Monday, March 31, 2008

SMELTFEST 08 - Experiment Notes

The rough layout used for the three main smelts I was involved in at SMELTFEST 08 is seen below:

There was some variation on the placement of the bellows plate and the set up of the tuyere on each of the three smelts.

The experimental data for each of the three smelts has been formatted up and posted to the Wareham Forge iron smelting series:

I will be writing up a description of each of these smelts, with some images attached over the next week or so.

(sorry about the use of remote links - but Blogger just does not publish tables correctly)

Wednesday, March 26, 2008

Air Volumes - Smeltfest 08

For the three smelts undertaken over March 15 / 16 / 17, the furnaces were set up to use the 'bellows plate' system which Skip Williams and Jake Keen had first worked with at the Eindhoven event last spring.

The system uses a thin ceramic plate that covers the part of the furnace around the tuyere that is subjected to the highest temperatures. The thin plate is intended to radiate off heat and thus resist melting. There is no actual tuyere, instead the air is applied through a tube that sits some distance away from, yet aimed at, the blow hole in the plate. In effect the rapidly moving air blast creates a venturi effect which draws in considerably more air than is provided via the air pump itself.
This effect was quite noticeable. It should be considered when looking at the raw numbers below, as these are a measure of the air inside the tube itself. There would have been considerably more air available on the inside of the furnace.

(I have removed the table I posted up here previously - as I realized this morning I had made a major error on how I interpreted the data, and thus crunched the numbers. Expect a corrected version with comments the first week in April.)

Tuesday, March 25, 2008

what the forecast says:

Tonight..Snow at times heavy ending early this evening then cloudy
with 60 percent chance of flurries. Clearing overnight. Amount 2 cm.
Wind southwest 50 km/h gusting to 70 diminishing to 30 this evening.
Low minus 5.

what is REALLY happening...

This is the view out the tarp cover from the workshop entrance at about 4:30 PM. Visibility is ranging from about 300 metres - down to white out conditions. The snow started about 11 this morning, about 5 cm down here so far...

Overview - SMELTFEST 08

...a fast overview of the 10 days:

THREE smelts undertaken, using the 'blast plate' method.

ONE test of the DARC Dirt 1 bog ore analog (in one of the furnaces above)

THREE additional smelts observed. These were the 'monster bloom' sequence by Sauder and McCarthy - resulting in a 175 pound bloom mass.

ONE smelt observed using all Colonial Era methods, at Colonial Williamsburg by Browder and Mankowski.

a DOZEN uses of the 'Aristotle Furnace' developed by Williams.

DAY TRIP to the Jamestown Archaeological site to view artifacts related to the first American iron smelting.

DAY TRIP to gather several hundred pounds of the Jamestown/Williamsburg iron ore.

A special participant in SMELTFEST 08 was Jake Keen from England. This years session was especially packed with smelting, and everyone felt they had not only a wonderful time, but learned and achieved a great deal. Thanks again to Elizabeth and Lee Sauder for hosting the workshop.

I have roughly 300 images, plus the detailed smelt data and various related field notes to organize. Exp

Thursday, March 13, 2008


For the next 10 days I will be off to visit and smelt iron with Lee Sauder and Skip Williams in Lexington Virginia.
Lee and Skip are largely responsible for the current interest in experimental iron smelting in North America. Regular readers will have seen their names used often in earlier postings here.

Lee's workshop, the Rockbridge Bloomery, can be said to be the birthplace (maybe 'spawning ground') of this activity. Fellow activist Mike McCarthy will be in attendance, working with Lee on a large, multi bloom sculptural project. Rounding out the core team is Dick Dawson of the Peter's Valley Craft School (site of the 2006 Early Iron Symposium). A special guest this year is Jake Keen, a widely traveled and experienced smelt master who is flying in from England for the workshop session.
Adding to the general mayhem are Steve Mankowski and Sheldon Browder and their group from Colonial Williamsburg. Plans are to spend a couple of days on their home turf, looking for local bog iron ore and helping (?) them out on an early American period smelt.
Skip is building a ceramic plate style smelter like the ones he saw and worked with last year at the big European Iron Symposium in Eindhoven, Holland.
I am interested in running this type as well, so using the 200 kg of charcoal I'm bringing down from Bruce Cowan's Black Diamond operation, we hope to undertake two, perhaps three smelts. One major experiment for me will be a full scale test of the DARC Dirt 1 bog ore analog. I have prepared about 50 kg of this material with expectations of producing a mid sized bloom in the Eindhoven furnace.

