Monday, February 17, 2020

CAMELOT Medieval Conference : Call for Papers


Come to Camelot

The Conference on Archaeology, the Medieval and Experiential Learning of Tomorrow
Sunday, September 20, 2020
St Jerome’s University in the University of Waterloo

Call for Presentations, Papers, Workshops, Seminars, Events & Vendors!

This year, CAMELOT invites you to join us for a day devoted to the consideration of “Conflict and Cooperation, Space and Material Culture in the Middle Ages.”

The medieval world operated largely on the reciprocal relationship between conflict and cooperation, between individuals, groups and nations, all of which navigated an ever-changing landscape.  Military, social, environmental, political, and economic conflict were surprisingly often resolved through acts of cooperation.  Space, in architecture, urban planning, and agricultural, as well as imagined spaces (as in mythical places, literary settings and theological contexts), allowed individuals and groups to address these changes.  The result of conflicts often had immediate and important impacts on the material culture of the time.

We invite any interested parties to submit ideas for spoken presentations or demonstrations related to any aspect of medieval conflict, cooperation, space and / or material culture.  Topics for presentation may include, for example:

Ø  Military activities, conflict and cooperation
Ø  Environmental change and conflict
Ø  Political, social and economic issues
Ø  Vendor presentations on material culture including:
o   Blacksmithing
o   Ironwork
o   Heraldry
o   Food
o   Social Customs
o   Clothing
o   Games
o   Entertainment
o   Books and literature
o   Other
Ø  Architecture and building
Ø  Any medieval topic which excites and informs

We invite proposals from undergraduate and graduate students, members of the broader public, enthusiasts, re-enactors, artisans, craftspeople, experimental archaeologists and subject experts.  In short, everyone is welcome and encouraged to submit proposals. The aim of the conference is to educate, entertain and engage with a wide spectrum of interested presenters and topics.

To submit a proposal, please include the speaker’s or vendor’s name or names, title or topic, a brief 150 word abstract and full contact information (including mailing address, phone and email).

Email your proposals in DOC, RTF or PDF format to the conference organizer:

Jamie Zettle at Jamie.zettle@uwaterloo.ca

Deadline for submission:  August 30, 2020


My current plans are to attend the Woodford Furnace Festival (Ireland) and a return to the Scottish Sculpture Workshop for the completion of the Turf to Tools project. This will have me returning to Wareham likely September 18. 

Wednesday, February 12, 2020

Purchasing a Cook Pot


From a recent conversation to a potential customer :
On 2020-02-09 12:50 PM, D L wrote:
We are looking to acquire Viking cookware such as an Oseberg cauldron or say 7L or so.
from the original excavation report (cooking tools seen to right)
The Oseberg Burial cooking tools, with the pot set on the tripod
I think it goes without saying that because of the popularity of certain recent television programs, there has been a massive increase in items available that brand themselves as 'Viking'(1). Many (if not most) of which have only the vaguest reflection of actual Norse artifacts (not that I might have an opinion here!). For me, the mere use of 'Viking' as the descriptor in advertising (as opposed to either 'Viking Age', or more correctly 'Norse') from a supplier is a clear warning bell. There is also a considerable amount of lower quality gear being now produced in India - and as with all things, you get what you pay for.
I have seen a few options coming from the UK that vary greatly in price and often state that they are not food grade.
We definitely want to cook in them. What do you mean by « oatmeal sealed ». Is this a process that would effectively seam the seams to allow for cooking?
Ok - those pieces of information are important - and I am going to unpack the pieces:


On Viking Age Cookware: 
Interpretation based on Bengstarvet, Sweden, in mild steel.
There are two general materials used for cooking pot construction during the period : Wrought Iron / Copper Alloy

- Actual Wrought Iron is only available as an antique material in the modern world. I have only been able to secure the actual metal  in suitable sheet form * once * in my 40 years of making replicas and reproductions :
https://warehamforgeblog.blogspot.com/2010/07/iron-norse-cook-pot.html
- So what everyone is * really * using is modern mild steel sheet. Functionally, it really does not make that much difference on the cooking (or dying) side. Note however, that historic objects are made of far thicker metal than is seen in modern replicas. Thickness on VA pots is closer to 4 - 6 mm. Modern interpretations vary considerably, but most typically will be 1 mm (or less!)
- Many suppliers, however, are pushing * cast * iron objects, which were completely unknown in Europe until about 1600.
- A third related material would be stainless steel
(completely modern / post 1900), Our modern nickle alloy stainless steels which will never take the same colour as forged steel / iron.

'Copper Alloy' in Norse artifact terms is bronze, an alloy of primarily copper, with various other elements added in the mix. (It is this wide variation of elements and proportions that resulted in the shift of description in archaeology, starting in the 1980's) Actual bronze (high copper with tin) is difficult to acquire as sheet (in small quantities, here in Ontario at least). So a common substitute is brass (lower copper with zinc).
I have also made a number of pots (based on the artifact from Mastermyr) out of sheet copper.

Reproduction of the Mastermyr Pot - rendered in sheet copper.

Food Safe ?

So - again we go back to the materials, with implications from the construction methods.
Iron pots in the Viking Age are almost all made of many smaller segments, riveted together. There are two general patterns, either a cylinder with a slightly dished bottom, or a number of curved segments creating a sphere (think of orange segments). These seams are hammered close - but are not water tight.  The method of sealing the seams tight is to cook something especially thick and goopy (oatmeal a common choice)  and let this leak into and burn on to the seams. Then you never clean the outside of the pot.
Technically, this method would not be considered 'food safe' to modern health standards.

