OK, here is a link with the information you need:
http://www.owwm.org/viewtopic.php?f=77&t=92755&p=634309&hilit=van+norman+12#p634309
Pay attention to the PM links, as there is a very in-depth discussion of lubrication of the Van Norman #12. The problem with the discussion, as with most "expert" sites, is there are different opinions by the resident "experts," so if you are looking for a "pat" answer, good luck.
Also, when you hit 20 posts on here, the downloads area, American Milling Machines, has the #12 manual, instructions, brochures, and various other information. Some of it I scanned in myself because the quality of what I saw elsewhere left a lot to be desired.
One of the MOST knowledgeable guys about these mills is "Cal Haines" - he is a member here though doesn't visit much. Great guy- I owe him some parts I need to get to the post office to ship. Another VERY knowledgeable guy with a #12 who is no longer here (I wish he was) is Lane. Here is his site:
http://sites.google.com/site/machinistsite/TWO-BUDDIES/lanes-home.
I will be very blunt, if you are a newbie, some of the guys on the Yahoo Van Norman list tend to be pretty ornery, and not too helpful. A couple of us on here own the #12. I had 2, a 1943 Navy one I parted out, except for the base, ram and knee, and a 1946 I am bringing down my basement to strip, refinish and restore. I use two stripping agents that I personally favor. One is Citrustrip, and if you are working indoors, that is good stuff to use. Smells good, not too toxic, water soluable, yet it works. Then I have this graffitti remover they sell here in NYC, Schmeckenbecker's or something like that. It works really nice on grease and paint, lifts it right off. A few treatments by both of those brings you down to a stable base to paint on. Some people fill with auto body putty, bondo, or metal-filled epoxy (Devcon). This is especially true for the crack between the base and the column (I had to split mine up to get it down the basement stairs- see the post in the forum). But I'm going to mill with it, not submit it to the Smithsonian, so I am not going to fill. I will scotchbrite or wet sand the surface and paint it and that is it.
I used Rustoleum Smoke Gray on the 1943 one to practice, and, as you see from the photos on here, it came out nice- the before and after is pretty stunning. The Rustoleum takes a WEEK between coats to fully cure. The original color of these machines was a funny green color, like a forest green. While I like to reproduce faithfully sometimes, I wanted the gray, the green is just too ugly.
This should get you going, plus talking to Cal.
I would LOVE for you to post some pics of your restoration process on here...please?
Nelson