On 7/3/2013 2:15 PM, Steve W. wrote:
....

Would plow bolts work?

http://www.plowbolts.com/shop/bolts-6696

I had suggested that as a possibility earlier, too, but again it's
unlikely to find one in 9/16" (and he'd have to round the corners or
broach a square hole). 1/2 and 5/8, no problem; 9/16 is a pretty rara
avis (I don't recall ever seeing one on anything). 7/16, otoh is fairly
common on farm equipment as the difference in cross-sectional area
(hence strength) of (7/6)^2 is 35% whereas all the way to half from 3/8
is nearly double and that is often overkill. OTOH, the difference
between half and 5/8 is a little 50% which isn't so bad and so it
rarely (as in never) is fine-tuned to the point of specifying 9/16.

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