Exterior of a wrought iron reproduction pot, showing baked in oatmeal as sealant.
Note that using a forged steel (iron) pot has a tendency to darken the colour of food, this is only cosmetic, not a food safety problem.


It is possible to 'fake' the look of the correct construction by taking a commercial 'spun' pot or form, then hammering in lines (to suggest seams) and lines of tight rivets. This leaves you with an object that would look fine from say about 2 m distance. Also easy to perfectly scour clean the inside. Typically the spinning process requires quite thin metal however.
I have done this in past using stainless steel mixing bowls as the forms - it would represent a low cost alternative.

With copper alloys, both the cylinder and segmented construction have artifact samples. One other construction method is to 'finger overlap' seam edges (used in the Mastermyr sample seen above). Copper alloys can be soldered water tight.
- The potential problem with high copper alloys is that the green oxide formed (if allowed to sit for a long time without cleaning!) is poisonous. One possible solution to this is to 'tin' the interior surface. This method is seen in much later time periods, but little evidence is found on actual VA artifacts. Easy solution here is just to * clean your gear * after use!
- This all raises the most common problem with modern 'replicas', most especially those cheap end versions from the Middle East or India. Use of lead based solders, the lead being quite toxic! 

I would strongly recommend NOT cooking in any soldered seam pot that does not  specifically  list the use of modern 'lead free' (tin) solders.


I can report that DARC has used actual wrought iron and mild steel pots with oatmeal sealing, copper / brass pots with lead free solder joints - all for decades now in regular presentations. On a number of occasions for as long as two week periods. Never with a problem with food safety.

As to the thickness, I would have to default to your expertise.
Generally, modern industry is able to create much thinner sheets than available during the Viking Age. Although heavier sheet is available, it requires considerably more work effort to form (and big cost increases as raw materials - especially with high copper alloys).
The balance here is controlling cooking process over an open fire. Generally the thicker walls mean more even cooking. This is especially a problem with the thin stainless spun bowls I mention above. These work great for 'wet' cooking (like soups), but make it hard to control burning the bottom with thick stuff like stews.
I have a good supply of 1/8 thick mild steel (so 3 mm) sheet, if looking at one of the segmented iron types.
Note that copper is considerably more expensive as a raw material.
I currently have a full sheet of actual sheet bronze of suitable thickness (about 1.5 mm) on hand (chance find!)

As for an exact replicas, we are not an actual museum but we aspire to learn, to share and to be become as close to historical as we can given our means.
There are some general outlines on costing on the 'Norse Replicas' part of the Wareham Forge web site. Any specific object needs to be quoted individually.  As you can see there are a lot of variables depending on details.


Oh - one other thing. I've replicated the Oseberg Tripod a number of times - and much as I would like to sell anyone reading a reproduction :
This is an extremely problematic object - and most likely was NEVER an actual cooking tool.
The most accurate would be a simple wood pole tripod!  

Oseberg Tripod - My Interpretation
Tripods in the Viking Age - again

 
Norse cookware created for the feature film Outlander, in 2006. Also included a cauldron hanger and cauldron, and a 'slave chain'. The chain and the cauldron set are both clearly seen in the final film.

All the replicas seen here : by the Wareham Forge
 
 1) On a three minute search on the internet found a typical example : 'Viking Shield
- You will see on the 'about us' that there is absolutely no information what so ever about sources of the objects offered. 'In Business since 2000' does not inform you in any way what so ever about research, accuracy, materials, ...
(www.viking-shield.com/about-us/) 
Check the offerings listed as 'Feasting'. NOT ONE of those objects is based on ANY known Viking Age artifacts. Description of materials is in fact INCORRECT
(www.viking-shield.com/horns-feasting/feasting/) 
Fantasy designs, poor descriptions, lack of quality - and yes, cheap pricing = objects bulk purchased from India. 
Hot Links deliberately avoided. 

Monday, February 10, 2020

Experiencing the Viking Age!


 

Experiencing the Viking Age
August 1 and 2
( Saturday, overnight and Sunday)
Requires TWO confirmed bookings
 
be a viking


You have seen it on the television shows and movies - but what was it ACTUALLY like to live in the Viking Age?

This is an intensive two day and overnight immersion into the daily life during the Viking Age :
- a starting lecture segment on 'material culture' (objects and life)
- wear period clothes (provided)
- setting up your camp (replica tents and gear)
- preparing an evening meal ('cold food' as lunches - all provided)
- sleeping out in the tents (with suitable bedding)

Once camp is established, undertake a number of Norse handicrafts
- pewter casting in soapstone moulds
- glass bead making
Each resulting in objects you take home to keep!

Participation limited to FOUR individuals.
Children accompanied by parents welcome (8 years or older please)
Course fee of $450 (+HST) all materials.

