I was thinking of buying a cast iron (ASO) from harbor freight. And was thinking of then taking it to a welding or mechanist show and having it ground down and/or a tool steel plate added to it. is that a good idea or economical.

The general opinion is that any anvil is better than no anvil, and it is better to make do with a big hunk of something while you save your money for a real anvil. Contact your local blacksmithing group. They will help you find a real anvil at a reasonable price.

What Glen said first of all.

To answer your question. Sure, you can do all kinds of things to put a decent face on a cast iron ASO, virtually all of them will cost you as much as a decent anvil will if you don't get in a hurry. I don't think any of them will work nearly as well as a real anvil.

So, I repeat. . . What Glen said.

Frosty

Let me rephrase "I want to spend a lot of time and money trying to make a silk purse out of a sow's ear. Is this a good idea or an economical idea?"

In general if you factor in the time, effort, consumables of trying to redo a cast iron ASO you find out that you could have mowed lawns and bought a very nice anvil with a lot less hassle.

If you really want to build an anvil don't use cast iron as the base, use steel---LOTS easier to weld and heat treat with and as a source of a good sized hunk---try to find a forklift repair place and get a damaged forklift tine---the larger the better. It's a good steel to start with and can be found in heavy cross sections. A good knifemaking anvil can be made by just standing a section up in a bucket of concrete.

"you can put a lot of lace on a hog, but it's still a hog" There is a thread somewhere on heat treating a 110# HF ASO, saw it a long time ago. Just get the anvil you can afford, until you can afford the anvil you want or need.....

Silk purse... sow's ear, you know what I'm driving at. Glen, Frosty and Thomas said it best.
Another option, look in the phone book or google a large fab shop, call them and see if they have a big chunk of steel they will sell for scrap price. I have found a few 4X4 about a foot long over the years... for free, they would make a nice starter anvil.
I picked up a chunk of 4140 round for about $80.00. It waighed about 180 pounds!

I don't want to jip harbor frieght out of a sale, but I think you can do far better elsewhere.

Many of the used anvils I have seen for sale are 100 years old or more. The original owner used the anvil in order to earn a living and took good care of the anvil knowing that the anvil fed his family. Fewer blacksmiths today support their family only by blacksmithing, but have day jobs that pay the bills.

If you just need something to beat on, visit the steel yard or scrap yard and pay scrap prices. Most any metal object with a mass of 100 pounds will do. The real anvil should be looked at as an investment, both as a good tool and one that most likely you will not wear out in your lifetime.

If you can afford to do all that you can find a good anvil in your budget. Ten years ago I bought a 170# hay budden $150 a 120 # trenton broken at the waist $50 welded it together for about $40 & anice 140# no name for $45 I sold them all 4years ago and had enough money to buy a new Tom Clark. Spend your money on the best real anvil you can afford. You will not regret it.

Instructions for Fixing Anvil Shaped Object hence referred to as ASO

Step One: Remove ASO from stand
Step Two: Find a real anvil
Step Three: Place real anvil on stand
Step Four: Apply hot iron and hit iron repeatedly ;-)

Unicorn,
Sometimes we overlook the obvious. Great comment !!

Save your money until you can afford to buy quality tools and equipment. Remember that the cheapest thing you can buy is often the most expensive thing you can own. It is not cost effective to put a 4 story addition on a pup tent. If you want to buy a HF anvil, do so and use it until you can afford a better one but don't put a bunch of money into it. My first anvil was a 75 lb cast iron one that just said Mexico on the side. It worked ok until I was able to find a good anvil. I think I paid $65 for it. It is now on loan to a young guy just starting out. I am sure it will serve him well while he learns and until he finds a good anvil. Then, who knows, maybe someone has a large boat and needs an anchor.

I think all of my anvil troubles are going to be over soon. I was told the other day that a friend of the family's mother in law has a large anvil. That I may be able to get for little or hopefully nothing. If I find out any details on it I will post them. And just keep using my rail plate.