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Wire can be interesting. I am thinking of the square wires the thickness of about 30 microns- 40 microns across and 60 mm long of composition 91%Gold 9% silver dated to 325BC....from the La Tolita region of Ecuador. these are not twisted or folded or probably not drawn...so how were these gold wires made? On Thu, Dec 30, 2021 at 10:23 AM king peter < [log in to unmask]> wrote: > My expertise is on iron rather than copper or brass. My understanding is > that the use of rolling in wiremaking goes back to John Purnell's patent of > 1766. Brass wire was made before that at Bristol by the Bristol brass wire > company. > > Iron wire was made at Tintern from about 1567. The process involved > forging rods, using straining hammers, which seem to have been tilt > hammers, before the product was drawn using drawplates. This was > technology introduced from Germany, probably Nuremburg. > > Slitting mills producing rods for nailmaking were invented in the Liege > region about 1580 and introduced to England in 1590 (Dartford in Kent). > That on Cannock Chase in Staffordshire existed by 1611, followed by Hyde > Mill in Kinver (also Staffs) in 1627 and then various others. I am not > aware of them being used to provide wire rods, but I may be wrong. > > It set this out to provide a historical framework. I am not qualified to > say what marks the various processes would leave in the metal. > > Peter King > > On 30 December 2021 at 06:09 Dawn Hoffmann <[log in to unmask]> > wrote: > > also see: https://link.springer.com/content/pdf/10.1007%2FBF03215438.pdf > > On Thu, Dec 30, 2021 at 1:06 AM Dawn Hoffmann < [log in to unmask]> > wrote: > > Hello, > For what it is worth, you might be interested in this image: > https://www.nuernberger-hausbuecher.de/75-Amb-2-317-40-v > > I have read somewhere that rolling mills in the 16th c were for finishing > already formed sheets of metal to smooth it out (surfacing only) because > the pressure needed for the reduction of material was not sufficient (that > part of technology still needed tweaking..). (I am not sure if I wrote > notes on where I read that.) Rolling mills for reduction were not in much > use until 18th c. as far as I know. There was some use of rolling mills in > the Renaissance, but not widespread use. I am still looking for more > history of these processes too. Rolling of flat sheet and wire are often > on the same rollers with "v" grooves in the rollers. But for true corners > you need a drawplate (and lots of annealing!). > > I do not know if this is what you need to know.. > SIncerely, > Dawn > > ps. sorry to say - stay away from cheap drawplates - you waste a lot of > time and effort on badly made tools.. > > On Wed, Dec 29, 2021 at 8:18 PM Robert Gordon < [log in to unmask]> > wrote: > > Dear David: > > My first guess is that it was made in a slitting mill. There was one in > operation at Tintern in England in 1567 but that may have been a copy of an > earlier one in Belgium. The surface markings and the flash at the edges > suggest shearing, not rolling. It certainly was not drawn and the sharp > edges suggest that it was not passed through grooved rollers. > > Thanks for your family news. I have to report that Carol has a case of > Alzheimer's and is in a care home. My mobility isn't what I'd like it to > be. You may have seen my latest paper, in the current *Historical > Metallurgy. *I have one in review in *Arms & Armour* on welded cannon > made by additive assembly of discs welded together in a hydraulic press in > 1845. To my surprise the complex processed worked and the cannon proved far > superior to cast ones. > > Best wishes, > > Bob > On 12/29/2021 12:19 PM, Killick, David J - (killick) wrote: > > Thanks very much to Tobias Skowronek for replying to my earlier query > about chemical and lead isotopic data for metals in Portuguese and other > shipwrecks. I highly recommend his PhD thesis (2021) on this topic. > > > > I have a related query. There is a rich cemetery in the Zambezi valley – > on the border between Zambia and Zimbabwe – called Ingombe Ilede, excavated > in 1960 and 1961, and published in 1969 by Brain Fagan. The graves contain > ivory, gold, X-shaped copper ingots, lots of Indian glass beads, cloth > (preserved by contact with the copper), iron wire-drawing plates, and lots > of copper and bronze wire in various gauges. The older radiocarbon dates > are a mess, but two new dates on cloth both calibrate (using the SHCAL 20 > curve) to the interval 1470 to 1640 AD at 95% probability. Prior to 1531, > when the Portuguese founded their first trading post in the Zambezi valley, > all imports from outside the continent were from India, China and the > Islamic world, carried into the African interior by Swahili merchants from > their ports in present Kenya and Tanzania. Thereafter, imports could be > from these sources, or could be European. > > > > We are trying to decide whether the cemetery at Ingombe Ilede falls before > or after 1531. Jay Stephens has done lead isotopes and chemistry on 15 > pieces. Two copper crosses are from the Kipushi mine in Katanga, about 500 > km away, but the non-radiogenic lead isotope ratios obtained for the bronze > wire are difficult to interpret, being compatible with Africa, European, > Near Eastern and Indian sources. Close inspection of the coarsest bronze > wire has however convinced me that it was rolled, not drawn. It has > absolutely regular square section, about 3.5 mm on a side, and is in > lengths up to 1.3 m. > > > > What can the Arch-Metals hive mind tell me about the early history of > rolling metals in Europe? (I have not yet found any mention of the rolling > of metals in the Islamic world, India or China before 1800). My searching > to date has turned up the 1480 conceptual sketch by Leonardo da Vinci of a > machine for rolling lead cames for windows, but no evidence for the actual > use of a rolling mill until the 1590’s, and that for rolling and splitting > iron plate. Do you know of any evidence for the rolling of copper rod or > wire before the latter date? > > > > ------------------------------ > > To unsubscribe from the ARCH-METALS list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=ARCH-METALS&A=1 > > -- > sent from Thunderbird > > > ------------------------------ > > To unsubscribe from the ARCH-METALS list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=ARCH-METALS&A=1 > > > ------------------------------ > > To unsubscribe from the ARCH-METALS list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=ARCH-METALS&A=1 > > > ------------------------------ > > To unsubscribe from the ARCH-METALS list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=ARCH-METALS&A=1 > ######################################################################## To unsubscribe from the ARCH-METALS list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=ARCH-METALS&A=1 This message was issued to members of www.jiscmail.ac.uk/ARCH-METALS, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/