For more details on this special program : Experience Viking Age

Monday, January 20, 2020

2020 Course Dates?

Tentative Schedule

Courses in Blacksmithing / History

at the Wareham Forge

http://www.warehamforge.ca/TRAINING/train.html
(note at this point the web site still shows ** 2019 ** dates)

Introduction / Basic Blacksmithing
April 17 - 19
July 18 - 19
Sept 18 - 20
Oct 16 - 18
Nov 14 & 15 (2 students only - propane)
http://www.warehamforge.ca/TRAINING/course.html

Build a Zombie Killer
May 23 & 24
http://www.warehamforge.ca/TRAINING/zombie/zombie.html

Introduction to Bladesmithing
July 4 & 5 (requires 'basic' level skill)
http://www.warehamforge.ca/TRAINING/bladecourse.html

Introduction to Bloomery Iron Smelting
Oct 10 & 11
(requires minimum 2 bookings)
http://www.warehamforge.ca/TRAINING/smeltcourse/index.html

Experiencing the Viking Age (new!)
August 1 & 2
(requires minimum 2 bookings)
description pending

- All programs limited to maximum FOUR students
- Course fees unchanged for 2020
- Deposit required to reserve a space

Generally courses are offered on the THIRD WEEKEND each month.
Private Session or Group Bookings possible for other dates - please ask.
Sorry, I do not offer any  3 or 6 hour 'experiences' - as in my (educated) opinion these are of little value.


a) Teens as students?

No students under 14 years of age accepted. Please read the policy :
http://www.warehamforge.ca/TRAINING/teens.html

b) Physical Requirements?

The Wareham Forge is not equipped or prepared to offer training to individuals with disabilities. Please read the policy :
http://www.warehamforge.ca/TRAINING/requirements.html

c) Location / Lodgings / Discounts / Group Bookings ???

Please read over the full descriptions provided before booking.
(details provided at the bottom of the Training page indicated)
Standard offering for a group booking is two days / four students = $1400 (+HST)
Available weekends are limited. You can also book on to any of the scheduled course weekends listed


hope to see you this year!

Saturday, January 18, 2020

Looking at 'Primitive Skills' - Iron Smelt

image copied from the Primitive Skills web site

I was directed to this set of videos by Jeff Evarts.
Jeff is a past student here (Bloomery Iron Smelting), and has an all round interest in ancient metalworking and related technologies. He posted the ‘Making Steel’ video to the ‘Iron Smelters of the World’ Facebook group, asking for opinions. (1)

Initially I watched the first video ’Steel from Ore’ (seen below), as available on YouTube.
The first time through I made about a page of notes.
The following day I dug deeper, hoping for some better information. This got me to the ‘Primitive Skills’ web site. This gave a second video, ‘Build Furnace’ (seen below) and a longer written description of the iron smelt process as a blog posting. Eventually I discovered a yet a third related video and description, of the piston bellows used.

Backing up step.

Just who is ‘Primitive Skills’?
http://primitiveskills.net/
" Primitive Skills; is the technique that “antediluvian” used to sustain life in the natural environment. These techniques are meant to provide the basic necessities for human life including food, water and shelter. "
quote from the Primitive Skills web site

Unfortunately, the combination of web site, blog postings and individual videos on the YouTube channel does not include any references to Who or Where.  (1)
Where : A few things can be deduced. It is clearly a tropical location. Bamboo is seen and used as a fundamental raw material. It appears the presenter is Indonesian / Philippinno? So a guess would be someplace over to SE Asia ??
Who : The presenter does not talk - at all. The blog is in English, but there are hints from the writing that this is not the primary language. (3)
This really appears to be a single person operation. The filming has the look of ’set up and walk into the frame, edit later’. (4) The demonstrator also certainly appears to be undertaking all the work involved himself, which is re-enforced by descriptions in the blog posting. This to me suggests an individual with a fairly good level of overall tool use skills. There are technical descriptions on the blog post detailing at least some understanding of the bloomery iron making process. So at the least some background research was undertaken.

One important limitation is that the sequences are ‘live - as it happens’. This means camera angles are sometimes not the best, or things just did not get filmed.
I consider it fundamentally important here to also consider the overall intent of the series. It is not necessarily to demonstrate the ‘absolute best’ methods. It is clear that the combined series is intended to record a progression of nothing to something - ‘Walk into the bush and make everything you might need’. (5)

A) ‘Build furnace to prepare for iron age’



I was not able to find a supporting blog post for this sequence - which might have provided some of the details only estimated here

Although I did watch this second, I think looking at it first will help with better understanding.

There is a very clear ‘chicken or egg’ thing going on. Initially the work is gathering bamboo, using a simple triangular bladed *iron* axe. Which comes first? So move past this, and figure this just as easily (with considerable more work!) could have been one of various stone tools, perhaps even copper or bronze. The series presenter does describe this whole series as ‘moving from the stone age to the iron age’.

The first third of the video puzzled me at first (the lack of commentary a problem). The demonstrator is shown cutting bamboo, preparing splints. At first, given the title, I though this was related to making an interior framing for the furnace build. In actual fact this was illustrating ‘making tools to gather materials’, in this case one of several baskets that get employed later. Not really important to the furnace build specifically.

The build is shown using locally gathered clay, then mixing and combining with some amount of grass, as long strands of flat blades. The exact proportions here can not be determined, but it appears that there is not much of this organic material in the mix. This suggests the grass (especially given its flat profile) will be acting only as a re-enforcing element. I have to mention that this looks like very nice clay, as he is able to use it straight out of the ground with only some extra water added. There is no indication that additional sand is added (to heat stabilize or increase temperature resistance).
Overall the clay mix appears fairly wet during the build process.

