Darrell Markewitz is a professional blacksmith who specializes in the Viking Age. He designed the living History program for L'Anse aux Meadows NHSC (Parks Canada) and worked on a number of major international exhibits. A recent passion is experimental iron smelting.
'Hammered Out Bits' focuses primarily on IRON and the VIKING AGE
... in early preparation for the October 13th bloomery iron smelt at Wareham
The standard furnace build here by DARC uses a mix of rough thirds of powdered clay (EPK), course sand, and dried, hand shredded, horse manure (last year's droppings). This last adds short pieces of softened grass that act to bind and leave spaces for steam to escape to limit cracking.
When done, the exterior is wound with rope to help prevent external sagging (seen at the bottom of the image. The furnace body was 20 cm tall at that point.
The interior is filled with a dry mix of half sand, half wood ash (from the wood stove). This acts to both stabilize the structure, but also pull moisture from the wet clay. This image taken roughly 20 hours after the lower portion had been finished. The darker ring in the packing next to the walls shows absorbed moisture.
In high 20's C clear Ontario weather, the soft clay had already dried to 'leather hard, when work resumed the next day'. Because I had some concern about the relative moisture between this layer and the next one to be added, I had incorporated a 'Beardsley Break'. A depression is made on the top edge with your thumb, creating a U shaped channel. In this way if the expected crack develops between the two additions of clay, the channel will both lock the new upper section in place, but also serve to limit / prevent any working gas seepage at that band.
Finished clay build. Furnace is actually straight!
The bulge at about 40 cm is because the section of previous furnace had thicker walls than the fresh clay build below. The internal diameters match. This is the first time I have attempted to directly re-use a section of an earlier fired furnace.
Total shaft height at 62 - 65 cm.
I am expecting some cracking problems with the mating of fresh (shrinking) and old (stable) clay sections. Once the furnace has air dried and then gently heated, it will be bound with fencing wire to brace any cracks Iike the loop seen on the re-used section. (The rope is removed when leather hard)
I intend to mount four pieces of angle iron into the inner corners of the block plinth to ensure stability. All in aid of being able to re-use this furnace several times, hopefully.
All day : Early start (8 AM), expect delayed extraction (early evening)
This smelt will be a continuation of the recent evaluation of a mechanical system that mimics a Norse type twin bellows. This continues trials undertaken at Smelts 94 and 95
- Past experience with lower air volumes suggests this will be a longer and slower burn.
- This will be a roughly 20 - 22 kg ore smelt, with the expectation of a smaller (3 kg?) bloom.
- This is a fixed experiment (not teaching), but those visiting can expect the usual 'Darrell rambles on'.
- There will be limited opportunities for direct participation.
This is an 'Open Invitational' event. Contact Darrell via e-mail if you wish to attend.
Furnace base, metal form in place for first clay additions
I have positioned the furnace to the SW corner of the smelting area, back towards the low retaining wall. This will place the tuyere to the right hand side (the side seen here), with extraction towards the open side (left in image). The standard concrete half blocks used as a base plinth, packed with charcoal. I have framed up the extraction arch side (bottom made with two clay bricks) and created a pocket based with charcoal fines for the purpose of collecting tap slag.
First course of clay build, after form removed.
I have been taking advantage of the atypical hot and clear weather for mid September to prepare the materials and doing the build much earlier than has been done in the past. Starting Friday past, I have made up a batch of analog, which is drying nicely in the hot sun. Two afternoons were taken to generally prepare the working area and hand shred enough dried horse manure to make up the needed two batches of the standard clay / sand / manure mixture that has become the standard here. Yesterday the first batch was made up and applied, building the bottom part of the furnace to about 20 cm tall. This mix was a bit on the soft side, so the spiral rope binding was placed a bit closer spaced than normal. This course may be left an additional day to ensure it is stable enough to support the next course addition. There is part of the wall cylinder remaining from the last smelt (94, as seen in this image). I hope to save some work and materials by trimming the edges square and placing this ring as the top section of the new build.
