Wednesday, June 27, 2012

Working in 1812

More or less...


This was my set up as a Coppersmith at the 'Wharf at York' event over last weekend.
As it turned out, the majority of my time was spent running kids through a simple *tin plate* project - making a punchwork bracelet.

Although the days were long and weather hot, the event itself was exceptional. The blending of staged scenes by the actors and the living history interpreters proved both highly interactive and informative. All involved are keen to repeat and expand the presentation for next year.

Monday, June 18, 2012

Don't try to Talk the Talk

 - If you can NOT Walk the Walk

Sometimes I just can't stand it!
The piece before is copied directly from a post I wrote this morning for the Norsefolk discussion group. I suppose it comes off a bit high handed. 
 
Several loud voices had been droning on about Viking Age armour types. Which morphed into grand statements about VA blacksmithing skills. And then the comparisons between Japanese (late Medieval and later) sword making techniques...

I can see by a shift to a textile related subject that many are fatigued by the recent thread on metals, armour, weapons and blacksmithing methods. I also have kept out of this, until I just could not stand it anymore.
I have seen an awful lot of theory (read WAG) and little based on *applicable* direct knowledge / experience.

Techniques based on 20th century (post 1855 Bessemer steels and propane gas forges)

experience is of limited value to clear understanding.
Working a VA 'sand table' forge

Modern metals just do not behave like historic ones. Antique wrought iron is a distinctively different material than ancient bloomery iron. Propane heat has its own characteristics, as does rock coal, as does the only fuel utilized in the VA, which is charcoal. The equipment set up of the forges for each is completely different. The welding processes used at the forge retain the same base mechanism, but the actual processes used in detail are different with different iron metals and also with different fuel/forge set ups.
Popular culture ideas of how forge welding *actually* works are simply quite wrong.

Both wrought iron and bloomery iron have a distinctive chemistry and a distinctive physical structure. You make some shapes using quite different methods than when working with modern materials. Core to this difference is the existence of microscopic layers of glassy slag within the body of the metal. Any given piece of material will vary not only between pieces, but even as different spots within the same block.
This is also completely the case with the amount of carbon present within an individual iron bloom, which most definitely are not uniform in alloy content (as our modern metals are).

This difference in structure due to slag content is critical to any possible understanding of the relatively difficulty of creating shapes using VA type iron metals.

VA iron plate cook pot
It is in fact the single most important factor on which to base any further discussion. Skill of the smith is variable, but does not change the fact that it is the material itself that is what is dictating the possibilities.
Simply put, the slag inclusions will cause the metal body to crack and shear, especially when subjected to strain, especially as the piece of metal gets thinner. These are almost always *diagonal* lines - virtually impossible to forge weld tight again when creating thin pieces.
That is why 'currency bars' from the VA most commonly have one end flattened out to a paddle shape. This was a clear indication of the relative quality of an individual bar. Metal with larger amounts of slag still remaining would shear as it was flattened.
*This* is why large thin plates are not seen in Viking Age artifacts. Almost without exception, iron plates are never any wider that 20 cm. Those plates that do exist are quite thick, with thickness in the range of 4 - 6 mm (that's 1/8 to plus 1/4 inch for the Americans). Even the thinnest is two to four times as thick (and heavy) as modern steel sheet used for almost all contemporary armour making. (Check the actual thickness of the metal in an artifact cooking pot.)

People hold up Japanese forge working (especially bladesmithing) techniques without understanding exactly what the purpose of those elaborate folding and welding techniques *is*. The core purpose of the Japanese method is to produce a highly refined block of metal, eliminating as much of the slag content as possible. A secondary purpose is to control the carbon content of the iron alloy, more importantly to 'average' out the available carbon within the block. The theoretical existence of many thin layers is totally incorrect. (Due to carbon migration at welding temperatures, much over '1000 layers' those individual layers totally blend to a consistent mass and effectively disappear.)

