Glenn Ashmore wrote:
That is a good price of the rod but Enco doesn't sell acme wing nuts. You
would have to buy a regular acme hex nut and weld on some rod for handles.
Not exactly the strongest solution.

No, but look at the application. A 26' boat may weigh 5000 pounds, and
90% is carried by the keel on the ground. The other 500 pounds is
divided over the stands.

250 foot pounds of torque on a 1"-8 UNC thread will develop a thrust of
15000 pounds. I.e., enough to lift three of these bolts. Two pieces
of 1/4x1" flat bar welded to the sides of the nut to act as handles can
carry this much torque without the welds breaking. (Of course, a normal
human would have to put lengths of pipe over each handle to generate
this much torque...)

So while bar stock welded to a hex nut isn't the strongest solution,
it'll still be way, way stronger than needed.

I'll also suggest that there's no advantage to using acme thread in
this application. For a given size you get a coarser thread, which
means more movement per turn, but it's more costly and actually has
less strength since the threads are deeper.

Tim
(who's just designed a cradle for a 34' boat.)