The first step in the build is placing a flat disk of clay (looks about 3 cm thick) down as a hard base. Honestly, I have no idea why this was done. Considerable experience has proven that the underlaying base ground has little effect on the operation of the furnace. If anything, placing a layer of clay under the furnace is likely to create more problems for later slag tapping or extraction of the final bloom.  The only thing I can think of here is that this may be some (poor) reflection of the build method seen in Japanese Tatara furnaces? (6)

At about 8:30, you can see the first course of wall constructed :
- The overall interior diameter of the furnace base (not given) appears to be about 20 cm.
- The walls are very thick, looking about 10 cm + thick at the base. 
As the build progresses, you can tell the clay mix has changed to a firmer consistency. About half way through building up, a gentle wood fire is started, eventually to grow to the entire volume filled with sticks. (Likely to firm up the lower clay sections before completing the build). There is then a sharp cut in the action, with next the furnace shown at its full completed height and form. This appears to be twice the base diameter, so another WAG + is to about 80 cm tall.

The tuyeres appear to be hand built. They also are a significantly different colour than the raw clay (even later when that is seen dried). This certainly suggests these have been pre-fired into ceramic. There is no indication about this given.

image is screen capture from 'Build Furnace'

Two clay tuyeres are seen :
- about 20 cm long
- interior diameter looks about 2 - 2.5 cm
- very thick walls, about 2 cm
You can see as the tuyere is added that it is placed very low, with little clearance above the hard floor.
At one point (9:10) there is a top down view, which shows the distance proud of the interior wall is about 1/3 the distance across the furnace, so roughly 6.5 cm proud.

image is screen capture from 'Build Furnace'

Of special note is a detail of the interior of the finished furnace, taken later in this sequence (at about 12:40).

image is screen capture from 'Build Furnace'

You can see the placement of the tuyere, the image shot through what would normally be the tap arch : 
- The angle of the tuyere is extremely flat, near as I can measure off the screen at less than 10 degrees.
- The height of the tuyere is at best equal to the it’s width. That would place the centre mark at best at about 6 - 7 cm above the hard base.


B) ‘Piston Bellows (Fuigo)’


There is another separate video sequence and blog post illustrating the construction of the double action piston bellows used.
http://primitiveskills.net/primitive-skills-piston-bellows-fuigo/

The whole bellows is made from a section of hollowed out log.
These are the measurements quoted on the blog section
Total Length = 100 cm
Total Exterior Diameter = 30 cm
Total Interior Diameter ≠ 20 cm
Working Depth (distance seen as stroke during operation) ≠ 40 cm

So a real WAG here on air produced is about 12.5 litres per stroke .
Stroke speed appears to be about 1 per second, so double WAG at 750 LpM (??)


C) ‘Making Steel From Iron Ore’



With the related blog posting
http://primitiveskills.net/primitive-skills-making-steel-from-iron-ore/

Again, the limited nature of details in the written commentary, especially coupled with the lack of narration in the video, limits clear understanding.

Initially, my eyebrows raised at ’Steel’.
Grumble, Grumble = Bloomery IRON is not Steel.
Reading the related blog posts however, did clearly illustrate that the individual behind Primitive Skills :
a) was not a primary English language speaker (3)
b) actually had some understanding of the chemistry and physical process involved

So - Notes on what is seen (rough film times) :

0:00 - 5:00 = Five minutes of gathering rocks.
This certainly appears to be a limonite Fe203 ore. The blog posting gives “iron composition at 53% to 56%” Which, if actual Fe content, is a pretty good ore.
My first question here is - ‘Why such such big pieces?’
The ore is obviously surface deposited, eroded out and misplaced from the bedrock underneath. Big pieces have not moved as far down hill from source. Are there not smaller pieces further downhill or along the stream bed seen at other points? Sure, you have less pieces to pick up - but there is sure to be a penalty in the ore preparation phase.
In the blog there is a description of only being able to haul 35 - 50 kg ore per ‘turn’, with ‘several times to bring it back’. This appears the only indication of how much ore was at least gathered.

5:00 - 7:00 = Two minutes of gathering logs, cutting lengths, splitting logs.
This really puzzled me. At first I though this was the start of charcoal making. So, ‘Why not use the branches you had obviously trimmed off?’. The real purpose here comes a bit later.

7:00 - 8:00 = Breaking big rocks into ‘half hand’ sized pieces.
There does not appear to be any sorting going on here. Obviously a lot of hard labour here (use of a rock anvil and hammer stone).

8:00 - 10:00 = Roasting ore.
So now you see what the segment of chopping and splitting wood was all about.
There is a nice sequence at about 9:20 where one of the roasted pieces is seen easily broken smaller - just by hand.
But honestly? THAT is why you roast a rock based ore in the first place! Roast, THEN break. Certainly smaller pieces are going to heat quicker to the critical temperature (convert to Fe3O4), but still…

10:00 - 10:45 = Breaking ore.
The majority of the effective work here is seen using a hardwood length as a mallet over a stone block. The particle size appears what I would consider standard for a limonite ore, being ‘rice to pea plus the dust’. If anything, the particles may be a bit on the small size. There does not seem to be much in terms of rock / silica impurities included.
There is a sequence showing the use of the water powered ‘hammer mill’ built in a different sequence. Again I can’t see really how effective this really was. The stroke rate is very slow, with a very reduced impact force. The wooden hammer mill does not appear to be having much effect on the rock pieces under it as shown.
In the blog he mentions it taking ‘a day and a night’ under the hammer mill to prepare all the ore. Honestly, in my own experience, he would have been much quicker just to have stayed with the hand mallet.