The intent is to retain this furnace body against future smelts. The reason for placing the furnace to one side of the area is to leave room to also construct another stone block furnace, like the one used for Smelts 82 - 84, 86, 87 (only with a bit more care to even construction). This with an eye to a potential special event marking Smelt 100 / 70th in November 2025.
As part of my recent attempt to (somewhat?) re-integrate into the Ontario (Eldormere) branch of the Society for Creative Anachronism (1) I will be mounting a bloomery iron smelt, assisted by other members of the Dark Ages Re-Creation Company.
This will take place over Friday through Sunday, June 21 - 23, at the 'Baron's Brouhaha' camping event, near Tiverton (Grey County) : https://ealdormere.ca/canton-of-northgeatham/barons-brouhaha/With the full iron smelt happening all day Saturday June 22
The Build - Will be similar to the the standard 'short shaft' used for Smelt 85 :
• clay build, mix of EPK dry clay with pulverized furnace wall material (from Smelt 94)
• set on shallow plinth of stone blocks
• base of charcoal fines, about 10 cm
• 25 cm ID / 60 - 65 cm total shaft height
• tuyere of ceramic tube, 2 cm ID
• set to 15 - 20 cm above fines, at 22 degrees down angle, 5 cm beyond interior wall
• estimated working stack height at 45 cm
• extraction arch at roughly 20 w x 10 h cm
• tapping arch at roughly 10 w x 5 h cm
The furnace will be constructed from late morning to mid day Friday. Gentle drying fire into that evening.
Test One : The use of pulverized wall material from a previously fired furnace mixed (roughly) 50/50 with fresh clay. Normally fresh material has been used for new builds, the standard mix being thirds by volume of powdered clay, course sand, and shredded horse manure. A mix using old furnace walls is the normal method used by Lee Sauder, who has excellent results, but this is the first time for our team. The expectation is some additional care needed during the initial drying stage.
Air set up - Smelt 90 'Wind & Weather' - October 2021
Air Supply - Will be similar to the arrangement used for Smelt 90, which will pair both a theoretical Norse twin bellows (enlarged for smelting) with an electric blower. This will allow alternately allowing individuals to use the bellows equipment, enabling comparison with mechanically delivered air. The bellows used had been created for the 'Vinland' series of experiments, at to date has provided air for 6 previous smelts. (2)
Sliding Air Gate, closed position
The air delivered from the electric compression blower will be modified by two gates. The first will be used to set the total volume of air delivered, which has been at least roughly calibrated for 100's of litres per minute. The second gate is a sliding one, designed (??) to mimic the kind of changing 'pulse' air delivery provided by the twin bellows seen above. On a repeat cycle of roughly once per second (rate is adjustable), the gate shifts from fully open to allowing only a smaller amount of air. The main distortion is that this mechanical system does not allow for any changes in delivered pressure, which is the case for the bellows method.
Experiment Two : The sliding gate / pulse air delivery had been previously tested in Smelt 94. The intent this time is to be able to directly compare and measure the delivery from both the mechanical system and the twin bellows within the same smelting process. Past problems with instruments has meant that attempts to generate absolute numbers have been inconsistent. This test should at least be able to provide relative measurements between the two air methods, so allow for correct adjustments of the mechanical systems to the human operated bellows.
Richard Schweitzer operating the bellows - Smelt 44 'Vinland 5' at L'Anse aux Meadows HSC
There will be some opportunity for observers to directly participate :
• A limited number of people can be directly involved as the working team. This can include both maintaining charcoal and ore ore additions to the furnace (two jobs).
• Throughout the smelt, large quantities of charcoal need to be broken and graded to size. Although certainly a messy task, this is something well suited to younger helpers.
• Individuals can take a turn operating the bellows. This normally undertaken on a five minute rotation.
• At the final extraction, a small group of dedicated hammer workers are required. Preference will be to those who have some related (blacksmithing) experience with sledge hammers.