Those who talk about the difficulty of welding twisted cores for VA pattern welded blades either have never actually undertaken this process themselves, or more likely are referring to early *failed* attempts to duplicate this process. These experiments in the 1960's have been widely duplicated in popular illustrations. (The most obvious culprit is the 'wrinkly people book' - The Vikings, published in the early 1970's)

My own 'Sword of Heroes' - 2 cores, each 9 layers
You simply *do not* take a bundle of round rods, braid them by twisting, then attempt to weld the bundle. Although it is remotely possible to achieve a weld in this way (with great skill), the odds are extremely high that the resulting block will be full of voids.
No, gentle readers, the *correct* way to forge weld up a pattern welded blade is to start with a set of flat plates (typically 3 - 4 cm wide, 3 - 4 cm tall and 10 - 15 cm long) and forge weld that flat stack into a block. Then the block is drawn out to a long octagon. Then that is what is twisted. It is then (typically) hammered back into a square cross section. Only then are the individual core rods welded back into a long rectangular shape to create the starting material for the eventual blade. (And yes, this is exactly how *I* do this.)

The exceptional sword found at Sutton Hoo is consisted of a total of eight central core rods, each rod forged from a welded block made up of 7 to 9 layers (x-rays not entirely clear), with an edge layers applied in addition. The total number of welds required far exceeds those needed to create a Japanese technique blade. 

Difficulty is based on the number of welds required - not simple layer counts (which is a *geometric* progression after all.)

Saturday, June 16, 2012

Wharf at York / 1812 - Toronto

I will be participating as one of the artisans demonstrating at the 'Wharf at York' which itself is part of the larger 'Redpath Waterfront Festival' running from June 21 - 25.
 The event is happening down at the Ferry Docks, in a small park just to the west there. My booth station is set to the west end of the presentation space, close to the water.

Wareham Forge sales booth, 'Festival of Nations' event, Chatham - roughly 1990.
 This is not exactly what you will see (!) I am re-building my ancient wood frame booth with the tarp cover into a small workshop, with several heavy benches to mount various tools, plus some shelves to hold some set dressing objects.

Louisburg, Cape Bretton - 1999
 And this is not quite what you will see me doing.
Curiously, for this event I will be demonstrating coppersmithing and tinsmithing.

This is a free event!
Thursday : 10:30 to 8
Friday : 10:30 to 8
Saturday : 11:30 to 8
Sunday : 11:30 to 6

Come out and visit!
My demonstration will include limited hands on activities for people to participate in.

Thursday, June 14, 2012

'Ore to Axe' - Video Trailer

See an earlier post here for purchase details...

Wednesday, June 13, 2012

Air inside a Smelting Furnace

(This altered from a posting to Don Fogg's Bladesmith Forum)
View PostHannes N., on 12 June 2012 - 10:49 AM, said:
We where mostly successful... some experimental runs with ores of low quality or with an effort to evaluate the influence of one or the other paramenter on the process failed.
Gallery

Here in Ontario, my team (DARC) has been working backwards towards Viking Age styled air delivery systems. As well as using vacuum cleaner blowers (at least three different ones) we have used replicas of the side by side VA blacksmith's bellows, plus two different oversized versions built just for smelting. A couple of times we have attempted using rotary blacksmith's blowers (usually as an emergency when electric blowers failed). A couple of years back I invested in one of the same high volume industrial blowers that is Lee & Skip's standard. I did build a monsterous prototype mechanical box bellows at one point. (For the English here, I've even got a 'Bouncy Castle' blower, but frankly have never used that one!) The only system I have not worked with directly has been the classic 'Great Bellows' style. I have worked around the team from Colonial Williamsburg (Shelton & Steve) when they have been using one of those to good result.