10:45 - 12:15 = Equipment and Materials
This sequence is a pan over the various materials, equipment and tools prepared and on hand for the smelt itself.
The clay tuyere is seen buried in a heavy ring of clay around the base of the furnace. This helps link the hollow bamboo pipe up to the piston bellows. The clay appears to add about an additional 10 - 15 cm thick band, about 10 cm tall, around the base.

10:45 + 11:45 = Ore quantity ??
I mention these quick shots, mainly because there is no actual data given on any of the quantities used in the smelt.
It would be an extremely rough guess (at best) to attempt to estimate how much ore was prepared, or if in fact this was all the ore actually used. This appears to be something about enough to fill  3/4 to 1 standard 20 litre plastic pail? My best guess is that this would run to about 40 - 45 kg of the ore (??)  (7)

11:45 12:00 = Charcoal
You see the prepared charcoal. The particle size here looks about the same as I would suggest, roughly ‘egg / golf ball’ to about ‘pea’.
There is mention in the blog that this charcoal was ’stored from the previous year’. Given the high moisture environment seen in much of the video footage overall, I would wonder just how much additional water that fuel had soaked up over all that time. (Use of fresh and bone dry charcoal has proved to make a difference in our own work here.)

12:15 - 12:40 = Plugging the ‘tap arch’
I have to admit, this really puzzled me.
The furnace was initially constructed with a tap arch, although this is not shown as part of the initial construction of the base area of the furnace. It may have been cut in after the walls had firmed up?
The size looks roughly 10 cm tall by at best about 15 cm wide. The arch sits above that heavy ring of additional clay. This places the bottom of this *possible* tap arch certainly higher in the furnace than the tuyere (likely about even with the tuyere OD top edge).
We see the arch being completely sealed with a very heavy addition of clay, packed and blended into the thick base walls.

12:45 - 14:00 = Filling and igniting the stack
You can see a long sequence of getting the interior filled and fully ignited. A few burning coals are added, topped with that appears the ‘standard measure’ of charcoal. Then the single (!) worker takes a turn at the bellows to get that fuel fully ignited, and the process repeated. Although again very hard to estimate, the amount of charcoal looks to be about half one of our standard buckets, maybe about 1 kg per addition (? again there is no description provided).
As the last fill to top is added, you can clearly see the large amount of very white ‘smoke’. This likely is as much steam as anything else (remember the comment about damp fuel). You can see the change at the top of the stack (smoke disappears), as the furnace becomes ready for the first ore charges.

14:00 - 14:40 : Charging Ore
Again, without numbers at best there are only WAG’s. It looks like about 500 gms  (?) or so of ore being added. The level at the top of the furnace is seen dropped perhaps 10 cm at most. This looks to be a pretty standard addition proportion.  You can also see the full ignition to a clear flame a the top of the furnace.
There is very clear reference made on the written description of the importance of smaller charges  of ore and charcoal, to evenly distribute ore though the working stack in the furnace.

14:40 - 15:30 = Main Sequence
Just a note on the edit. I thought the large set of short clips showing ‘more of the same’, especially the distance shots of bellows pumping, really helped to enforce the length of the smelting sequence itself. No specific note is made in the blog of how long the primary sequence to burning down took.
A reference is made to “After a hard working day…”

15:15 = Steam Venting?
Something I noticed here, which re-enforced an aspect I wondered about, and had been hinted at during the ‘block the tap arch’ sequence.
There was no mention of a drying fire (visual or in the blog). The furnace walls certainly appeared quite damp. At this point you see an image taken that clearly shows steam venting off the side walls of the furnace. With such thick walls, the danger of failure due to cracking never became a problem. But the amount of energy being robbed by driving off all the moisture in that very massive clay construction must have been considerable. Normally I would remain concerned that this would end up effecting possible internal temperatures, so the overall progress of the smelt.

15:50 = Tamping Down
The top surface of charcoal is seen being tapped down inside the furnace, which appears to have burned down to about half full.
This may be an attempt to tell just where the top of the slag mass is. The sound seems more like crushing charcoal to me, but in truth this is as much a ‘feel’ thing as a change in sound.

15:30 - 15:45 = Clearing Base
16:00 - 1630 =  Open Tap Arch
In the first sequence we see that the heavy ring of clay around the base has been broken free and removed. The exterior of the furnace is being carefully fractured in preparation for extraction (?)
In the second, the fill to the tap arch is broken out, exposing the slag mass within. There is no actual liquid slag tapped. This may be because of the thick wooden tool with only a squat point being used. This is seen not being effective in breaking through the solid bottom of the slag bowl.

Another significant problem is clear here. As a single person operation, including use of a manual bellows, the worker can either tend the furnace, or keep air flow and as a result operating temperatures maintained. Clearly, the whole furnace interior is starting to freeze up. (8)

16:30 - 17:00 = Extraction
The walls of the furnace are broken away, exposing the entire slag mass within
Near the end of this sequence, you can see how the slag has ran down to, and then fused completely, to that hard clay base built into the furnace.
Again, the complete absence of any liquid slag indicates the temperature in the entire mass has dropped below ‘about’ 1100 C (9)

17:00 - 17:35 = Freeing the ‘Bloom’
Clearly there is one solid block of slag, still with fragments of clay wall clinging to it. The brittle nature of the slag is clear by the way it shatters under the blows from the large wooden  (troll) hammer.
Eventually the much smaller mass of metal and clinging slag is broken out - only a small fraction of that large mass.

