"Christopher Tidy" wrote


Yes, you would need to ensure that the bottom bearing can handle the
horizontal force if you go for the "stiff leg" type of crane. But if you
use your original design without a stand-off part way down, your bottom
bearing will carry a horizontal force. It would be a good idea for it to
be capable of carrying a horizontal force anyway. If you can resolve these
small problems, and you don't need to lift bulky loads to the full height
of the crane, I think the stiff leg is the way to go because it will be
strong and reliable. If you stick with your original design I would put
one stand-off at the very top and one a foot below it, as opposed to the
way they're shown in your diagram. This will mean that the vertical column
isn't being bent at all, which is a good thing. I think this is more
important than having a stand-off in the middle. Also, make the stand-offs
adjustable so you don't have to force the thing together in the first
place!

Best wishes,

Chris


One of the design criteria is that when the load is at the top, right before
it hits the winch kickout switch, the load needs to be swung into the porch
over the 36" high handrail. A stiffleg wouldn't make it in to where the
load could be landed on the deck before it hit the side of the deck. This
needs to be lifted to its highest possible point, and then swung about 150
degrees over the rail and inside the railing, where the load would be hand
unloaded, or lowered to a waiting dolly.

Your suggestion would work perfectly IF I didn't have to have that extra 60
degrees of swing.

Steve