Twisted off PTO shaft repair.

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Was using my 1957 Case model 77 pull type combine to combine some oats for a friend today. Hit a slug of oats and plugged the combine and the PTO shaft twisted right off. The combine and tractor were properly matched so I don't know why it happened. Would have been nearly impossible to find a replacement so I just fixed it. I cut the damaged ends off and found a pipe that fit inside to use as a filler. Clamped it to a heavy angle to keep it straight till welded. Drilled some holes for plug welds and welded those and around both ends. Then welded 4 straps on for extra strength. Turned out good and works fine now. Attached Images
Reply:For sure it'll never break there again.What happened to the shear bolt or slip clutch that's supposed to prevent that from happening in the first place?MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:I was thinking the same Duane.  Although my WD Allis can't shear the bolts anymore anyway - engine clutch just starts slipping Nice repair man - looks solid.  Bonus points for using scrap Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:Necessity being, as we know, the mother of invention, nice thought process to fix it and nice work doing it.
Reply:hows the ballance?Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:Originally Posted by Dualiehows the ballance?
Reply:Is this the main pto shaft that connects to the tractor? 540 or 1000 rpm? I had a shaft get slightly unbalanced on my discbine (1000 rpm) and it only took one day of use to cook the bearings in the 50 degree CV. If you're running it slow, it may not matter. High speeds may cause problems.Lincoln Precision Tig 185Lincoln Power Mig 256Hypertherm PM 45Everlast 140STSmith O/A
Reply:Being a '57 my guess is a 540. Especially a shaft of that length but that's just a guess.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:It's a 540 shaft but only runs at 500 rpm's. I don't think balance is going to be an issue. Besides it will only be used a few hours a year.
Reply:No shear bolt, it's a flat belt drive and the belt is supposed to slip. Guess it was to tight.
Reply:A slip clutch is available that may fit on your shaft. The one below comes in splined and smooth connections.You may not want to spend that much on something seldom used and with a system (belt drive) that is set up to protect the drive line.http://www.tractorsupply.com/en/stor...t?cm_vc=-10005Last edited by GWD; 08-14-2013 at 08:52 AM.Reason: forgot link
Reply:The belt probably was not too tight. My guess is a shaft with that age, bouncing through the fields for a few decades just experienced fatigue and gave up. I had a forage harvester pto shaft snap in some of the most even corn I've ever chopped. It was a 1000 rpm machine and snapped in the solid hexagonal portion of the shaft. The machine was 22 years old at the time and was worth more for scrap than trading in, so I welded it up the best I could while waiting for a new machine to arrive. The repair did its job, and now I'm 10 years into the new machine and looking for fatigue to start again (I'm covering twice the acreage my father did).Lincoln Precision Tig 185Lincoln Power Mig 256Hypertherm PM 45Everlast 140STSmith O/A