Low temp aluminum welding

I'm going to try a few different things and see how it goes. I've accumulated some housings I can't even give away so they are good candidates for me to experiment on.

I have a tig welder and gave it a really good shot at learning on my own. But it went off course and just couldn't get the stack of dimes look. I don't have the time to take a class. In my area they are only offered during week nights and I already get up at 4 am for work and home at 6 pm.

I've heard from welders that trying to weld a housing that has been soaked in oil is very problematic. The oil keeps coming out of the material and makes for a bad weld. I'm wondering if it will be the same with the low temp rod.

Just found this. Pretty amazing.

 
I recently broke the cast aluminum lever on the fence on my 1948 table saw (dropped it). I used an aluminum brazing rod to put the two pieces back together. It isn't showing any sign of weakening in use. You have to give it a tug to unlock the fence. I wouldn't have been comfortable using the MIG spool gun to try the repair.
 
I believe the rods are mostly tin plus a bit of silver....and of course secret ingredients..........however ,if you subsequently need to re do the repair,the filler is poison to TIG deposit...........the repairs are not resistant to corrosion either ,having dissimilar metals.
 
Yep, it's a tin filler rod. I have had very poor success with low temp aluminum trying to repair cast automotive components. The typical failure I encounter is a broken bolt ear, whether on a carburetor, a transmission housing, or a small engine control component. Every repair I have made of that type with low temp has broken immediately, and I end up doing the repair with JB Weld. I put JB on a carburetor mounting flange and it held for almost 20 years (could still be holding, but I sold the truck). Maybe probably I have been doing something wrong in the low-temp process, but I avoid it like taxes if at all possible.
 
I have used it for repairing and building up a broken off (and missing) part on a BMW motorcycle gearbox. I was able to fill the void left by the broken bit and build up sufficient material to then mill, drill and tap the new section. After that I bead blasted it and it was invisible and perfectly functional. Now, after maybe 12 years, the difference in colour is quite visible again but it's still together.
It is a brazing process, not welding! I have pulled them up on false advertising and misleading the ignorant - but never even got a reply...
The filler material is more brittle than cast aluminium but not as strong. So be careful.
Since the process does not use flux, I made sure I removed all aluminium oxide from the brazing area and meticulously cleaned the rods and the surfaces with acetone - just as you would for a high quality TIG weld. I've used it a few times since - always successful with the preparation described.
I would NEVER use on a structural aluminium fabrication though.
 
I bought some HF rods and am going to try them when I find the time. (on mandatory overtime now)

I figured I'd start with low cost rods and get some experience with them before moving up to the more expensive ones.

I have a new transmission modification I'm working on and being able to "weld" it makes it doable. Otherwise I'd not be able to modify it.
 
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I never had any luck with these type of rods. Of course what I was trying to repair was fairly large and I could never seem to get the temp of the surrounding areas hot enough. Possibly on fairly small items they work.
 
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