First compaction of a bloom, well after dark - Smelt 87 '65 for 65', October 2020
It is expected that the use of the kind of air volumes indicated by the bellows will greatly increase the time per individual charcoal charge burning time, so extend the time required for the smelting process. (Smelt 94 required a total of 14 hours from initial pre-heat to final extraction)
This will be only the third time a full iron smelt has been undertaken at an SCA event in Eldormere. The working team from DARC to date has undertaken a total of 37 past smelts, the majority successfully resulting in iron blooms. For team leader Darrell Markewitz (aka Sylard of Eagleshaven) this will be his 95th.
Importantly, this is also a chance to see the process of experimental archaeology at work.
Notes :
1) My journey into Living History, so by extension, my independent creation of the Wareham Forge, and eventually research into bloomery iron smelting, all started with an accidental discovery of the very first SCA event in Ontario while an art student in 1976. By 2000 I had shifted my activities to the more specifically focused DARC.
Those who have been following my work for some time are aware that I have both submitted and been selected to contribute pieces for several small town 'sculpture walk' collections over the last decade.
This year I was extremely pleased to be one of two pieces selected for the Paisley Street Sculpture Project. This is a new presentation only in it's third year. A collaborative effort with Kelly Probyn-Smith of Elfworks Studios entitled 'Wave Action' had been chosen for the inaugural presentation.
'History in the Wind' was originally designed for a public artwork competition at Elora in 2017, intended to mark the 150'th anniversary of Canadian Confederation. The concept was to represent the contributions of major groups in the history of our country, portrayed as a series of weather vanes mounted to a central shaft. There is an earlier description of the design and the meaning of the individual elements :
The original 2017 design
The submission for Paisley was similar, but in the creation some modifications were made, and detailed here with images of the completed work.
'History in the Wind' as installed'
Beneath it all - the Land : The original layout suggested the use of larger granite stone for the lowest element. On more rational consideration, the simple logistics of moving such a huge stone was simply beyond my abilities. This coupled with the difficulties of boring a hole through such a large and hard material. As I did have a big pile of thinner limestone slabs (gathered off locally off the Niagara Escarpment), I decided to use one of these pieces instead. This was set on to the top of the steel plate base mount. The base was then hidden by a number of pieces of differently coloured granite stones and one of quartz, all found as glaciated field stones, intended to represent the Canadian Shield.
Turtle Island : The original layout had the figure of a turtle to represent the First Nations. On a bit more research, I could not find any reference to those Peoples using directional weather vanes. ('You want to know the weather? Just look up...') I was also having some trouble thinking how to build an elegant and functional element out of the intended wood. Thinking deeper into the concept of 'Turtle Island' I decided to take that more literally, and make a very large flat depiction of a turtle as the base element for the whole sculpture, at 36 x 30 inches. The outline carving of the shell plates are those from the common painted turtle, painted black and outlined in red. The paints used are red and black ocher, mixed with linseed oil. The turtle has head, tail, and feet made of hammered copper, the metal employed before the intervention of Europeans. The body is positioned so it faces north.
The Norse : Although a very brief episode in terms of the overall human occupation of this land, my own long association with Vinland lead me to include this element. There are a number of depictions of D shaped 'weather boards' mounted fixed to ship's masts, as well as surviving artifacts that had been retrofitted as weather vanes and put up on Christian churches. This element is made of brass sheet, with a surface punched depiction of the World Serpent from Norse mythology. The lower text is first in runes and Old Norse 'Kettil made me' (the character name I use in Viking Age living history demonstrations). The second text us in rune like modern English, 'Wareham Forge 2024 (the date in Roman numerals). In place of what would have been weighted ribbons are bronze wires ending in large hand made glass beads.
Europeans : I had originally chosen to use 1605, Champlain's founding of Port Royal in Nova Scotia, to mark the beginning of the European settlement in Canada, (not withstanding seasonal settlements like in Red Bay Labrador, some 75 years earlier). I considered actually forging this element out of antique wrought iron, but in the end used modern mild steel bars. The numbers are highlighted with a copper coloured paint. Although a modern type, the feather of the arrow is made of cut and slightly twisted galvanized sheet steel. This is the physically heaviest of the elements, and in proportion has the least amount of fin surface.
