It doesn't apply in your case, but my grandfather used to repair iron Ridgid pipe wrenches. He was retired from Ridgid at their main plant in Elyria, Ohio, and they outsourced the repair of large pipe and nut wrenches used in the oil fields.
Many is the time when I was little (1950's) that I watched him grind the bevels, and braze a wrench. He used a large rosebud tip with the flame set so soft it waved around as he moved the torch, making a soft hiss that I can still recall.
He used to tell me they would sometimes get a wrench back for another break, but the braze repair held and the wrench broke in another spot.
I've wondered that myself, and I don't know. My guess is a moderately strong but moderately priced alloy that also forges easily; maybe 6061. If it's
2024 (possible) or 7075 (very unlikely), you can't weld it and produce a strong fix.
Aluminum alloy-testing kits tend to be expensive. But the tests for 2024 are simple; I forget what they are. What you're looking for is copper in the alloy. Any of the 2000-series are going to give you welding trouble unless you're very knowledgable.
The ASM published a book of simple tests that's supposed to be really good, but I've never seen it. You may find it in a university library: _Rapid Spot Testing of Metals, Alloys and Coatings_, by Andrew Holmes.
That's an interesting failure - in *normal* use that area of the wrench is in _compression_ & shear. Putting tension there, to get it to crack, would require using it backwards & I don't think that it's possible to use a pipe wrench backwards - I think that it would always release in that use. I suppose that it could have cracked from someone using it as a hammer, but *who* would do that?
You're not going to know the state of the repair until you are putting lots of torque on it. The only way I would trust it is to stress test it after welding. Ernie says use 4047 on cast aluminum. Try that or 4043. Test it with a long cheater before use.
Iggy in his own way, is one of the smartest people posting on these newsgroups.
He learns fast, knows when he doesnt know something and isnt afraid to ask questions..intelligent questions...nor does he claim to know everthing, unlike many posters do. Even questions that may make him look ignorant.
Ignorance can be cured, as he so aptly demonstrates
Stupid is for life...as others so aptly demonstrate so very often.
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.