dpb wrote:
....

A typical small/medium tractor loader is generally a very simple
mechanism ...

OK, I went and dug up the operator's manual off the JD148 that's on the
4440 as the loader tractor here...

http://www.tractordata.com/farm-tractors/000/0/9/96-john-deere-4440-photos.html

It's hydraulics are 2250 psi, lift cylinders are 2.5" bore/1.75" rod --
from which one can estimate max lift force at the lift pin of sotoo
11000 lbf. The published breakout lift force is "only" 4700 lbf in
comparison. It'll handle 2000-lb round bales two-high loading semi's
easily, however as far as the weight; wish the reach were about 6" more,
though, as one has to be sure to have the fork as near the bottom as
possible and if they're just a little loosely wrapped they can rotate
some so maneuvering can sometimes slow one down loading. When there are
nearly a thousand to go; any time wasted, even a few seconds/bale, is
sorely trying to the soul...

I'll try to post somewhere a picture from last summer's haying altho
don't think I stopped to take pictures while actually loading out; had
my hands full of controls at that point...

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