Welding help needed

[ronko]

thanks all
Well, she's stuck back on there! Good, bad or indifferent!
Got it wrapped in an asbestos blanket till tomorrow.
Went and borrowed an IR Thermo. and bought some 7018.
Practiced yesterday with the 7018 on sticking the two 1/2 in. blades back to themselves. Today with my son's help with the torch, we preheated, kept warm between passes, and stuck the knife assy back to the IBeam. Yes; with preheating it was much easier to drop the vertical base metal into the puddle and had to make an extra pass because of it. Tried jacking, but couldn't really safely get it to a 45 degree. Probably not as pretty or scientific as you like but should have much greater chances of success than the first time. I'm getting pretty good as a grinder, mebbe some day I'll get better as a weldor.

 

[Pennsylvania Weldor]

One more input. The area that failed is called the "Heat Affected Zone". That's the area adjacent to a weld that is most likely affected by the welding heat, thus changing it's makeup. Temperature at the arc can reach up to 12,000 degrees F. The grader blade you welded is heat treated (hardened) throughout the entire thickness of the metal. Welding altered that area, and thus it failed.
Preheating was the way to go, "Lo-Hi" (low hydrogen rods - low moisture content in the flux coating) rods were also the way to go. 7018 or even stronger rods like the 8018, 9018, 10018 could have been used also.
Slow cooling like you did was good also. Hope it holds up now. Happy splitting (logs that is).

 

[bjcsc]

I'm getting pretty good as a grinder, mebbe some day I'll get better as a weldor.

That's how it works - in that order!