Hi,

I was just hacksawing a piece of wrought iron. I know it's not hard by carbon standards but it seemed very difficult to saw compared to mild steel. What's up with that?

Thanks,
Larry

First off there can lots more carbon in Wrought iron than is commonly believed... I have seen analyses showing upwards of 45 points of carbon... which puts it in the medium carbon range. Besides there is often much more silica in wrought iron than in most modern steels and where it is present in modern steels it is often added to increase abrasion resistance... which could be hard on hacksaw blades. So a given piece of wrought iron could indeed be very hard to cut... but another piece might cut easily.

the silica in wrought iron is present as ferro-silicate spicules rather than in the iron lattice like most modern alloys. So basically you are sawing though soft iron completely filled with glass fibers! This dulls saws *fast*. Hot cutting at welding heat is generally a better way.

*Old* bloomery wrought iron can have carbon contents ranging from zero to above 1%. Old smithing books discuss testing *every* piece of iron you buy to figure out what it is and what's it's good for.

As a boy, of no more than 7 years, ... and probably less, ... there was a variety of old farm machinery laying around the "Home Place".

I clearly remember applying my trusty hacksaw to a carriage bolt, ( in order to remove a board that I wanted for some reason ) on an old wagon.

Obviously, my experience, and point of reference were very limited, but to this day, ( 50 years hence ) I remember that it took more than 1 session with the hacksaw, to get the head off what was no bigger than a 5/16" or 3/8" bolt.

It was, a strange looking bolt, with a very distinct "grain" to it, ... that I ( much later ) came to know, was Wrought Iron.


Quite often, when I fume about how imprecise, and bothersome it is, to cut-off stock with chisels or hot-cuts, I'm reminded that the material the "Old Timers" used, was in several ways quite different from modern steel.


Not "Better", ... or "Worse", ... just different, ... but yes, sawing is definitely NOT the best method.for cutting Wrought Iron. :P


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Thanks.