backhoe bucket repair

I'm working on my father-in-law's mini-backhoe bucket. It is old and has a lot of issues. What I was working on today was the fact that the toothbar (high carbon steel) was partly ripped loose at one end. I was able to pull it back in using a big comealong, and I welded one end using 7018, but as soon as I even started to loosen the comealong the weld broke like glass. I got some high-tensile stainless maintenance rod, pulled it back in and welded back up, and so far it's holding. The welding engineer from the company that made the electrode said to lay the stringer beads in with no preheat whatever, as the toothbar steel is clearly crack-prone and preheating it would make it worse.

One of the tooth shanks (also high carbon steel) has been missing its tooth for long enough for the shank itself to have worn down to a nub. Normally I'd remove this shank by using a flushing tip on an oxyacetylene torch, but after seeing how crack-prone the high-carbon steel is (Ernie thinks it might be T1) I'm very leery of using that much heat. I don't own an arc-gouging gun and it's too much work to grind it out. How would you guys go about removing this shank nub?

Grant Erwin Kirkland, Washington

Reply to
Grant Erwin
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Grant - arc-gouging gun ? - Plasma Torch with gouging nose.

I suspect the steel might be higher than T1 but that is about 360 BHN

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T1 is a good shot. This metal has a unique combo cocktail of heavy metals.


Mart> I'm working on my father-in-law's mini-backhoe bucket. It is old and has

Reply to
Martin H. Eastburn

We mfg. and repair buckets, some very large, the bottom leading edge is usually always AR plate along with the forward edges on the sides and the wear strips on the bottom. The lugs on top weather quick change or pin on are usually T1 and the rest is usually A36. We use all dual sheild from 1/16 to 3/16 and it is not uncomon to be running 350 to over

500 amps, no verts or overhead here! Run it in hot. I can not remember the alloy of wire but it is nothing special, I know its flux core and not metal core, I'll look at work tomorrow, good luck
Reply to
Jon Petrzelka

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