblong. Of the thousands of LP4-3 rivets I've pulled, I've had to, for one reason or another, drill out maybe 50. I've always done it like this: Using a #30 bit with very slow drill speed and light pressure, drill the manufactured head until the head spins under the bit. At this point, what remains of the rivet (arbor and shop head) can be pushed out with very little force. No pounding involved and no chance of denting the thin aluminum. I've not had a single problem with this method.
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