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The recent discussion about main spar bolts started me thinking about the bolts which secure the rear spars to the gearbox. I followed the instructions and started with a small bit, working my way up in size to the 3/8" bit required for the bolts. Now I'm wondering if I shouldn't have drilled undersize and reamed the holes for a closer tolerance fit. At the time I thought that if it was important for the holes to be close tolerance then the manual wouldn't be recommending drilling freehand with an angle drill. Anyone have an opinion on this?

While we're on the subject, I was hoping someone out there might have information to share about when and where it's important to drill close tolerance holes. I realize this is covered briefly in the manual, but I'd like a little more detailed discussion and haven't been able to find it in any aircraft building books. Some builders I've talked to say that if you don't ream every hole in the aircraft your asking for trouble, yet others tell me they never once used a reamer in the construction of their aircraft. I'm sure there has to be a happy medium; can anyone clue me in as to where it is?

Regards,
Matt Erdman

LML website:   http://www.olsusa.com/Users/Mkaye/maillist.html
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Please send your photos and drawings to marvkaye@olsusa.com.