Originally Posted by Triticum Agricolam
Thanks everyone for your feedback. I'm really hoping to avoid using any splices on this, that's why I want to try to weld them. I'm planning in replacing the knife sections anyway so after I weld the break together I'll probably flip the bar around so where it broke will be on the right hand side of the header. Should be a lot less force put on it there.
I was hoping someone else would post this described method because it takes a fair bit of writing to explain it.
With this method you do need another piece of knife bar stock because you will need to also do the same weld procedure on the outer end of the knife to keep the knife the same length.
Rather than weld a straight break through a rivet hole, sacrifice some knife length and cut it on a long diagonal between two rivet holes directly under a section. This generally means a hacksaw cut just under two inches long. Once one piece has been cut off next to the break, use a knife section and some bolts to align the other parts properly to scribe the matching angle to be cut on the other knife segment that is is to be welded. Chamfer the pieces to less than half depth that are to be welded and then bolt it together straight using a section to bridge the weld joint. Once it’s tacked or welded on one side get the section out of the way to finish up.
I like to use a 1/8” 6011 on ac current set at about 90 amps using a start stop method as required, but that’s just me. You can hammer the weld a bit while it’s hot on a railroad iron if you are working on the floor, but don’t over do it. Tidy things up a bit with an angle grinder and bolt the section over the diagonally welded joint.
Now cut the outside end off and do the same weld procedure to get the proper knife length back using your extra knife stock.
I’ve repaired dozens of knives this way over the years, it will not break at or near the weld and the time spent is well worth the long term satisfaction.