17:35 - 18:55 = ‘Compaction’ ?
(see the comment on video and visual temperature)
That there is an iron bloom created is not in doubt.
The material is entirely too cold at this point for any real effective compaction. The fact that the material collapses over the first strokes of the troll hammer is more an indication of how lacy and slag filled the results are. Dark slag is certainly seen breaking off, and remaining crusted on to the exterior.

18:55 - 1920 = Cold Hammering
An attempt is made to compress the surface further using a hand stone on a rock block. The metal is certainly far too cold at this point, both image and sound clearly show this.
I expect this was included primarily to complete the working process for the video.

The final sequence that shows the stone polishing of the bloom has clearly been added to ‘show there was bright metal’ - so an actual iron was created. The final close up images do show a considerable amount of visibly fluid slag still remaining.

image is screen capture from 'Build Furnace'

It is extremely difficult to estimate much about the results of this effort.
The mass appears to be about 15 x 20 x 10 cm, but it is extremely lacy and still includes a lot of slag.
My best estimate is, once that mass has been correctly re-heated and compressed down to a working bar, there will be significant loss. I would expect the end result will likely be about enough solid iron to make the triangular inset axe blade seen used in the first part of this series.

The main correction I would suggest is with the initial layout of the base and tuyere placement of the furnace.
- There is no need for that solid clay base. If anything this compounded slag control problems.
- The tuyere was set far too low in the furnace base. There simply was no room for slag to collect.
- The tuyere angle was far too shallow
- Taken together, this meant the slag bowl was not deep enough, not allowing the metallic iron to collect most effectively into a more solid bloom.
- With a working tap arch, (and depth to work) it might have been possible to tap off the obviously excess about of slag. This has been shown to help create a more solid bloom. (10)

Likely this also has proven that undertaking an iron smelt, especially if intending human powered air is most certainly not a one person activity! (11)

Taken altogether, the video certainly does illustrate the use of a primitive process to work through from raw ore to iron production. I certainly realize, as all viewers should, this was never intended to be a tutorial on ‘best method’.

Honestly, ‘Primitive Skills’ should be applauded for actually creating an iron bloom - working not only using such simple methods, but with what looks to be a first attempt, and most certainly by undertaking such massive effort working alone!


Notes:

(1) I have recently been criticized as being 'needlessly pedantic'.
If you are going to consider this report on my own observations, placed against experience, as stating the obvious and far too detailed : Please just turn to some other commentary.
It remains my experience, over a number of projects and decades of teaching and experimentation, that is is always better to state the obvious, than assume others know the details. Too many times I have seen problems caused by 'I thought you knew that', assumed in error.
I generally assume that most readers are not in fact familiar with the large number of earlier descriptive commentaries available both on this blog and over on the main web site documentation.

(2) I placed a comment on to the related blog posting, both making some technical observations and also suggesting that some description of the individual involved and the working location would really be helpful in assessing the information provided.

(3) I most certainly suggest anyone following the links (and I recommend reading the fuller blog description of the smelt attempt) be very considerate of the writing style. I see a few European usages (like ‘coal’ when ‘charcoal’ is meant).

(4) This itself not intended as a criticism. I use the same film technique myself - I suspect for pretty much the same reason. There is also every indication throughout that this is a totally one person production.

(5) This concept, of starting from bare hands and no tools, through gathering and processing natural raw materials through to production of all elements needed to create a finished object, now has the term ’Sole Authorship’ applied to it. I was first introduced to this as a recognized, systematic, process by Mike McCarthy (Mike was the instigator for the original ‘Gangue aux Fer’ and the first Early Iron Symposium.)

(6) In a Tatara, the initial clay construction at the base is fully intended to melt away during the smelting process. The rectangular shaped Tatara is also designed to make best use of fine ‘iron sand’ ores found in Japan. The final iron produced (called tamahagane) is log shaped, rather than the ‘half sphere’ typical in a round ‘short shaft’ furnace.
https://en.wikipedia.org/wiki/Tatara_(furnace)

(7) We worked a lot with a similar (looking?) limonite ore (‘Lexington Brown’) in the early years of our experiments here. So this estimate is based on those smelts, where typically we used about the same volume of ore - in the ranges of 30 - 35 kg total.
Please remember that is only based on the images - there is no actual data provided!

(8) A very important thing to remember. The camera sees heat colours differently than your eye! Generally, this is an amount equal to ‘one temperature grade’, so when you see orange on film, the actual heat colour is into the reds. A video seen as red is actually dropped at best into the ‘critical’ (below forgeable) range.
This is seen most clearly during the sequence where compaction is being attempted. The iron here is obviously well below actual forging temperatures.

(9) Again intended as a very rough measurement (only!) The solidification temperature of any slag is greatly modified by its iron content. This aspect is often intentionally modified (addition of either more silica via sand or iron oxide via hammer scale) by the most experienced iron makers.
I freely admit that slag chemistry is certainly my worst area of understanding.

(10) Think about slag containing metal particles, running through a sponge (that initial lacy bloom mass). As the slag runs through, it will leave bits of metal behind, slowly filling all the gaps.
( No - this is not exactly how it works, but more take the concept.)

