Sit it out in the rain for a hundred years, then look at the rust. If
it's fibrous (looks a bit like weathered timber), then you've found
your wrought iron. If you're near a port city, there'll be an old
anchor or something up on a plinth somewhere. A look at that will
usually show you what it looks like.
Another way is to find any ferrous construction (maybe a bridge) from
before the age of cheap Bessemer steel. This will be made of cast iron
and wrought iron. Cast iron is strong in compression and easily shaped
into complex solids, wrought iron is strong in tension and formed by
forging. Looking at the shape of bridge components on an old bridge,
or where they'd have their forces applied, then you'll be able to see
which is which quite easily.
For some reason I can just see someone out with a hacksaw cutting
some of the tension members off of an old bridge that is still in use.
I think I've seen too many episodes of The Red Green Show ;o)
lol...I feel your pain more than you'd think! This past summer, just
finished up the restoration work on a Whipple bow string arch Erie Canal
change bridge - in fact one of the only ones left with cast tubular
compression members. The lower (tension) chords are the original
wrought iron and yeah, the stuff is kind of priceless. I did a bunch of
the welding/forging repairs and helped out with assembly and final lift.
If you want to take a peek, check out:
scroll to the bottom of the page to see the bridge. It's an old cutie.
Toughest part of the project was finding the danged stones for the
To all who have served or are serving the cause of freedom, from
whatever country, whether in peace or in war, at home or abroad, thank you.
Wrought iron is markedly softer than any modern steel. Including the
now rare 1020. You can probably tell by cutting it with your favorite
jack knife. After trying your knife on some modern steel like a
common angle or channel. (A36).
If it marks easier ... its probably wrought.
May be a bit hard on your knife edge :)
1018 is readily available. Buy it at any steel supplier or machine
Wrought iron has a lot of magic connected to it. Many "blacksmiths"
love the "bugity bugity". The more the better. Truth is working with
wrought iron is a major pain in the ass. Get some and try the stringy
crap. Give me A36 or 1018 any day.
Wrought iron is a funny thing. The earlier the manufacturing date
of the raw material the more likely you are to find material that is
troublesome to work with. That's because of the lack of control in it's
manufacture. With sulphur, phosphorous and slag percentages varying
enough to make some hot short and some cold short. But by the early
20th century these bugs were worked out here in Pittsburgh by the
A.M.Beyers co. Their product was sublime. I would trade every ounce of
mild steel for a chance to have a couple of tons to work with. Alas,
the only known supply of this stuff became rebar for a furnace floor 20
years ago. Some 10 tons or so of 3/4" square.
I used to have a book "Wrought Iron" about the Beyers Co. and their
process. If my memory is working today I think they actually "mixed in"
the silaceous fibers that are found in "traditional" wrought iron. This
would end up being a product very much like the Pure Iron that has been
around (now gone) the last few years. I have not tried pure iron but
have heard both good and bad about it. I guess it would be easy to work
without the bothersome splitting when forging at lower than welding
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