The mills around London that produced barrel hoops were operating under a patent of c.1680 that also dealt with round and half round iron. However I suspect that it was not often made. First the bar was slit in a slitting mill and then passed through the rolls again to give it the desired section. I have seen a patent of c.1780 for the classic 19th century rolling mill, though the mill was in fact intended for rolling copper. Henry Cort applied this or something like it to iron in his 1784 patent (for puddling). However his process seems to have had a slow take up, perhaps because ironmasters did not wish to risk being asked to pay a royalty for the use of his process (though no one did pay one after 1790). The answer to your question is thus probably 'about 1800'. Nevertheless, (as indicated) there are complications.
Peter King
-----Original Message-----
From: Arch-Metals Group [mailto:[log in to unmask]]On Behalf Of [log in to unmask]
Sent: 10 May 2006 16:40
To: Peter King
Subject: Rolled Iron Roundstock
A metallurgist friend is giving a talk at a historical site and needs to
know when rolled round rod was generally available for sale.
Anyone have a good off the cuff idea?
Thanks
Thomas Powers
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