MOPED ARMY

mopeds are made of a mixture of hardship, heartbreak and pure joy.

The frames are just made out of steel. not sure of the exact grade or anything but I just weld mild steel to them. Works like a charm.

I think what your friend is saying is that if they are made of different material (like copper or something crazy,) then it increases the rate of corrosion due to a reduction reaction. At least that's what i got out of my materials engineering class when i was able to stay awake.

The only time you need to worry is if you try to weld mild steel to something that is heat treatable, or a has a high carbon content. You'll get cracks in the heat affected zone due to thermal shock and hardening because of the carbon content. That's why it's called mild steel, low CC.

Use a MIG welder if at all possible, only because it's easier to get a nice bead.

However, I did see one of my freiends weld aluminum to steel once, by accident. It actually held until he started tapping on it after he inspected it and the weld looked terrible.