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Oversized bolts?

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asport22

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So I made a rookie mistake. I was drilling wing attach fittings for the Acro Sport II, and mis-read the drill chart. 5/16 is 0.3125. Number O drill is 0.316. I interpreted "16" as being smaller than "25", and drilled the first hole to number O, thinking it would be a few thousandths smaller than a 5/16 reamer. Seemed like the reamer went through pretty easily - and then the 5/15 drill rod I was using to check with was pretty loose in the hole. Should have used a number N drill, of course.

So now I've got a 0.316 hole where I should have a 0.3125 hole. I'm pretty sure I have read about oversized NAS bolts, but can't figure out what they are called to find them to order. The other option is to go up to a 3/8 bolt, but I haven't checked edge distance yet. Is edge distance for the steel fitting the same when it is bolted to a wood spar instead of another piece of steel, or is the crush strength of wood enough lower that the edge distance is reduced as well?

Thanks!

Warren
 

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