(11) I did do a complete smelt by myself - once. Key here is *once*. And I had an electric blower for air.  (see : Redemption Bloom )

Friday, January 10, 2020

‘Last to Sea’

Elora Sculpture Project - 2020  

(modified from my submission)

A group of ocean creatures are confined within the circle of a plastic fishing net, ‘drowned’ by clear plastic water bottles. Can they be more than glimpsed through that mass of human waste? These are species with ancient lineages, all have have survived through previous mass extinctions. But look! All these are now pushed to the brink of destruction, directly through human activities.

 

This piece owes its genesis from my ongoing (and increasing) concern about human impact on world climate, and what is most certainly the sixth great mass extinction, this time caused directly by our actions. (1) There is a clear connection to ‘Legacy’ (2018), and the ongoing local concern in Wellington County over water bottling. The title is a riff on ‘Last Chance to See’ - a BBC produced radio and later television series profiling endangered species.

The overall form of the piece came from a section of nylon net from the commercial fishery I picked up beach combing on my last trip to Newfoundland (in 2017).
I have several long standing sculptural series, inspired by undersea and ancient life (‘Songs of Distant Oceans’ ). A first time trip to Cuba in 2019 (2), and recent trip to the Ripley’s Aquarium also started me thinking about aquatic life - and especially the impact of human generated plastics.

As I started researching individual creatures, I was actually shocked to find the number of truly ancient species that were on the ‘Endangered’ list, some close to Extinction :

a) ’Tiny Fishes’ (3) - represented by a school grouping, cut from stainless steel sheet and without much detailing. Intended as a reflection of the collapse of the Fishery, how larger species have be hunted beyond viability, so only smaller and smaller fish remain (and are in turn harvested out).
b) Sharks - represented by a larger sculpture ( about 3 feet), made of a series of formed and welded pieces. I was surprised to find so many shark species Endangered (including amazingly the Great White!). Modern types unchanged 200 million years, through 2 Extinction Events.
c) Horseshoe Crabs - formed from several pieces, with a long forged tail (about 2 feet total). Unchanged 450 million years, through 5 Extinction Events (!!).
d) Abalone - forged from a single plate, (about 10 inches). Several types off North American almost extinct through overfishing. Unchanged for 70 million years, through 1 Extinction Event (the ‘youngest’ type portrayed).
e) Sea Turtles - represented by an empty shell, composed of a set of formed and welded together plates.  Of 7 modern types, fully 5 are on the Endangered list. 110 million years (modern species), through 1 Extinction Event.
f & g) Corals - forged from a combination of pipe and solid bar. Shown as Staghorn and Elkhorn, both Endangered. 240 million years for these types, through 2 Extinction Events.
I may also add a couple of more ‘fantastic’ creatures (thinking coral like animals), as a suggestion of life now unknown in the depths - destroyed before ever being known.

I wanted to step back from the more conceptual work of past contributions, which turned out to present mechanical problems in the construction that I was unhappy with. Instead of one large complex (moving) structure, the idea here was to combine a number of smaller objects, using proven techniques on each. In this way, each individual sculpture would prove less important than the setting impact of the entire grouping. (Any one object, if ‘failed’, could be replaced or eliminated without effecting the whole.) Interested public would be able to purchase any of the individual small sculptures - or the entire installation.

Construction :
- Total Height = 3 feet above base / Total width = 4 feet.
- A support frame of heavy angle iron (1 1/2 x 3/16) is overlaid with a base grid of wire grid.
- This holds a layer of thin (2 - 3”) irregular limestone slabs.
- The individual sculptures are either pinned to the slabs or secured to the grid through the gaps between stones.
- The section plastic fishing net is secured through an upper ring of steel rod (3/8 round) - which in turn is held in place by a series of vertical rods (spaced every two feet).
- The main fabrication technique used for the individual sculptures is torch cut heavy plate (1/8 thick), which is then hot forged to 3D curves. Fine details of additional methods will depend on the specific creature forms.  All are left in the ‘fire scale’ finish, which will be intended to rust with time.
- The water bottles will have labels removed, and caps retained (to stop water gathering / mosquitoes!) Ideally these will be a simple loose pile, filling the enclosure. It may prove, however, that this large number will obscure the sculptural forms. If this proves the case, a single layer of bottles will be attached to the sides of the netting, with a number fixed together to form a top plate and suspended from the upper metal ring.
- It is expected the nature of the work, already featuring ‘trash’, may end up collecting additional publicly added refuse. I do not consider this a problem, if anything, this enforces the spirit of the message.


Note: I fully realise that most of the links cited here are hardly the most rigorous, mainly being popular culture vs scientific research types. 
Honestly, I don't consider this fundamentally important to understanding the point.

1) My second submission in 2019 (and although not chosen, the one I personally liked better) was 'Last to See' - a series of concrete slabs with enclosed forged pieces representing 'fossils'. One slab representing the sequence of the five earlier known mass extinction events. Today's Holocene / Anthropocene Extinction makes the sixth.

2) Beach combing has always been real enjoyment for me.
On my January 2019 trip to Boca de Camarioca (east of Havana), one of my real 'finds' was the long sun bleached skull of a sea turtle. This measures 7 1/2 long by 4 inches wide - obviously from a fairly large (and long dead) animal (likely a Logerhead?). My best guess, given how close I found the skull to where local fishermen tied up their boats, is that this was likely killed for the meat. As this was a beach find, not in any way apparently linked to the tourist trade, I did not feel evil keeping it. (Admittedly, I was a lot cautious packing it back home to Canada.)

