Wrought Iron railing book

It depends on what you mean.

Hand built from scratch railings take a lot of skill and effort.

Anybody can build railings from components.

Check out

What do you regard as "wrought iron railings" ?

There's a wide range from bolting together components, to welding up standard bar and tube stock, through to "artist smithing"

If you're interested in the artist end of things, then I suggest a course. I was lucky enough to take a weekend course with Pter Parkinson this year. I made this

He's also the author of one of the few good art-smithing books out there "The Artist Blacksmith: Design and Techniques"

Dona Z. Meilach also has a couple of good books out there "Decorative and Sculptural Ironwork: Tools, Techniques, Inspiration"

and "The Contemporary Blacksmith"

You'll find ABANA or BABA the relevant associations for artist blacksmiths and their magazines are good reading. There's also an alt.crafts.blacksmithing usenet group.

What I am planning on doing is using some factory components with some handformed and CNC plasma cut details. I would like to see some info on planning and designing railing. I also need info on forming bends in handrail caps although I have seen some techniques such as splitting the handrail bending the two pieces separately and joining them back together. I learned long ago that blazing a new path is a hard way to learn things people learned long ago. Thanks for your help.