View Full Version : TIG Welding Castings

12-28-2005, 06:25 PM
I have been trying to get good cosmetic tig welds on the (aluminum) primary chain cover on my '52 Chief with no success. I had some small cracks welded up but when I mill the welds flat, I keep getting porosity over and over again. I have had it welded four times and have used two different welding sources. I have degreased the cover, run it though the diswasher, baked it in the oven, boiled it, but still have the same problem. Anybody got any clues?

Mike L
12-28-2005, 09:09 PM
Don't blame the welder. It's about impossible to weld these old casting without porosity. I usually end up just touching these pits with my mig welder one pit at a time and still may have to spot them more than once. Another way to help hide the pits is before you grind it to the level it needs to be, is peen it, to close up the pits then smooth it out. Even still don't expect to get it perfect. The impurities are endless in these old castings.

12-30-2005, 03:47 PM
I was considering the peening option. Perhaps have a bead laid down, mill it off to within .020" of the surface and then peen it. Worst aspect of this project is that the bad area is on the little appendage of the generator drive area--the most visible area on the cover. Thanks for the quick response.