Sorry if this is the wrong location for this post.  Im just starting out and my "anvil" right now is a small piece of railroad track.  There's not enough room to cut and grind a horn, so I'm trying to figure out an alternative.  One thought was to hammer down a round pipe (which I have plenty of) into a taper and fill it it with concrete.  Opinions?

Note: this will be for small projects only.

Why fill with concrete?  How big a radius does you projects need?  I have a bickern for small items---like arrowheads; cone mandrels for large items like trivets and made stake anvils for stuff in between---you will note that the RR spike driver sledge head could have been forged down into a tapering horn, but most of the small curling I do, I do on the flat anvil face with a light hammer. I also use bull pins when needed.

A friend has asked for a celtic armband.  She has made her whole ren faire outfit by hand so it doesn't need to look fancy but its a relatively large radius.  I figured filling it with concrete would add some heft, reduce vibration, and improve efficiency. (I used to have burly rock climber arms, but since having kiddos I am small and weak)

Concrete doesn't really add anything unless it's under your equipment and tool stands. For a one off use plywood for the jig, it doesn't have to last but one use.

I also dis-recommend  grinding rr rail too look like a London Pattern anvil, there are too many easy alternatives to a horn on an anvil. A solidly mounted leg vise is highly desirable in a shop at any rate and they hold many bicerns as opposed to just one on the anvil. Another good alternative is a "portable hole" a hardy hole on a stand independent of the anvil. These are highly desirable for more uses than any one person can list.

Frosty The Lucky. 

If it's just to bend hot metal around once use wood.

Bleu86

I am in Liberty Hill tx just a few miles north of you. I have some very hard steel that would make a good starter anvil. Most of the stuff in the picture is jack hammer  bits from large excavators. There is a local shop that lets me have the broken or worn out bits.

Pm me and I either give you some or help you get some from my source.

David

45 minutes ago, Bleu86 said:

A friend has asked for a celtic armband

May I suggest you make the armband out of copper.  A hammered copper armband can look quite lovely, and they chase quite easily, flat before being bent around a mandrel.  If you are going for a celtic knot theme, a jeweler's saw will cutout the openings between loops much more easily than in steel.  Just remember to anneal periodically as you work it.

Or braided copper wire then annealed and flattened.  Then annealed, buffed and formed around the arm.

One thing that often escapes people making round objects is that you don't have to bend around an object like a horn. 

You can use  a plate sitting on your rail to create a void over which you hammer, thus generating the bend.  If carefully arranged, you can coil the progress so you always have clearance to swing your hammer.

You might use that technique on a thickish piece of stock to make a sector of the radius to match your desired circle. For something as thin as an arm band you might be able to use it like a sheet-metal dolly.

Rockstar is right, anything that has an arch is your friend with bending. Cones are nice but really if you have 2 or 3 round metal objects you can tighten your work to your need. Arms are not cylindrical so dont get too particular on making it a perfect circle. xxxx my first anvil was... well i dont really know what it was supposed to be originally, but it has a 5 inch radius on it and it worked till i got a piece of RR that i only used to make bends over. RR has 2 radius' on it - top and side. Cones were a luxury

Copper would look really nice too all buffed up, and easily tweaks to her arm shape cold.