So - I will be out of touch until some time after March 24 / 25. Expect some field reports on SMELTFEST later that week.

Iron Smelt Movie Test

I was preparing some clips as part of a proposal to demonstrate at Quad State Roundup in September. One thing I generated is a small sized movie (at 1.9 MB) that could be used on the Wareham Forge / Iron Smelting web site.

The test clip was processed into a Quick Time file (.mov) via iMovie on a Mac. It would be interesting to see if various of my readers here can actually view the movie file on their machines.

The clip is part of the record made during the 'Icelandic ONE' smelt undertaken here at Wareham in early October (Thanksgiving weekend) in 2007,

to view the clip - use the link

for more background on that specific smelt, go to

Monday, March 10, 2008

DARC DIRT ONE - draft notes

Bog Iron Ore Analog:

A post this morning on Early Iron has lead me to jump the gun a wee bit, as I am working up a full report on this work for later in the month.

The team here (mainly Gus Gissing) have been working towards creating a 'bog iron ore analog'. One continual problem we have endured is wide variation in ore sources and qualities. Nature of the ore in turn effects the fine details of smelter design, and determines the characteristics of the blooms produced. With continual changes in ore type, it has been quite difficult to establish a predictable production from individual smelts.
Based on Gus's earlier work on 'Mars soil analogs', we took a look at what iron oxides were commercially available. Pottery supply companies sell a number of iron oxides as red pigments for glazes. Under the name 'Spanish Red' the material is is listed at 96.5 % Fe2O3 and 2 % silica. (I'm trying to trace down what the balance is). It is also available in a finer version through places that mix paints or sell base colours for printers inks, but is considerably more expensive in that form. It is also used to colour concrete, but I have not been able to track down some place that sells it in the kind of sizes we require. I expect the concrete pigments might be even cheaper.

The 'Spanish Red' is the cheapest of the straight Fe2O3 powders. It comes in 25 kg (50 lb) bags for about $50 CDN. The stuff we can get here in Ontario comes in a grit that is a bit finer than flour. As other iron experimenters have found, straight from the bag it is just too fine to work inside the kind of air blast our various smelter designs are producing. To get around that problem we are creating an artificial 'bog iron ore analog' (christened DARC DIRT ONE ).

The starting point is 80% by weight of the Fe2O3. We also were concerned that straight out of the bag it might prove too 'dry', so to get some extra slag production we are adding 10 % by weight of fine white silica sand. This is sold around here at Home Depot as 'decorator sand'. I suspect a plain beach sand would work fine too. The last component is 10% of plain white flour. This is basically inert, and serves as a binder. The powders are mixed by shaking in a large container with a (tight!) lid, then enough water is added to make a paste. The paste is then spread out to dry, our suggestion is in a layer about 1 /4 inch / 5 mm thick. The dry paste is then broken up with your hands to pieces roughly 'pea to peanut'. For the small batch tests I just spread the paste on a cookie sheet and set it under the wood stove for a couple of days.
From the looks of our test batches (one lb / 500 gm scale) I think you will want to run the broken material over a fine screen, say a window bug screen on a frame. Any of the dust can just be added into the next batch. The larger pieces are ready for your smelt.

This mix compares chemically and mechanically pretty closely to the samples of natural bog ore I dug in northern Newfoundland. (I say this knowing quite well that 'bog ore' can look a lot different from region to region!) At this point that assessment is based on the mark one eye ball, we have not done any detailed testing of the material we have come up with yet. One potentially huge advantage to the use of dry oxide powders exists for those involved in detailed archaeological reconstructions. Other small amounts of oxide powders (many also available at pottery supply) can be made to the base mix to simulate the specific ore contents from a given geographical location.

