2.5 hours.
I win. Sweep and incidence are set, aft wing spar bolts are in. I made a drill guide from some 5/8″x1x4 bar stock (which I’ll have to replace, I think it goes with the wheels or brakes) featuring holes of 17/64″ and 5/16″ to guide the middle and final steps of drilling.
But about that stuck drill bit. As I suspected, I was able to drill just below my ‘relief well’ and pop the broken bit out from the front. Once I drilled it with the 5/16″ bit, all traces of nastiness went away and I have a nice round hole with little to no play on the AN5 bolt that goes in there. On VAF, there are a good amount of people who recommend using a .311 reamer to obtain a close-fit, precision hole. There are also a good amount of people who say that using the plans-recommended 5/16″ bit works fine too. I don’t have a .311 reamer. I don’t want to buy a .311 reamer, or any other kind of reamer right now, and I certainly don’t have time to wait for it. I think the drill guide did the job, and as long as that bolt is torqued and cotter-pinned, I seriously doubt the wing will fall off. If it should come to pass that the wing wiggles around that bolt, I’ll go up to the next size, use a reamer and a NAS close-tolerance bolt, and that’ll be the end of that. But there are plenty of RV’s flying with 5/16″ holes in their aft spars and they don’t seem to be having much of an issue.
I’ll have to take the wings off again to deburr the holes and shoot some primer on the raw metal where it was drilled or filed, as well as do the lineup for the wing root holes, but while they’re on, I’m going to do the flap pushrods, the rudder cable links, and maybe just for giggles, put the wingtips on to make sure everything lines up along the trailing edge.
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