A Process of Trial and Error
- experiarchaeuwm
- Sep 24, 2020
- 4 min read
Hello friends!
Socially-distanced blacksmithing is a phrase we never thought we'd need to write, but here we are. Despite the continuing COVID-19 pandemic, we've managed to have two forging sessions so far to work on spear 2.0, one in mid-July and one last weekend (9/19/2020). As of now, our second version of the spear is still unfinished, but we thought it would be a good idea to provide some project updates as well as some reflections on the process of experimental archaeology.
In mid-July, we met at StormCloak Forge (http://stormcloak.com) to begin work on the second version of the spear. All of us wore our masks and were careful to stay 6 feet apart from each other whenever possible. Back in March (which really seems like an eternity ago!) we'd decided to use pieces of wrought iron to forge the second version of the spear, since this is closer to the materials the ancient Celts of Iron Age Europe would have used. In fact, one of the MakerSpace blacksmiths had salvaged some pieces of historic wrought iron fencing from an abandoned property near "Eagle's Nest," the New York Long Island estate of William Vanderbilt II (1878-1944); "Eagle's Nest" now operates as the Suffolk County Vanderbilt Museum.
We learned from the mistakes we'd make with the prototype version of the spear, so we double-checked all our measurements before we cut the pieces for the body and ribs of spear 2.0. By definition, experimental archaeology is not about getting something perfectly right the first time around. Mistakes happen! We prefer to think of these as learning opportunities, however. As we continued forging spear 2.0, we encountered plenty of learning opportunities.
For example, during our forge day last weekend, we simply could not get the forge welds to work properly! As a reminder, forge welding is essentially gluing pieces of metal together; some sort of silica-based element, such as Borax, is needed to act as a bonding agent. Puzzled by our misbehaving wrought iron, the expert blacksmiths decided to do a "spark test" of each piece. Spark testing means carefully pressing metal pieces against a running wire wheel to see if there are differences in the "explosion patterns" of sparks; one can then infer if metal pieces contain differing elemental compositions, such as higher concentrations of carbon. As it turns out, our spark test revealed that the wrought iron piece for the ribs had a higher carbon content than the bar for the base!
The ancient Celts did not have access to electric wire wheels that spin at several thousand RPM (rotations per minute), though they knew how to drill holes in various materials, as evidenced by a number of perforated pendants and ornaments found in Iron Age graves. Additionally, while the ancient Celts did not have the in-depth knowledge about the physical properties of iron and carbon molecules as we do today, they certainly would have known that iron ore from certain sites behaved in certain ways. Unfortunately, because of the literal sparks flying and social-distancing rules, we did not capture any photos of the spark test.
How did we circumvent our forge-welding issues? Essentially, we had to bring both wrought iron bars up to a near melting point. By doing so, we can trick the molecules of various elements, such as carbon, contained within the metal into thinking that they are from the same piece and should stick together. Of course, to bring a charcoal forge up to roughly 2300 degrees F requires large amounts of two components: fuel and air. Jokingly, we jotted down in our forging notebooks "this requires a butt-load of heat and charcoal." While sounding like a jest or slang, "butt-load" or "butt-tun" is an actual unit of measurement. "Butt" was a medieval term describing a large, wooden barrel for holding liquids (equivalent to roughly 130-150 US gallons) or a wooden cart for carrying said barrels.
We cannot know for certain if the ancient Celts encountered similar issues when forge welding. However, we hypothesized that if they had, this may be one more reason for why trees carried multiple important or even sacred connotations in the Iron Age....fuel. Charred wood, or charcoal, is a critical main requirement for pyrotechnic crafts, including blacksmithing. In other blog posts, we've noted that wood and trees were considered likely special or even sacred materials as evidenced by their restricted use. To quote from our "Smiths of the Iron Age" post, "For example, archaeologists encounter the "old wood problem" in excavating and analyzing Iron Age burial mounds. The "old wood problem" refers to how the wood found in some Celtic tumuli (burial mounds) was reused from earlier structures and thus skews the dating of the burial. In other words, the wood used in the burial mound is often older than the construction of the burial itself. It is thought that in Celtic society trees and nature had significance, possibly even religious/spiritual connotations. Various trees were seen to have different meanings, many of which have been lost to time. The oak was often seen as a prominent symbol and a highly sought-after hardwood. Like modern blacksmiths, ancient smiths would have preferred hardwood as the charcoal for their forges because of its low smoke rate and high concentration of heat. Smiths are able to control fire and harness its transformative qualities to change unassuming lumps of metal ore into fantastic objects - this process may have been viewed as magical and thus the smith as a kind of sorcerer."
Stay tuned for further updates, as we hope to get back to the forge next month. Be safe and keep learning!
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