Gus (through his business Harder Gissing Machining) has donated enough of the oxide for two production batches. I picked up the the materials over the weekend. Todays work is to mix up a full production batch of DARC Dirt 1 in preparation for a full smelting test. As we are completely buried here under snow, with temperatures below freezing, I will not be able to just spread the past on a plastic sheet and let it air dry as I would hope to. I bought a bunch of thin aluminum foil 'oven liner' pans and will spread the paste on those and stack them in the kitchen oven to dry. Figure (hope!) a couple of hours at 200 F will do the trick. My aim is to prepare 25 kg (50 lbs) of the analog to use in a smelt next week with Skip wen I am down at Smeltfest at Lee's place in Virgina.

So expect a full smelt report on the use of the analog later in the month.

The post on Early Iron had mentioned using ground magnetite. This is sold at the pottery supply as 'black iron oxide'. The chemical form of this is Fe3O4. It is also a very fine power, and is actually half the cost of the red oxide. We intend to also make a full scale test of this source material, using a similar mix to paste, dry and crush. The chemistry of the black oxide is a bit different, which may or may not influence a smelt.

Using the Spanish Red, the cost per smelt (a bit over 25 kg / 50 lb 'ore') will work out to about $55 CDN - roughly $1 per pound. The huge advantage is that this material is easily available and will be standard smelt to smelt.

Saturday, March 08, 2008

Bead Bellows Reconstruction

This is part of the 'I'll Huff and I'll Puff' project.

This new bellows is being built for Neil Peterson, primarily for use in his experimental series related to Norse glass bead making.

The frame and layout is the same as that was used for the reconstruction of the Viking Age blacksmith's bellows. For details on the logic of the reconstruction, I refer you to earlier posts on that topic.

This bellows was constructed using only two of the lens shaped leathers. This gives a maximum possible loft of about 38 CM - which in practical use actually works out to the 36 cm total on the illustration. Any wider than that and you are stretching against the leather. Remember that our working numbers were something around 30 cm.

This image shows the internal contruction. I put a thin sheet of metal as a half circle on the inner side of each of the parts of the inlet valves. Note that there is a rim of leather left loose beyond the metal - this overlaps the size of the hole and remains flexible to make a better seal. The metal is roughly the same size as the hole in the plank.
You also see the inner support to the leathers. This is a piece of 1/2 x 1/8 flat which is bent to the same shape as the outline of the plates. This limits how much the bag can expand or collapse in under the pressures of filling or expelling. (Note that my set does not have this stiffener - instead it is double seamed with a piece of heavy wire inserted.

The second image shows the difference between totally collapsed and totally open.
First you see that totally collapsed, the effect is that the top plate sits parallel to the bottom one, at the same level as the top of the head block. This marks the 'dead air' at the maximum limit of an exhaust stroke. In actual practice, you might not actually stop as low as this.
So for calculations, only the upper triangle shape (illustration below) is available for air delivery.
One other thing to note is the way the sides of the leather bow in, even with the stiffener, at maximum fill height. This effect is actually more pronounced if the plate is not raised to maximum.
There is a slight opposite effect as the plate is lowered. You do notice that with the plate at the bottom of the stroke, the bag has collapsed in again. So I think the flexing of the leather bag is more significant in terms of limiting INTAKE, than in reducing output.

What is most sigificant to our calculatons is an effect we have not considered, which is 'valve lag'. This system requires some (significant) time for the valves to fully close at the start of an exhaust stroke. The valves are forced closed through two effects, a kind of inertia lag, plus the force of air outwards as the chamber is compressed. I think the wrist snap that Mark taught us works by mainly increasing the action of the inertia effect. In any case, there remains a significant difference between the top of the inlet stroke and the actual sealing of the valve (and thus the air available as exhaust volume). Its pretty darn hard to measure this working along (or maybe at all without much more sophisticated instruments). I estimated the difference was about 5 - 6 cm. I also suspect that this would be a relatively 'fixed' mechanical effect. At our standard 30 cm loft, the working seal would still be achieved at a drop of 5 - 6 cm. This means something about a 15% loss right off the top.

Jens Jørgen (at the Heltborg Museum in Denmark) is using a bellows with the valves located on the bottom plate. With that system, gravity is the first effect on closing the valves rather than inertia. I suspect this greatly reduces this potential loss - and would explain why he gets such good air volumes from his equipment.

I do think this reconstuction is more efficent than my set of the same size. The smaller bag (less folding) and stiffener both make for a larger fill volume. Tests will tell. I still don't think these are close to the required volumes for an iron smelt in practice however.

