Repaired motorcycle crankcase cover

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A customer had a broken honda motorcycle crankcase cover that was some kind of die-cast looking aluminum alloy.  Not much ductility in this alloy, as it had fractured into many pieces.I was concerned it was zinc-laden pot metal, but test weld showed no zinc burning, and file test showed it was soft like regular aluminum.  I welded it up with 4043 filler rod.  I advised the customer on an initial visit how to prep the piece for welding, and sent him off with a scrap of 3/16" thick 6061, which he trimmed and nicely formed into a patch piece to replace the many fractured pieces.  I welded inside and out and got full penetration.  Seemed to go smoothly.Customer is an auto body / paint guy, and plans to smooth it out and match the paint to make it look as if it were never damaged in the first place.Got a little stinky at the end there (oils were off-gassing from the heat...)
Reply:Great looking repair, I'm sure your customer can sand/buff the outside of that cover so it looks like new."The reason we are here is that we are not all there"SA 200Idealarc TM 300 300MM 200MM 25130a SpoolgunPrecision Tig 375Invertec V350 ProSC-32 CS 12 Wire FeederOxweld/Purox O/AArcAirHypertherm Powermax 85LN25
Reply:Nice, I've repaired quite a lot of motorcycle casings and Mr Honda's are real nice to weld
Reply:Great job!!And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:Thanks, I was really concerned it was pot metal and going to melt into a big blob right on the table, but actually welded up really nice.  The oil offgassing fumes were getting pretty bad at the end there, I remember it was just "steaming on the table" at the end there and stunk really bad.  But, the oils did seem adequately removed/prepped clean in the areas I needed to fuse the metals together, and veeing the weld joints helped a great deal.  (There was just one small "oiled crack" crack that was not vee'ed out... I had to take a second pass over that one to melt out the oil and metal all the way down to the bottom.)
Reply:You may want to consider having the gasket surface scraped by a machine shop.  It would definitely make it easier on you during reassembly.  I'd do it for next to nothing if you were local.
Reply:Nice, I like how you jigged it up prior to welding. Helps keep it in alignment while you weld.  MIG or TIG??
Reply:GTAW for sure
Reply:Fegenbush - thanks!  I wish I knew a local machinist who could do small jobs like you offered without a lot of hassle.  At times there are small things I would like faced or turned on a lathe, or parts like manifolds, etc surfaced flat after I weld them.  You not in the greater seattle area, by chance? Diesel - It was indeed TIG welded; using an Everlast Super200P.  And yeah the customer did a good job of jigging it up, with the wood brace pretty much holding the perfect position for the first couple tack welds.  (Not much good leaving it attached after that though, heat of nearby fusion welding would have converted it into charcoal.)