Here's a project that I worked on last night. It's a cast aluminum inner primary cover for a '70s Harley that I'm building. This part is 30 years old, and for those unfamiliar with bikes, this houses the chain and clutch, linking the engine and tranny together. The previous owner tried to pry the parts apart with a crowbarcausing cracks. In addition, there's a spot where the kickstand bounces against what's supposed to be a rubber bumper, whish is usually missing. The other spots are where the chain from the tranny to the rear wheel rubs. This happens when the chain is allowed to run for too long without being adjusted, aggravated by running a bigger front sprocket for lower highway engine speed. In other words, this thing has seen bettter days. This part is still available new for about $360.00. but I decided to give it a go. There's a LOT of info and some pics, so it will be in multiple posts as I complete the project.
These were pushed out from the inside, so I pounded them back in to get the assembly into better alignment then welded, ground down, and re-welded to get rid if defects. Notice how in the bottom pic the welds look better. Basically I started by running an arc across the areas to be welded to get the cleaning action to work, then went in with my filler. I tried both 5356 and A356 (3/32), both worked well, but at $30.00/lb, I'll be saving the A356 for where it's absolutely necessary. I used 3/32 Thoriated, Approx 175 amps on the pedal, and 17cfh argon.