Friday, March 07, 2008

Caught between a Grant and a Hard Place

For those who have been following my Life, the Universe and Everything, you likely have twigged into the fact that I have wangled my way into an invitation to an upcoming iron smelting symposium in Denmark. I suspect what my have happened is when my friend and occasional partner in smelting crimes Skip Williams was not able to attend, I managed to talk my way into that open slot.
The symposium itself is free, plus they are housing and feeding us. Very cool. However GETTING there is problem. I had some money stashed away against the soon to be required replacement of my truck. This time I decided to seize the day. (The days are starting to get shorter, and 'saving for a rainy day' gets stupid when your whole life is in the drizzle anyway.)

I had occasion two weeks ago to stop by and visit the new workshop of Sandra Dunn & Steve White (TwoSmiths in Kitchener). Sandra has done a bit of smithing related research travel. She told me to apply for a Grant. Now, I had looked into both Ontario Crafts Council,the Canadian Council for the Arts and the Heritage and Culture Ministry back in 2005 for the presentation at CANIRON 4. No joy.
So this time I was not expecting much. But as my long time friend Brenda Roy says : 'You don't apply, you can't get anything'. (She also has received support on occasion.)

The piece below is a good chunk of the letter I composed to request consideration for even making an application. I did contact a number of organizations to see what the response might be. The letter outlines the problem....


I have just (Feb 18) been invited to attend an international symposium in Denmark:
"Iron Smelting Seminar in Thy"
Thisted Museum / Heltborg Museum
April 29 - May 4

My involvement with historic iron smelting is an extension of my work for Parks Canada, I designed and produced the 'Norse Encampment' living history program for L'Anse aux Meadows NHSC. ( I have been involved in work related to public presentation of this aspect of Canadian history since 1993, including work on a number of the major traveling exhibits across Canada and the USA to mark the millennium of Leif Ericson. On iron smelting itself, I have been working since 2001, with academic papers, workshops and public presentations in both Canada and the USA. (
I have been a professional artisan blacksmith since the mid 1980's, with a considerable body of work (

The opportunity to travel to this international symposium on historic iron smelting represents a significant event. I am the only Canadian who has been invited (and also the only North American who will be attending). The event itself bears no cost, but I remain responsible for travel to and from Denmark, plus within the country itself.

The smelting of bog ore to metallic iron was carried out by the Norse at Vinland (L'Anse aux Meadows) circa 1000 AD marks the first processing by Europeans in North America. The exact methods used represent a totally lost craft tradition, techniques abandoned before the first written descriptions, which also left minimal artifacts to archaeology. My challenge has to be to attempt to re-create the tools and processes that may have been used.

I have been working with forged metals since I was a student at OCA in the late 1970's. I established the Wareham Forge in 1992, which balances between museum related work, teaching, and original art metalworks. I also have curated a number of gallery exhibits of contemporary artists (the current project, 'Grave Goods', is in the jury process right now)

To date I have personally undertaken about 30 experimental iron smelts, and helped out with at least a dozen more. This is technically one of the single most difficult metalworking processes, and one for which there are no written descriptions, hardly any physical evidence, and certainly no living craft tradition to draw on. Serious attempts to re-create these ancient methods did not start until the late 1990's. With my start in 2001, I'm really part of the cutting edge of a new field of work entirely. Obviously you need to know how to make the metal itself before any attempt can be made to utilize it for objects!

I constantly run into this same problem: Art or Culture? My approach to this work is from the aspect of museum studies, I am attempting to re-create a process from Northern Europe during the Dark Ages (focus on 600 - 1000 AD). To date I have physically created about a half dozen metallic blooms, and have only worked two of these down to bars. From bar this metal could be then taken and used for raw material for objects, but that part really is identical to the other work I undertake as an artisan blacksmith. Certainly I do have a body of work taking modern metals and using them as the raw materials for objects with historic themes.

By the way the two aspects are sliced - ARTS wants to look at the object created only, but at least considers the artisan. This specific extensive body of work with iron smelting is about process, not product. (It has been suggested I try to spin the smelting process as 'performance art'.) CULTURE is channeled through the Institution only, and since I am an independent artisan, I do not qualify for consideration.