Lower Canada / Quebec : Rooster shaped weather cocks where a common shape seen in Catholic Quebec, a reference to the 'before the cock crows' reference in the New Testament. This one is made out of sheet copper, the body as two clam shell pieces. Again detailing is rendered by punch work.
Upper Canada / Ontario : In more secular times, roughly a century later, for Ontario the most common figure found on weathervanes was the running horse. This specific outline is based on an object in the collection of the Royal Ontario Museum. As the artifact, this is made of tin plate, the material chosen already slightly weathered.
Into the Modern Age : The top element is a rotor like variation on an anemometer. This made of stainless steel sheet. Individual arms have central rotating disks to create a further impression of wind driven motion. Additionally the disks are covered with holograph film, with the hope this will catch the sun and increase the visual component.
The finished sculpture is large, including the 4 x 4 foot stone base, standing a closer to ten feet tall. The individual elements vary in size, but all fit into the four foot diameter of the base.
Ken Cormack beside the completed sculpture
'History in the Wind' is located in downtown Paisley, on central Queen Street North, along the west wall of the Paisley Arena. It will remain in place until mid - later October.
Both the entire sculpture as seen, or any of the individual elements, are also available for purchase, after the public presentation of the work. Overall price has not been calculated yet. Cost of individual elements will vary, and a separate mount will need to be created for any of these purchased individually. (Contact Darrell at the Wareham Forge
I would especially like to thank Ken Cormack of the Paisley Street Sculpture project for his patient assistance in installing the sculpture. Individual positioning nuts had to be tediously hand threaded down the length of the main supporting spar from the top. (Some of those down as much as 7 1/2 feet of threaded rod!)
Organized by Lloyd Johnston, at Upper Canada Village, Morrisburg, over April 26-28.
I have to admit here that I signed up largely to support this ongoing series of experienced blacksmith demonstration events that have been orchestrated by Lloyd, who I have known since my earliest days at the forge (the late 1970's). The featured artisan blacksmiths have been drawn from a wide regional circle, individuals that Lloyd knows and felt would have something to offer. Fellow participants come from not only Ontario, but due to the location at the far east, also from Quebec and into New York.
Matt Jenkins is generally known from his '366 Hooks', a project he undertook which was then formalized into a traveling exhibit by his business partner (and wife) Karen Rudolph. He had traveled from his own Cloverdale Forge located 'north of Winnipeg', Manitoba, part of a larger round of demonstrations through into the western USA then back home again from what he mentioned.
Matt proved to be both a good technical demonstrator, but also an engaging one. His past as an artisan interpreter at the Fort Gary historic site certainly shows in his delivery method. Places where some would have gaps (heating a bar for example) were easily filled with stories, both entertaining and insightful. Matt also has the skill of being able to talk while he works, providing additional description to the processes. He has a very 'folksy' manner, which covers over a keen mind, his background training (in engineering) and considerable working experience.
Overall I was pleasantly surprised.
Given how long I have been at the forge myself, I was more expecting perhaps a different approach to things I already knew. One clear difference worth watching (for me) is that Matt works consistently with mass (where I tend to favor line). My friend David Robertson says that if he gets one new insight or working method in a demonstration, he feels it worth the time spent. The observations from the engineering side often provided just that. Matt certainly gave me a few new things to take home and consider adding to my own work.
Some of the decorative elements Matt demonstrated that caught my eye:
'Basket Weave' element, square punches linked with butcher tool lines.
'Leaf' element, using 'Deer Hoof' punch.
Unnamed element ('Thumbprint'??), using a dished end punch.
Have you wondered exactly how to get started as a hobby blacksmith? This
book offers valuable advice on how to get started the RIGHT way, and
may both keep you working safely - and save you money on those first
tool purchases!