Because my group here is interested in Viking Age iron smelting, possible air systems based on that historic period are of great interest. We have worked a couple of smelts using the 'bellows plate and blow hole' system that Michael Nissen of Ribe introduced me to. Our normal is an insert tuyere. On that we have used ceramic, steel pipe, and most recently the forged copper type that Lee introduced.

We have kept spotty records through all this of air delivery volumes and pressures. I rigged up an in line fitting that goes between the air control gate and the tuyere. This is not the most accurate, but at least in comparison gives us some numbers to work with. The volume is measured via a simple aneonometer (normally used by wind surfers and the like) and an older pressure gauge. Lee had shown me using that kind of wind speed measure (which he had used for his earlier experiments). All our values are being calculated / translated back into standard values (Litre per Minute & mm of mercury)



One of the things I personally have found a bit frustrating in reading reports by other experimenters is that people often do not give any kind of estimates (or even descriptions) of the air systems they use. As you are experiencing, not only how you set up the tuyere, but exactly what size and kind of blower / bellows system you use can make a huge difference in the actual results in a smelt. We all dwell on the variations on ore, but it is safe to say that *air* is perhaps more critical. (Even with a good ore, the wrong air set up or volume / pressure can drastically effect your results!)

Neil Peterson and I have been collecting data, and hope to pull enough together for a formal paper.(Theoretically for the ICMS at Kalamazoo next Spring ???)

Mike McCarthy had postulated (way back at Early Iron 2 or one of the first Smeltfests) that the air into the furnace makes a torus shape. The lobe at the top bigger than the one at the bottom due to heat effects. With a tuyere set horizontal, this hot air washes back onto the upper wall especially to errode it. Tipping the tuyere angles the torus so it sweeps out over more of the interior of the furnace volume. The size of this torus is determined by the volume of air. The penetration of the torus into the interior of the furnace is determined by the pressure.

You can see how this is effecting smelts with low volume and pressure. The air more or less 'bounces off' the charcoal contained in the bottom of the smelter. This limits the size of the 'hot spot' inside the furnace to just against the front wall. Much of the ore falling down the inside ends up at the rear wall, too cold to really add mass to your developing bloom. The effective slag bowl is smaller, and again mainly laying against the front side of the furnace. The developing bloom is itself smaller, and with less reduced and sinter temperature ore available, tends to be lacy in structure.

With lower air you would be consuming less charcoal. Your overall yields of ore into bloom are much lower. Anything you gain in terms of saving charcoal is easily lost from both lower yields - but more importantly from how much more work is needed to effectively compact that lacy bloom into a working bar.

Don't mis-understand. I'm not saying you can not get iron produced with a lower volume smelt. So many people (primarily in Europe) have proven that over and over. The few surviving artifact blooms however look much more like the dense 'puck' blooms that are the result of our high volume air smelts. Something is going on there!

We think there are some big potential cultural implications around the whole question of effective air systems for Viking Age smelting. With so little (or vague) archaeological evidence, this might be more an interesting speculation than anything else.

Friday, June 08, 2012

ANCIENT IRON at Goderich Celtic Festival

http://www.celticfestival.ca/fr_home.cfm


This year marks the 20th anniversary of the Celtic Festival. (August 10 - 12, 2012)
At this point I am the only artisan to have attended every single year since the start. Over the years I have also been a feature demonstrator, illustrating some aspect of historic metalworking methods Saturday and Sunday afternoons.  I have also taught at the associated Celtic College every year it has been in operation. (August 6 - 9)


Those in regular attendance at the Festival have seen how I have slowly incorporated elements of history and experimental archaeology into my presentations. I feel it is necessary to understand the real past of Celtic culture, if we are to fully appreciate its modern expressions. The 'Celtic Roots' of the current visual arts are based on ancient objects. Knowing these forms, and understanding the physical techniques that created them, is fundamental to a true understanding of the Celtic World.
'St Padric's Bell Shrine'

Those who know me well also realize that I am the 'Norseman in the woodpile'. My initial interest in ancient artifacts and design was actually focused on Celtic Iron Age and the later 'Book of Kells' material cultures. But I got swept up in the Viking Age, and have concentrated my studies and work there. Perhaps not so curiously, my favourites among ancient objects come from the period circa 800 - 1000 from Ireland. At that time and place there was a collision  between Norse and Celtic, pagan and Christian, and the artistic styles reflect this blending. Both Celtic and Norse cultures were well known for the brilliance of their metalworking skills, and this also shows in these objects.


