How much PTO shaft overlap is safe - slightly different issue

   / How much PTO shaft overlap is safe - slightly different issue #1  

davesalisbury

Member
Joined
Jul 28, 2006
Messages
43
Location
Xenia, OH
Tractor
Kubota B2630
Hi all-

Long story for setup...

I have about 3 acres of "non lawn" that I'd like to hit about 2X per year. Just hitting it with a bush hog means it looks ropy (it gets pretty tall). I found a sickle bar mower (one of the old IH models with a rear wheel and a bar across the front, apparently designed for a Farmall-type mount) for $DIRT cheap (everything looks good so it should work), took the bar off, put on 3PH pins, bolted a chain on to lift the top and it works with my quick hitch (as an aside, HOW did I EVER live without the QH?). This would allow less frequent cuts, yet leave the field looking a little better (before anybody asks, nobody seems to want to simply mow it in exchange for taking the hay that I could find :confused: ).

Unfortunately, the PTO as designed is too short to reach on my B2630 (even without the quick hitch). Each 1/2 of the shaft is about 9.5 inches (13 inches after a minimum safe overlap), and the reach now needs to be more like 39 inches. The shaft pieces are rectangular, with the big side being 1 1/4" by 1 3/8", and the smaller side being 1" X 1 1/8".

I have two ideas...

First is to simply buy a longer "big side" (enough to overlap by 6" leaving 3 1/2" for slack) and swap out the bigger side. Would probably need a machinist (I could probably do this but lack the tools). This would make the overlap asymetrical, so I guess that's question 1. Would this be acceptable/safe?

Second is a bit more complicated, but should mean a more symmetrical overlap if I'm thinking right. Buy a tube the size of the big tube, then let it overlap the smaller tube by 6 inches). Buy a tube the size of the smaller tube, then have that welded that to the "new" big tube after overlapping 6 inches inside that. It'd then stick into the "old" big tube by at least 6 inches. In essence, there'd be two overlap points rather than a single one. This way I have the mower in original condition should one of those old IH Farmall types want to buy it for a price that'd let me get a regular 3PH mower :)laughing:). Is there anything inherently dumb about this idea (besides the resale plan)?

As always, good ideas, ill-informed speculation and evaluation of my ideas are welcome and indeed encouraged.

Best,

Dave
 
   / How much PTO shaft overlap is safe - slightly different issue #3  
My paperwork said "check for 4 inch overlap" it is about 3 inches, So?.
 
 
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