Topics include : • Getting the right HAMMER • Firing the FORGE • Picking an ANVIL • Working SAFE • Tools and workshop • Motion Dynamics • Picking a Course
This
book is based on over 45 years personal experience working at the
forge, since 1992 as a professional artisan blacksmith at the Wareham
Forge in Ontario, Canada. Darrell Markewitz has guided hundreds of first time blacksmiths through an ‘Introduction to Blacksmithing’.
A physical
demonstration of many crafts activities requires the use of high
temperatures as a transformational method. Those involved with living
history presentations have a secondary problem, as modern generated
heat sources (torches) or containments (metal ‘fire bowls’) are
obviously not historic methods.
Land owners may have established a ‘no ground fires’ rule. There
are several underlaying (logical?) reasons :
- Not wanting surface lawns to be damaged.
- Not wanting to have pits dug into the ground
- Concern about transportation of fire wood, or gleaning activities
- Concern about potential dangerous spread of a poorly managed fire
- Concern about the liability aspects of burn injuries
Generally these
concerns are expressed by three commonly stated rules :
- Only fires on
raised metal fire bowls
- Only fires in specific pre-determined and equipped locations.
- No open fires of any kind
Event organizers
need to be fully informed of the technical requirements related to
individual craft methods. The physical size or working dynamic of a
specific activity may itself impose limitations on how to properly
and safely layout a fire based heat source. This is especially the
case for historic demonstrations which will require the use of wood
or charcoal fuel. A good example would be glass bead making, where
modern practice is to use bottled gas torches the historic method is
using a small enclosed clay furnace, charcoal fueled.
Often the response
when contacting event Organizers, who may be constrained by simple
rules dictated by land owners, is something like ‘You can work at
the edge of the single shared camp fire.’ This is not a workable
solution, as craft working requires considerable control of fire
sources, if not specialized builds entirely. The desire for a
companionable ‘fire circle’, or need for group cooking are just
not compatible for the technical requirements for metals casting as one
clear example.
There are a number
of possible solutions that can be utilized by conscientious and
experienced crafts workers that should fulfill at least the
requirement for general safety and prevention of ground surface
damage. Artisans need to explain these solutions in clear detail,
Organizers need to understand physical requirements.
Contained Fires
Many historical
craft techniques utilize fires inside specifically fire proof
containers. Examples would be small glass bead making and metal casting
furnaces. Larger and longer duration fires for ore smelting, pottery firing,
even bake ovens, again all require durable containments. In all cases
the purpose of these builds is specifically to hold the fire inside,
concentrate and control these fires for correct function over time.
Because of this technical requirement for fine control of heat,
constant management of a very specific sized fire is necessary. In
all these cases, the fires are normally contained inside clay or
brick walled structures, and can not be in any way considered ‘open’.
Even the most
extreme of all the potential fire based historic methods, bloomery
iron smelting, requires a structure intentionally designed to
withstand internal temperatures in excess of 1350 °C, over a day
long operation.
Experiment /
Demonstration of ‘Celtic’ bronze casting by Rey Cogswell during
their Master’s studies at University College Dublin in 2018. Clay
walled melting furnace to rear, stone walled crucible warming fire in
front, both mounted above ground surface.
It is understood
here that without general permission to use ground fires, any
structures using pit or banked construction can not be used. Given
the large disruption to ground surface that is required for larger
dug in kilns or furnaces, Artisans should always ensure specific
permission before undertaking these builds.
Surface
Protection
For Organizers,
recognizing the added value provided by fire based demonstrations,
the simplest solution is to position those activities on ground which
can not be damaged. An area already of plain dirt or gravel, like the
edge of a parking surface. This also prevents any possible accidental
spread of fire effects beyond the working area.
Often land owner
rules will state ‘raised fire, just because this is the easiest description. It is
expected that Organizers will be logical when considering the
following long proven options for safety and limiting surface damage. The question needs to be considered :
‘How high does ‘raised’ actually mean?’