So this year I wanted to do something quite different.


Ancient Iron : Smelter to Forge in the Celtic Iron Age

Celtic College Course Proposal / Description
The Celts were one of the first primary 'Iron Age' cultures, with iron the materials for tools, weapons and decorative objects. How was iron actually made? Then having an iron bar, how did they work it?

Norse Sand Table Forge
This is an intensive program, limited to four students. A historic style charcoal ground pit forge will be built, using hand bellows for air, and small artifact type block anvils. Students will directly experience the challenges this equipment presents by making a number of simple objects. Work will include making a cloak broach and simple knife blade, working with actual antique wrought iron.

On the last day of the program, students will build an actual iron smelting furnace. They will also assist in preparing materials for a full demonstration smelt to take place Saturday at the Festival. This is a day long special event to mark the 20th anniversary, which interested students will be able to directly take part in.

Requirements: Students must wear long pants and closed shoes to class, other safety equipment will be provided.
Previous experience blacksmithing helpful, but not required.

Materials fee: There is an additional course fee of $20 (per student) to cover charcoal and wrought iron materials.

This will be a half day session, Monday through Thursday (exact time periods to be determined)

Those students interested in pre-booking this course should contact me via e-mail.
Physical Demonstration for Festival

Bloomery Iron Smelt

As in past years, the featured demonstration will echo the courses offered at the Celtic College. A cornerstone for Festival goers, Darrell's ongoing demonstrations on Saturday and Sunday afternoon always educate and entertain.

Although best known from their cast bronze artifacts, the Celts were one of the first primary Iron Age cultures. It was iron, forged into tools and weapons, which allowed the Celts to have such a dramatic impact on all of Europe.
Extracting the Bloom
But just how did they make iron in the first place? I turns out that the exact processes used by the ancients are unknown, for our modern methods are vastly different. To mark the 20th Anniversary of the Earth, Air, Fire and Water Festival, a unique demonstration is planned. One which will employ these forces at their most elemental level.
Drawing on over a decade of experimental archaeology research, a team will build, prepare, then fire, an ancient styled bloomery iron furnace. This process will take some 8 hours, culminating in the extraction of 5 - 10 kg white hot bloom mass.
Supported by individuals from the Dark Ages Re-creation Company, Darrell is the single most experienced 'iron master' in Canada, and one of the very few working with these techniques in North America.

The Celtic College program outlined above is a ambitious one,  representing an absolutely unique learning opportunity. For the program to go ahead, a minimum of * four registered students * will be required.

The iron smelt at the Festival itself will be undertaken reguardless of this. To ate, this will be only the * fourth time in Canada * this type of demonstration has been mounted at a major public event.

Hope to see you there!

Wednesday, June 06, 2012

'Ore to Axe' - a review

Ore to Axe
This documentary film details the process of smelting iron ore into metal and forging it into an eighteenth century-style axe. Follow blacksmiths with over 100 years collective experience as they demonstrate every step in the centuries-old bloomery smelting process. By combining earth, air, and fire, they create that "tool of necessity" used for generations.
Blacksmiths Shelton Browder, Ken Koons, Steve Mankowski, and Lee Sauder take you on the journey of finding ore, making charcoal. building a furnace, smelting the ore to iron, converting the iron to steel, and finally forging the axe. If you have ever wondered how the tools so important to our ancestors were made, watch and see skills almost lost to history.

