Ignoramus25707 wrote:
I have a bunch of street plate steel, that I want to magically
transform into welding tables.

They have rust on them, it is not horribly deep, but it needs to be
removed.

What is the most efficient way to do it using, say, a 9 inch angle
grinder. What abrasive things are best for it?

How large?

If you have the room and they will fit you could use an electrolytic
bath. I have one built from a water tank, Another one from a couple poly
drums. For you maybe something like the kiddy pools or the small
livestock tanks. They grab some PH+ chemical from a pool supply outfit (
soda ash, washing soda, sodium carbonate )

http://antique-engines.com/electrol.asp
http://www.instructables.com/id/Elec...val-aka-Magic/

You can basically make a tank out of anything that will hold water BUT
it cannot be metal unless you line it with something non-conductive.

I have done full car frames. You can do the interior using electrodes
with standoffs to keep them from grounding out. I used cheap foam.
Works great on things like motorcycle tanks as well.

--
Steve W.