The easiest way for
Artisans to avoid any potential damage to surfaces is to first lay
some type of completely fire proof covering down and build the
furnace or fire on top of this. The cheapest, fastest and most
protective method is to lay down a group of standard concrete paving
slabs. These slabs are typically 45 mm thick. Using four pieces at 60
x 60 cm yields a completely fire proof barrier big enough for the
largest furnaces. Although a bit bulky to transport, these slabs are
durable and available at any building supply, at a 2024 cost of
roughly $12 each.
Iron
Smelting Furnace built on concrete pavers preserving a
grass lawn. At Western Michigan University, International Congress in
Medieval Studies, 2013.
Smaller furnaces
can be built on special purpose refractory plates, such as pottery
kiln shelves, or even on slabs of thin stone.
Demonstration
of the high temperature Aristotle iron re-melting
furnace. This furnace is about 20 cm at the base, and safely sits on
a refractory plate. At a Society for Creative Anachronism event.
If absolutely
conserving lawn grass is a consideration, lay down a standard wooden
shipping pallet, then place the same concrete slabs on top. This
method was first devised in 2005, when a full iron smelting
demonstration was mounted on archaeologically sensitive ground
(Canadian National Blacksmith’s Conference at Annapolis Royal NS).
It has been used repeatedly to also conserve concrete flooring and
decorative lawns, and proven to have virtually no impact after being
removed. Positioning several lengths of 4 x 4 lumber will also leave a protective air space below the concrete plates.
For smaller
furnaces, the same effect can be achieved by laying down a couple of
cut to fit pieces of standard 2 x 4 lumber. In either case, and
potential heat transmitted downwards through the fire proof plate is
vented by the air space created underneath
Faced with the
problem of not damaging archaeological ground in Britain, but still
wanting to create a historic looking solution, the long standing
living history group Regia Angolorum (back about 1990?)
developed a protective design suggested by a panel from the Bayeux
Tapestry.
In it’s simplest
form this is a set of clay bricks, placed loosely on the ground,
contained in a wooden framed box. These can be covered with a thin
layer of sand, which both hides the more modern bricks and also will
fill any gaps between bricks. The basic design can be improved by
laying a piece of light sheet metal down first. More elaborate
equipment is also constructed along the same principle, with use of
short legs to lift the entire surface clear of the ground. This form
is more commonly seen in European re-enacting, where the problem of not
marring archaeologically significant ground is always present.
No
details of who / where. The fire surface appears to be a 10 cm deep bed of sand seen to the left end. – uncredited internet source
These fire boxes,
on the ground or raised, were introduced as a response to a specific
problem inside a specific region, they are also being applied for
cooking purposes only. A slightly smaller version may be suitable for
supporting smaller furnaces (metal / glass bead work). These
activities require quite specific heights for safe and efficient
working. Again, physical transport needs to be considered, with
table frames, crates of bricks and pails of sand.
It is worth
remembering that the most common solution suggested, a completely
modern stamped steel dish, is not suitable physically for containing
a craft working furnace or kiln. What is required for any of this
equipment is a flat supporting surface, not a depressed bowl.
Value of
Experience
Organizers need
remain aware of the value of the accumulated experience of individual
Artisans. This may be considerable, and certainly any long working
artisan will be fully aware of the operating dynamics of their heat
sources and safety measures involved. Rather than applying a simple
blanket rule, individual cases need full consideration. Organizers
should never forget the considerable effort undertaken by Artisans, and
the overall value any physical demonstration brings to their event.
G
M
T
Y
Text-to-speech function is limited to 200 characters
August 29 - October 10, 2016 : 'Turf to Tools Two' Project Grant
Canada Council
August 2014 : 'Turf to Tools' Travel Grant
Ontario Arts Council
February - May 2012 : 'Bloom to Bar' Project Grant
February 15 - May 15, 2012 : Supported by a Crafts Projects - Creation and Development Grant
COPYRIGHT NOTICE -
All posted text and images @ Darrell Markewitz. No duplication, in whole
or in part, is permitted without the author's expressed written permission.
For a detailed copyright statement : go HERE
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