It turns out I am not really eligible for any of the EDUCATION related grants - as I am not enrolled as a student. I have been undertaking independent studies in this area for decades, and have amassed a considerable body of data and experience. Although I have published 4 academic papers, I hold no degrees. I have been a guest lecturer at universities ans have created and taught a college level program on the Viking Age, but again as an independent I do not have a sponsoring institution.
My hope is to find some financial support against the approximately $2000 this specific symposium and related museum research in Denmark will cost.

Grave Goods - First Artist Selection

The first meeting of the jury for Grave Goods was on Wednesday March 5.

In so much as almost all the people who had work viewed had been hand
picked and invited, the work was uniformly of a high standard. There
were a few submissions from the various open calls, and not surprisingly,
that work as well was of excellent quality. Those artist who gave some
outlines on the types of objects they wanted to contribute showed a wide
range of ideas and approaches to the theme. The scale of the objects
suggested is also very wide. Urns were a popular choice of course, but
there are also a number of large sculptural pieces (a couple just at the
limit of what can be moved up to the second floor hall).

Taken altogether the range of the submissions and the abilities of the
contributing artists is going to make for an interesting show!

For the first jury round, we limited ourselves to artists who had
physically sent in some kind of application on paper. In some cases this
included images (mostly as digital on disk), but at least a 'letter of
intent' was required. (This because I have verbal commitments from a
number of folks as well, but with my limited brain power those are
harder to keep track of.)

The current listing of contributing artists juried for inclusion to
Grave Goods :

Caz Bently - wood block prints
Janis Book - forged metals
Pat Burns-Wendland - hand spun weaving
Larry Cluchey - wood turning
Sandra Dunn & Steve White - metalsmithing
Dianne Edwards - marquetry
Kelly Green - wood carving
Lydia Ilarion - fine metalwork
David Ivens - metalwork
Lloyd Johnson - forged metals
Darrell Markewitz - forged metals
Rosemary Molesworth - ceramics
John Newman - forged metals
Kelly Probyn-Smith - metalwork
Mark Puigmarti - forged metals
David Robertson - forged metals
Brenda Roy - fine metalwork
Rob Schweitzer - tablet weaving
Graeme Sheffield - forged metals
A.G. Smith - illustration
Steve Strang - painting & drawing
Ruth Swanson - ceramics
Laura Travis - stone carving
Cathering Vanvakas Lay - blown glass
Sara Washbush - metalwork
Brigitte Wolf - stained glass

At this point those 25 artists are on board for the exhibit. This
compares to the total number involved for either of the earlier two
presentations, Reflections and Furnace. So we have an exhibit! I have had verbal replies for at least another 10 or so artists. I will
be poking them over the next couple of months to get a formal
application to the jury.

You will notice on the list of media that there is a dominance of
'heavy' crafts. If YOU are an Ontario artist who might
be interested, especially those involved in graphics or textiles, or know of someone who might be, go to the Grave Goods website for general information.

The details on submisison requirements are available on the web at:

of course feel free to contact me if you have any questions:

Tuesday, March 04, 2008

ONGOING - notes on what is happening

I see that I have been late in applying any new materials here for the last couple of weeks. Truth is that things have been extremely packed - many of the individual projects will be of interest to the regular readers here:

'Iron Smelting in Thy'
I have been nailing lodging and working out the details of my trip to Denmark for this symposium. I will try to report on things that may prove valuable:
- How to find a reasonable price room in Denmark.
- Applying for a Canada Council grant.
- Overview of planned Museum visits.
- Details on the symposium contents.

'Bog Ore Analog'
A project that Gus Gissing is doing the underlaying research on to create a kind of synthetic bog ore for our iron smelts. I will be undertaking a full scale test latter in the month with Skip Williams in Virgina.

'Smeltfest 2008'
The annual intensive smelt research week with Lee Sauder and Skip Williams at Lexington Virgina. This year will include a smelt at Colonial Williamsburg with the gang there, with gathering their local bog ore. Expect a field report on the activities in late March.

'I'll HUFF and I'll PUFF'
Experiments with early period bellows. Right now a number of test prototypes are being built to evaluate various bellows designs. Neil Peterson is working up theoretical models based on the measurements. A session at Forward into the Past (Kitchener-Waterloo, April 5) will provide raw numbers on produced volumes. All data for a paper under consideration.

there is a pile of other stuff going on too - but may or may not yield any reports to publish here


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

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