Putting a radius on an anvil edge

[Farmall]

Lately several people have been discussing the pros and cons of radiusing the edge of an anvil. Several folks piped up to say that they have put different radius-es along the edge. It got me to wondering.....what radius or radius-es did you put on your anvil and why? I was wondering what the most common radius-es used were. Appreciate any and all feedback.

[John B]

Start big near to bick, go to small towards heel, actual size of radii depends on anvil size and length of face 3/8" would be towards largest I use

[Randy]

You need to have a fairly sharp edge on your anvil except for about 2-1/2" from your cutting table back. The sharp edges should have the sharpness knocked off or no more than 1/32" radius.On the near and far side you want about a 3/16" radius close to the cutting table. See drawing. This is because you use the edges for cutting sholders into your ironwork with either an edge blow or an half faced blow. Half face blow is shown. If you want a sharp sholder in your work you use your sharp edge of the anvil. If you need a radius or a fillet you use the radiused edges. You do need to have both.

[Nakedanvil - Grant Sarver]

You're going to get a lot of different opinions here. Me? I never leave sharp corners on an anvil. Sharp corners cause no end of grief. Forge a sharp inside corner, do some more forging on the piece and nine times out of ten you go back to that corner and there's a crack. When you're flying around the anvil, doing this and doing that, you'll hang the piece over the edge to straighten it a little and sure as heck, you'll chew it up on that sharp corner. Happens to me when I'm working on someone else's anvil. The last anvil I dressed, I put a 1/2 inch radius in the far side and used it for drawing. On the very rare occasion that I need a sharp corner, I use a hardy block. On the rest of the anvil I put at least a 1/8" radius with one spot 1/4.

[Larry H]

you need a semi sharp edge......for instance what if you have to forge a ball ? there are many times after a few years of " learning your way around the anvil " you will wish you weren't so rash in your decision to grind the edges off. Keys are another example. Just "break " any edges that might leave cold shuts in your work, but how do you know ?...... learn your " way around the anvil " before you decide. You would be astounded how many things can be forged with just a hammer and anvil.....even shovels ! ! ! . ( but you have to radius the edge over the cutting block ). Work on it a few years before you decide.

[HWooldridge]

Yeah, this is a blondes or brunettes discussion (or redheads!). I have about a 1/2" radius on the far side near the horn that extends a couple of inches and gradually blends to about 1/16" radius down the edge toward the heel. The near side of the anvil starts in the same area about 3/8"r and blends the same way. The only fairly sharp edge is the narrow side next to the table but even that is slightly broken - like Grant said, truly sharp edges are bad in forgings (and other items such as moldings, castings, etc.)...has a tendency to create a notch effect.

[pkrankow]

I have broken edges that approximate 3/4 inch radius, very fat, and cause grief as well. I have very few areas that I can make a clean transition. Making a hardy tool with sharper edges is helpful indeed, but I sometimes wish for clean edges with a small radius. Eventually I will get the materials and equipment and skills together to properly repair this anvil and choose my own edge radii... or just replace it.

On my hardy tool having a sharp edge caused me to cut instead of forming the first time I used it. This was not entirely unexpected. I have not finished cleaning it up and choosing the edge radii.

Phil

[Nakedanvil - Grant Sarver]

On my hardy tool having a sharp edge caused me to cut instead of forming the first time I used it. This was not entirely unexpected. I have not finished cleaning it up and choosing the edge radii. Phil

What sort of "hardy tool"? I'm talking about a square block with different edges.

[Frank Turley]

B.I. (Before Internet). Yes, in the 'olden days,' who knew? When I would get ahold of old, used anvils in the 1960's and beyond, many of them would have maybe a 1/4" radius on the far side only, horn to left. They usually ran from the anvil step to nearly the middle of the waist. I wondered about that until I purchased one of my first how-to blacksmithing books, "The Blacksmith's Craft" out of London, England. On page 4, it showed a 1/8" radius on far and near face corners, from the anvil step for maybe 2" to 3" in length. I followed these instructions on all of my anvils, except I made the radii almost to the center of the anvil waist. I did no tapers of the radii. I kept them all at 1/8". Works or me. My 2¢.

When I was in horseshoeing school in the early 1960's, we got a new anvil into the school, and our teacher took the file side of a horse rasp, and put a tiny radius on all face edges. That was it.

[pkrankow]

What sort of "hardy tool"? I'm talking about a square block with different edges.

That about sums it up. I started making it when I made my hot cut, I upset a piece of 4140 round into the hardy. I later squared it up, and have not finished grinding it. The edges are rather sharp with no radius at all on them.

The only picture I have is the two pieces of round heating in my gas forge.

Phil

[pkrankow]

hmm....won't let me add a picture to an existing post...

As I said it is a bit rough, and I have not yet finished grinding to intent. Welding a cube on a shank would work easier if I had a welder available.

Phil

[Farmall]

I knew I was going to get a bunch of answers and I thank you all for offering them. I know that a sharp shoulder is a stress riser just wanting to crack, but I was curious to see how big a radius was used. So far, seems like 1/2" radius is the largest with most going 3/8" or less. If there are more replies to this thread, I'll compile them and post what the consensus seems to be.

[Jason @ MacTalis Ironworks]

Start at the horn, run approximately a 1/4" to nothing about 3" back. You need sharp edges for some things, rounded for others. Which radius you chose is determined by what you are making. For example, the animal heads that Brian Brazeal makes require good sharp edges. If you don't have them, you can upset a hex into your hardy hole and make a new edges tool, leaving opposite edges sharp, 1/16, and 1/8 radii.

[ThomasPowers]

Sharp edges leading to cold shuts seems to have been more of a problem back in the real wrought iron days and the books written back then tell you to round the edges of a new anvil.

Most of my old anvils come "pre-rounded" one might say. If I need a sharp edge I have a large block of steel I can use. Can't recall needing an edge sharper than a 1/8" radius though. On the other hand I might do stuff that way because I don't have a sharp edge on the Trenton, HB, PWs, A&H. The Fisher is the closest to a sharp edge; but so wide I'm more often in the middle of it!