Title #336053
Format: DVD-R 
Disc Price:
$29.95
Available from
or by searching on Amazon.

Anyone who has been following the current 'Early Iron' movement in North America can not fail to recognize the name Lee Sauder. Lee, working with his smelting partner Skip Williams, has had the single greatest impact on the re-discovery of lost bloomery iron smelting techniques of any other individual. You will see him mentioned frequently in my own writings, most certainly his example, sharing and friendship have had an immense impact on my own life in the decade since I first met the pair.

Shelton Browder and Steve Mankowski are known in historic blacksmithing circles from their prominent roles at Colonial Williamsburg. Each in turn has served as principle blacksmith there (Steve currently, Shelton just retired). They were more recent additions to the yearly 'Smeltfest' research group that Lee hosts, but I had first met them back in 1991. Their understanding and skills in Colonial era techniques and technologies is second to none.

I wanted to state my close working relationship and friendship to the primary characters in 'Ore to Axe' right up front. It is hard to give a truly unbiased review of something when you know the participants (and instigators!) so well.

The key to assessing 'Ore to Axe' is in understanding what it *is* - and so, what it is *not*.

What this 52 minute long production *is* - an excellent visual documentary showing an entire working  cycle of smelting iron to producing a working tool from that iron.

What the DVD is *not* - intended to be a concise training course on the illustrated techniques.

Film maker Ken Koons (Split Log Productions) has used a simple and clean visual style to document a complete cycle.
Timber is felled and converted to charcoal. Ore is gathered, roasted and broken. Clay is prepared, a form is built, and the long process of building a furnace is shown. Using the furnace, an iron bloom is created. The bloom is cut and compacted into a working bar. Part of the metal is converted from iron into steel using a re-melting hearth. Then this iron and steel is used to replicate a specific historic pattern axe. The film ends where it has begun, the new axe being used to cut another tree for the next batch of charcoal.

Koons has chosen to let the images tell the story.
Narration (by Browder in his role as story teller) is more of an overview than a set of technical descriptions. The sound of all the activities is 'live', but there is minimal conversation from the participants, certainly *not* a running explination of 'I'm doing this - because'.
There are some absolutely great detailed sequences of things like slag tapping, bloom forging and axe making. All of the action depicted is real time working processes, nothing has been 'staged' artificially for the camera.

Much information is there for the viewing - providing you have the patience to *observe*. In this the film maker, and participants, have chosen to utilize a traditional form of communicating skills information. In fact an older format that suits the whole look and feel of the production. Those willing to watch the video many times are sure to pick up new small details on every viewing. This is the instructional method (watch, watch, repeat) that was the core of the older apprenticeship learning system.

There are a few times that specific sequences might have not worked quite well as intended. When the camera was placed on the end of a log being chopped, so the vibration of the strokes shakes the image, specifically comes to mind. These small flaws are more than compensated by clear close ups of the step by step details of the various metal working processes.

The whole production has a kind of 'Boys in the Hollers' feel to it that most everyone I have viewed the DVD with has found quite charming. This is enriched by a simple soundtrack of original music played by Koons and Sauder themselves. Browder's voice has just enough of a Virginia drawl to lend colour, but still remains crystal clear in understanding.

At this point, I have watched 'Ore to Axe' three times, with three entirely different groups of people.
The first time was its premier showing, at Smeltfest 12 in March, with all the principles involved seeing the final production for the first time. Needless to say, this could be considered an expert (and overly familiar) audience. There was a lot of 'why did you do this that way', 'hey, that really worked' and 'Steve, get your thumb off the hammer'.
The second time was back at Wareham, with the members of the DARC iron smelt team (none of which had actually ever met the characters, but only knew them from my tales). There was a lot of 'did you see that?' and 'oh, now I get it'.
The third time was with one of my blacksmith friends / students. Her observations afterwords pretty much matched my own. 'There is a lot of meat there, but you have to watch and pay attention'.


