I found that the key to all of the methods of removal was that tapping, not 
beating, banging or smashing, but tapping, causes the joint to move. The 
joint moves and opens paths for the mix of light and heavy oil to be drawn 
into the gap. The oil fills the gap and lubricates the materials allowing 
them to move.

So what do I do?
1.    Mechanically remove dirt and loose corrosion from the surface.
2.    Apply a mix of light and heavy oil to be drawn into the gap.
3.    Tap the components with a small hammer.
4.    Wait.
5.    Repeat.

There are still problems that can occur:

Cracks propagated from rust pits can cause flakes to break free from the 
surface and wedge between the components. End result no movement.
Over time two steel components will weld together from just being in 
contact. End result no movement. Heat will greatly accelerate the process.
Bends, wrinkles, riveting, swaging, and misalignment can force items into 
shapes that interlock. Again no movement.
Galling caused by friction between two components will spot weld flakes and 
chips from one component onto the other. See welding above.

For the longer version go to 
http://dnighswander.blogspot.com/2012/06/winning-against-rust.html

These are my methods. YMMV.

Dave N.
aka Old Sneelock
dnighswander.blogspot.com 

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