Welding on the block
 

I got a 350 Chevy (i think so) that has paid it's debt to society. It had a hard life and definitely had a few visits to the machine shop. So I decided making a table out of it would be a good use for it instead of the crusher. My biggest problem is I tried to weld one of the pistons to the block and I can't seem to get a good weld on it. I would like to think of myself as a half decent welder. Just didn't penetrate like it should. Any suggestions on how to get a good weld on a project like this? I think I will play around with an old block of cast iron and a broken piston to see if I can figure out what I'm missing. The best combination I got was wire speed at 135 and 19 volts but I could still break that with my hands.

might need a high nickel content wire for cast iron and a 220v welder. my shop uses a 120v unit and it can;t penetrate anything thick.

Cast iron would require nickle.