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Comment to Dick Perry:

Granted that the wing bolts are not loaded in tension - but you certainly
must bring them up to the correct torque upon installation. At the correct
torque, incorrectly manufactured bolts (cut threads), even when loaded
primarily in shear are more likely to develop cracks because their strength
is well below normal. As i've said many times before, "You pays your money
and you takes your chances". Just because these bolts are loaded in shear,
doesn't mean they should be of lower strength than correctly manufactured
units. At the very least, if you elect to use the bolts with cut threads,
you'd better inspect them frequently (assuming you have a sound method to
accomplish this, since finding incipient cracks at the thread roots is not
easy).

Dan Schaefer

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Please send your photos and drawings to marvkaye@olsusa.com.