how to tackle this repair sickle mower pitman straps

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Hello all, i have a question that needs some expert opinion on how to successfully accomplish this.   I have a John Deere #11 trailer type sickle bar mower that blew a chaincase and wrecked my pitman straps on the flywheel side of the mower.   these straps are avail at JD yet, but they want $95.00 each for the pair of them, ouch!   anyway for those of you that don't know what i refer to, these straps pinch around a heavy roll pin in the flywheel and then hold the wooden pitman stick between the two straps for the sickle reciprocating motion.  These straps seem to be a cast steel of some kind, they are not cast iron and they are not milled or machined steel they seem to be cast the way they are and they are a bugger to weld and stay welded once you break them.  they are not more than 1/4" thick and 1" or so wide.  i am thinking i will attempt to repair them for the cost of new right now.   what you you guys suggest - Tig weld?  DC Stick, O/A gas weld?   preheat before welding, heat after welding?   nickle filler with stick?   i don't know for sure, i want to see what you guys think before i try anything with them?thanks very much all.  i appreciate it.Micheal
Reply:They may be malleable iron. Try to reinforce across the broken area. I don't know that I ever found anything I liked but if I recall correctly, I have stick welded them(maybe 7018) and maybe even brazed them. Problem is that whatever you do will change the structure in the parts and may leave them brittle. But at this point what have you got to lose?. Maybe someone else has a better idea.---Meltedmetal
Reply:Pictures please.......zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:thank you all.  i will try and get some meaningful pictures tonight and see if i can upload them decently.   i agree that i haven't ever gotten a real decent solution, i have welded the sickle head end straps before and i sometimes get them to hold, but mostly i end up crystallizing the dumb things and they break alongside the repair, then i give up and buy new ones.   i try not to break them if at all possible, so i have years between repairs and i forget what i tried and what did or didn't work, i got this set to do now and i have two sets that my brother (who is really hard on sickle mowers) gave me to repair, so maybe this time i will get it right.thank you all.  pics to follow tonight hopefully.micheal
Reply:Tried brazing?
Reply:If you have or can borrow a needle scaler, vee out each side of the cracks, heat both sides, weld it one pass w/ 6011, peen the hell out of the weld w/ the scaler, then finish welding it up and peen the weld and each side of the weld again until you can't see the ripples in the bead. This relieves the stress on each side of the weld.    Maybe someone else has a better technique.                                                           MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:We broke our share of pitman sticks years ago but I don't recall if we ever had to repair/replace the socket/strap pieces.  Way too long ago.I'm with G-son on brazing though.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:here are some pictures of the parts that i am referring too.  you guys think brazing will hold?   haven't tried that, i could definanely give that a whirl.   looks like if i weld, peening and slow cool seems to be a good technique?  after looking at the photos of the pieces, what do you think?thank you.
Reply:Considering the receipt in the picture you already know about Mcmaster Carr I would get 2 of these http://www.mcmaster.com/#shaft-collars/=taxqll in the appropriate size and replicate the rest out of steel flat bar weld the flat bar to the collar and away you go. Just a thought.
Reply:Did you try doing a spark test to determine steel type ? This may be of interest.
Reply:I have no idea where those are mounted, what they do, or how much space there is around them, your description is probably good enough for people familliar with the type of machine but I am not. Just saying, in case all this is completely unusable.Spontaneously, I'd braze them back together, and, if there's room, also braze something along them for reenforcement. Possibly two pieces of mild steel round bar along the edges, or a piece of thick sheet metal/flat bar on the flat side. I have been known to repair stuff just to see if it can be done, it might very well be better to make one from scratch as Big Worm suggested.
Reply:You could aslo make that piece out of metal, and for the I.D. where the pitman arm slider goes (circular hole) use a brass bushing. That way, it wears less on the other pieces, and makes the piece serviceable.
Reply:This is what his setup looks like on the flywheel end shown turned 90 degrees from installed orientation.  Hard wood pittman stick bolts between them.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:Braze them and be done with them, like every other farmer out there has done for the past 75 years!
Reply:i will be brazing the ones i have right now and buying enough to re-manufacture if they let go again.   thank you very much everyone for all the help.i appreciate it.micheal
Reply:From the photos, the break appears to be caused from bending forces.  In use, the primary force on the straps is tension and compression and should not cause this type of failure.  Is it possible the pitman stick compressed (in width) with use and the bolts have been tightened several times . . . possibly starting a crack at the bolt hole?  I'm with Duane, brazing is a good repair method for ferrous castings, but it doesn't have great tensile strength.  So Meltedmetal's suggestion of reinforcement sounds like a good idea to me.Dynasty 300DXSmith He/Ar gas mixerMM350PHobart Handler 120Smith LW7, MW5, AW1A
Reply:4sfed, yep, these straps were pristine untouched models until the main casting failed in a catastrophic failure and the whole support system for the dragbar let go and that caused these straps to fail and wreck a perfectly great set of straps, darn castings!   whole chaincase opened up and died.  that ended this mowers career until i have just now found parts to rebuild a great mower!  i gave up on brazing thinking it wouldn't have enough strenth but based on all the feedback i think i will give it a whirl and braze them w/ reinforcing steel in the right places and see what happens.   can't hurt, they are unusable they way they are, so if it works - great!   thanks all.micheal