I've been using plain old Minwax finishing wax on the metal surfaces for a long time. Granted, oil will slowly take off the wax, but I simply reapply it a couple of times per year. Not a big deal. Ways are coated in way oil, but the table saw top, mill table, drill press table and column, lathe chucks, and the unpainted areas of the 'table' on the Keller saw all get an occasional wax coating. I rub it on, coating the surface completely, then leave it sit for a while to allow the solvents to evaporate. Then I go back and wipe off the excess. I only do this with the garage door open, as exposure to the solvent fumes can have adverse effects on your nervous system.
I read somewhere that a good wax coating can be made from bees wax and mineral oil. Applied the same way as paste wax or chrome polish. Pour some mineral oil into a pan and warm it gently on the stove. Using a double boiler might not be a bad idea here to keep from overheating things. Then add bees wax in small pieces totalling 1/4 to 1/3 the volume of the oil. Mix thoroughly and pour into a can that you can seal up and allow it to cool. Use the same was as any paste wax.