I am still looking for a good quick safe way to drive SPT's then disconnect them totally and instantly without having to move the headstock at all and reconnect the same way.
One day this week I ran across the unsatisfactory 2 piece coupler I made quite some time ago. It was a regular coupler cut in half with a left hand thread bolt in one half and a left hand thread nut in the other (coarse threads). I just didn't like the result. Not the answer...
This is one of those things where there can be a number of correct answers and the choice between them may be up to individual circumstance and equipment.
I am working on several possibilities quite different from each other.
As a lifetime farmer I tend to draw from that experience first. It's kind of like the saying that if you are standing in the middle of a room full of stuff holding a hammer that everything starts looking like a nail.
On most farm machines that are ran by a tractor they are most often coupled either by flat belt (fairly obsolete today) or PTO shaft. A tumbling bar with a universal joint on each end. Normally one end stays attached to the implement and is coupled to the tractor by extending the other end (telescopes in the middle) and sliding it over the spline shaft on the tractor. There are several different ways to keep the end on the tractor shaft.
This is typical:
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Something like this one should work OK and is much much smaller than the one on the tractor. These can also be made up with safety slip clutches in the line. In using something like this you would add a hanger hook to the SPT so you could swing the shaft aside and hang it off to one side when disconnected:
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I have more ideas but will put them on additional messages.
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