alpinelakespilot2000
Well Known Member
One technique I've had difficulty with, after having got through the wings and much of the fuselage skeleton already, is how to accurately center large holes drilled with the unibit. It seems like I can never get the hole EXACTLY centered where I want it. It some cases this doesn't matter much, but in other cases Van's leaves us with very little margin for error regarding edge distance. Some of the bulkhead holes come to mind here where, if your hole is any more than 1/32 off center, you might be left 1/32 shy of the usual 1/4" needed for edge distance by the time you get a 5/8" hole. Thus my question is about the best technique to drill up to size...
In most cases I've started with Van's predrilled hole, if it exists, and drilled up to 1/4" using a couple of intermediate sized bits. Once it's at 1/4" then the pilot cutter of the unibit should be centered. Even doing it this way, though, does not always seem to provide perfect accuracy. Sometimes I'm right on, and sometimes I'm not by the time the hole is drilled up to full size. Again, being 1/32 or sometimes 1/16 off by the time I'm done doesn't really matter, but sometimes it does.
Any suggestions for tried and true methods to getting big holes EXACTLY where you want them? This is one of those cases where I, as a relatively experienced builder now, find myself somewhat humbled.
Happy Super Bowl weekend! I've been waiting a long time for those Seahawks!
In most cases I've started with Van's predrilled hole, if it exists, and drilled up to 1/4" using a couple of intermediate sized bits. Once it's at 1/4" then the pilot cutter of the unibit should be centered. Even doing it this way, though, does not always seem to provide perfect accuracy. Sometimes I'm right on, and sometimes I'm not by the time the hole is drilled up to full size. Again, being 1/32 or sometimes 1/16 off by the time I'm done doesn't really matter, but sometimes it does.
Any suggestions for tried and true methods to getting big holes EXACTLY where you want them? This is one of those cases where I, as a relatively experienced builder now, find myself somewhat humbled.
Happy Super Bowl weekend! I've been waiting a long time for those Seahawks!
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