How to make a flat face for an anvil?

[4xdblack]

I found this nice big chunk of steel, and seeing it I thought about the possibility of using it as an anvil. It would be better than anything I've currently got. The problem I'm experiencing is that the face of this piece of steel is not flat. In fact it is very rounded. Not rounded enough to use as a horn, but too round to use as an anvil.

So, the question is... How can I flatten it?

I'm already aware of hand-scraping, and using a backing pad disk on an angle grinder.. But are there any other methods? Perhaps a way to maybe forge it flat?

The reason I ask is because I don't have the tools to do hand scraping, and I've already gone to the hardware store 3 times trying to get a stupid backing pad to work (you'd think there would be a guide on it... there isn't...).. So now I'd like to explore the possibility of some other options. 

So what can I do to flatten a piece of steel so that I can use it as an anvil?

Thanks!

[Tubalcain2]

can we have a pic of the piece? that would help a lot.

[Glenn]

How out of flat are you talking about, We need some measurements or something on which to base our answers.

[ThomasPowers]

I can use a 6" diameter cylinder of steel on it's side as a very nice anvil. What is it that you 1 have and 2 want to do with it that you can't?

The better ways of flattening a large piece of steel often involve milling or other machine work and so are usually many times more expensive than buying a flat piece of scrap steel---my local scrapyard has some 80# rectangular chunks of steel for US$16; you can't even buy abrasives to surface a curved piece for that!

[ThomasPowers]

It helps that my local scrapyard hauls their steel 3 hours south to a foundry by truck and so they are pretty happy to sell it to me locally for cash at the same rate they get from the foundry....