I would clearly suggest anyone interested in historical blacksmithing process purchase a copy of 'Ore to Axe'. It will certainly outline the processes of iron smelting for you to give you an understanding of just how the process works. The sequence of forging the historic axe will be extremely interesting (just on its own) and may suggest a tip or two.

I would absolutely recommend anyone interested in bloomery iron smelting purchase a copy of 'Ore to Axe'. Although not a detailed step by step set of instructions, that kind of cookbook information is available if you look for it. What this video will give you is a clear visual reference to not only a long proven working sequence at the hands of experienced practitioners. Seeing the tools employed, and just how they are actually used, is alone worth the price.

I think the best evaluation came from something Kelly Probyn-Smith had said :
"This is something just like I would expect to see on TVO." 
(Ontario's educational channel, our version of PBS.)

ORE TO AXE
Available from

Tuesday, June 05, 2012

Hals - from Iceland

A fast look at a smelt mounted (Saturday June 2) by Margrét Hrönn Hallmundsdóttir working as part of the Greenvilliage Grampus project (that's a Facebook link, sorry)

Margrét had been in conversation with Kevin Smith about his work excavating an 'industrial' level Viking Age iron smelting site at Hals in Iceland. The DARC team have also been working with Kevin towards a possible full reconstruction of the Hals / Icelandic working system.  Our 5th smelt in that series (interrupted for Vinland) was May 28. Over the last week a conversation in depth between the three of us has been going on.

Margrét should be extremely pleased with her team's results.
On their very first smelt, they got a roughly 3 kg bloom!

The images bellow have been scammed outright from her Facebook postings over the last week.
Consider the commentary a bit vague, as I am mainly pulling conclusions only from what I see in the images!

The base of the furnace under construction. Stone blocks defining a 'slag room', tap arch and grooved support for the tuyere. This marks one departure from Hals, where only small stones have been found, the construction is entirely turf slabs.

A close up of the tap arch and lintel stone. The rock is volcanic - Basalt with many small air voids.

Above the stone, grass covered turf (peat) is laid in flat slabs. A central cylindrical hole continues the line of the stone blocks. This hole is lined with about 3 cm of a mix of 1/3 hot spring clay, 1/3 sand, 1/3 shredded horse manure. At Hals the turf is laid to build a cone (so at 45 degrees).
An overview of the competed furnace, showing the air systems. The tuyere used was a length of standard Schedule 40 steel pipe. There is no specific evidence at Hals to suggest what kind of tuyere was used. Two air systems are in place. A medium volume, low pressure blacksmith's blower (circa 1880 +) and a small great bellows type (post about 1300)

Better view of the bellows. The small size suggests lower air volumes available. This type of bellows will allow a skilled operator to modify air pressure however (so blast penetration into the furnace interior).
Part way through the smelt (?) A nice looking slag tap. You can see that the initial block of turf that had sealed the tap arch has been removed, exposing the bottom of the slag bowl. Although its hard to tell from a photo, the thin tracery of cooling slag suggests a fluid 'happy slag' at this point.
At the top of the furnace, likely about the start of the burn down phase. The ore had looked to be fairly powdery, you can see the lightest fragments have been blown back out of the furnace mouth by the air blast. The original clay lining of the furnace has completely cracked away and fallen into the base. (Suggesting extra slag production). The central cylinder is still more or less in shape, and the wide turf slabs do appear to be containing the reaction gasses.

The extracted bloom under initial compaction. The darker material on the outside is slag, but the still bright core indicates the presence of iron!
The final bloom pieces? (No description with the image) Its hard to tell quality from an image. The shape and surface texture does suggest a lacy consistency, to be expected with the air systems used.

Just for comparison, remember the DARC team did not get any iron at all until our *sixth* smelt attempt.

Great work!!
 

February 15 - May 15, 2012 : Supported by a Crafts Projects - Creation and Development Grant

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