Fixed broken transmission mount

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Purchased a motor + trans to swap into my e30. The previous owner combined delrin trans mounts with oem rubber motor mounts. This caused one of the mounting ears on the transmission to snap off. Break was pretty clean. Used some carb cleaner and wire brush to clean the oil/grease/crap off the weld area. Tacked the piece on. Ground out the crack top bottom and sides with a carbide burr. Welded the top bottom and sides with 4043 at 180ish amps. Going to use oem rubber mounts this time around hopefully it holds up. Sorry some of the pics are crap was trying to use my phone while wearing gloves. Please forgive the terrible china tig working on a tight budget here. I ground it out another mm or so after this pic, it didn't seem deep enough at first.
Reply:bottomContamination DoneIf i did it again I would have cleaned it slightly better but it turned out pretty well for 20 year old cast soaked in transmission oil and road grime.p.s. this is a getrag 240 from a m42 mating it to a m50 bmw 6 cyl.
Reply:Usually, when I do aluminum castings, I weld them once, grind the weld out, and weld them again.  No matter how much you clean there will always be oil left behind.  The first weld brings all of the oil to the surface so you can grind it out and the second weld makes it look pretty.
Reply:I think it came out just fine.  I would have been tempted to extend the buttresses out just past the repair to eliminate stress on the weld, but probably not necessary if you get the rubber cushions installed evenly.Miller Syncrowave 350Millermatic 252/ 30A spoolgunMiller Bobcat 225g w/ 3545 spoolgunLincoln PowerArc4000Lincoln 175 Mig  Lincoln 135 Mig Everlast 250EX TigCentury ac/dc 230 amp stickVictor O/AHypertherm 1000 plasma
Reply:Thanks for tips, that makes sense. I could see crap floating to the top on the front edge of the pool. Maybe i will go back and grind them out the trans is still just sitting on the desk, not going in the car anytime soon.
Reply:Doing a full pen repair on highly stressed or even lesser stressedAL castings produces the strongest repair possible. The mountingtab on that trans is a high stressed part.It takes some more time, which I guess--from having to repair othershops "repairs"--where either little or no grooving was done is justplain ignorance, poor workmanship or both.1-Cleaning--with any brakecleaner solvent and leaving any residueto fume off from welding produces phosgene gas--which readily, permanentlycooks the lungs. There's a sticky about this on this site.-4043 is a basically compatible alloy for AL castings-Heavy beads on the sides, tacks on the top and bottom-groove 1/2 way or more into either top or bottom, then weld up-back groove from the other side into the root of the first weld and weld up-v-out the two sides--thru the temporary welds, then weld outhttp://weldingweb.com/attachment.php...1&d=1331927112 Attached ImagesLast edited by dave powelson; 03-16-2012 at 03:49 PM.Reason: additionBlackbird
Reply:thanks for the tips! I did v it out more than in that picture  but definitely not as much as I should have based on what you said. Do you think its worth it at this point to cut everything out and go at it again? With the brake clean I did fully let it evaporate before welding I do know about the dangers of fumes/residue. I normally prefer to use acetone for cleaning AL but the pressure from the aerosol greatly helped in getting the crud off this area. Also I'm far from an expert so I appreciate the comments. Im just someone with a crappy ebay tig tinkering around in my garage to try to save some money and have fun.
Reply:Originally Posted by dave powelson...any brakecleaner solvent and leaving any residueto fume off from welding produces phosgene gas--which readily, permanentlycooks the lungs.
Reply:It is the chlorine that gets you.
Reply:Originally Posted by AquafireBreathing most things in the shop won't do you any good, but I thought phosgene only resulted from heating brake cleaners containing trichloroethylene (TCE)?