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I broke a 3/8 extension bar while I was undoing a bolt. It broke into 2 pieces (2 blue lines) from the red line I drew in the following picture:

enter image description here

Is it possible to weld the 2 pieces together? Will it be strong enough for average use (below 50 nm torque)?

LFY MP7.3
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3 Answers3

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Yes , no. To properly weld and heat-treat to original properties would cost possibly 100 X the cost of a new extension.

blacksmith37
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Getting a new, factory-made extension bar (or other common and mass-manufactured piece of metal) is both

  • cheaper, easier and faster (unless you happen to be pretty much away from some trading point)
  • gets you a better and more reliable product (subject to caveats as well).

No matter how good welder you are, you can at most restore the instrument to its original strength that was not enough to begin with (otherwise it won't break).

Depending on your working habits and abilities, you may use the pieces to create some non-standard tool, but if you are into this, you won't ask the question in the first place.

fraxinus
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If you are a welder, yes. Chamfer both sides, and weld it. I'd say TiG weld it with 680 welding rod, tensile strength of 120,000 pounds per square inch. The welded area heat treats itself as its being welded. After grind off the excess weld and it'll be good as new. If you aren't a welder and would bring it to a welding shop, no. Cheaper and easier to buy a new one.

Wizbow
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