3) A direct reference to Stan Rogers : 'Tiny Fish for Japan'
My first trip out to Northern Newfoundland was in 1995. Two years after the closing of the Cod Fishery, people were still in a state of shock. Over the years I have returned a number of times to L'Anse aux Meadows. And watch those once fishing cod turn to crab, then turn to shrimp, then to previously undesirable species. (This including 're-branding' types with new, more pleasant names.)
Morning coffee conversations with two marine biologists, billeted at the same B & B in 1996, suggested the following : The total mass of fish in the local oceans was not changing that much. But the larger, top end types were being eliminated, with smaller and smaller fish coming to dominate the total.

An added personal note :

Remember 'Sea Hunt' ?? I sure do! As a kid in the early 60's, I was glued to the TV for every episode. I remember making my own 'tanks' out of paper towel centres, crawling over the living room couch and floor. Almost as soon as I learned to swim, I had a face mask. One of the enduring gifts from my soon to depart father was being taught how to skin dive - I still own my first 'real' snorkel (a US Divers model from the late 1960's).
Although the rivers and lakes around Peterborough, Ontario where I grew up were hardly the warm and crystal clear Florida ocean of my imagination, I have spent far more time under the water, than on it...

If you needed a sobering, science based view : watch 'Ocean Blue' with Silvia Earle

Wednesday, January 01, 2020

Triumpth and Tyranny of the Tiny Screen


‘ There are rules that determine the reaction to emerging technologies : (a)


 ‘ 1) Anything that is in your world when you are born, is normal and ordinary, and just a natural part of the way things work. (b)


‘ 2) Anything that that is invented in the first third of your life span, is new and exciting and revolutionary. (c)



‘ 3) Anything that is invented once you are middle aged, is against the natural order of things.

(paraphrased from 'Hitchhiker’s Guide to the Galaxy - Fit 026', BBC radio version, by Douglas Adams) 

 Now, the raw speed of technological change has itself been exponentially accelerating over my life time. This is so well understood, that ‘Future Shock’ (defined by Alvin Toffler in 1970) hardly exists as a concept any more.
 If anything, the concern I see looming in a current generation is almost the exact opposite. That current conditions might actually result in the decline of rapid change, create some kind of reversal back to a slower pace and reduced accumulation of individual material wealth.


 But here is the first point of this commentary :
- In 2000, roughly 15 million of population of 30 million in Canada had internet access - 50%.
- For 2019, the total is roughly 96% of all Canadians have internet access (34.5 of 38 million). (1)
- Today, 78 % of those people are using a smart phone to access the internet. (2)

But, increasingly, it has become clear that more and more (younger) adults are using tiny cell phone screens as their portal to the internet. And that tiny portal is coming to dominate their entire view of the wider world in all aspects. (3)


 Especially over the last (2019) year, I increasingly receive, if not the majority, of e-mails about the training programs I offer, that look like this :

 ‘ what courses do u offer and what r dates ‘ 
sent from my iPhone 

 Now, if you only used your phone for the internet, what you would get is the intentionally, greatly reduced, for tiny phone screens, short, overview. Which would look like this (4) :
 First View - ‘Training’
Scrolling down - ‘Go on for Details’ section
Hard to read? Turn the screen sideways. 

 Eventually, if you keep scrolling even further down, you will get to a hot link that allows you to send an e-mail to me. This ‘mobile’ version is purposefully mainly composed of images - each image has another hot link available to a specific course description on the main (larger format) web site.
 See all the hot links at the bottom? Same thing (goes to details on that course on the main site). You have to pass a total of SEVENTEEN hot links to the main site, all of which would provide detailed information, to get to the spot where you see my e-mail address - when your portal is a phone.


 Here is the analysis - the second point :

 I’m going to suggest, at this point in time (2020), calling that thing many of you are carrying around a ‘phone’ is disingenuous. (5)


 Remember these? It was half the size of a loaf of bread in 1966.
Ok, your Apple iPhone 11 (current model) does not provide remote scanning for life forms, or more than limited scientific sample analysis. It does however fit in your pocket.
 It does do the following that the Original Series Tricorder did :
- GPS
- three-axis gyro
- Accelerometer
- Proximity sensor
- ambient light sensor
- barometer
- view video (via a 5.8 inch screen, the tricorder has about a 2 1/2 inch)
- audio (no stereo or headphone jack on the tricorder)
- remote connection (although the tricorder was limited to computer interface)

 What your phone has that the tricorder did not :
- touch activated screen
- WiFi (no internet in the 1960’s!)
- Bluetooth system (large number of possible connected devices)
- Siri AI assistant - still camera (12 mpx)
- video camera (HD @ 60 fps, stereo sound)
- camera / video lighting
- water resistance (to 4 m)
- video calling
- And then there are all those applications. Which can add thousands of individual functions that the tricorder never dreamed of.

oh - yea, you also have a mobile phone.

 Ok - wonderful. All that power in your pocket (for a mere $1000 US).
What are you actually using it for?
 - Endless, almost constant (basically meaningless) ’small talk’
- Text Messaging
- more of the same drivel.
- Snap chat - see above via another pipeline
- Instagram, taking endless photographs of yourself doing … well, pretty much the visual form of the same mindless activities. (Your lunch. You getting on the bus…) - - playing games

Yes - you can cruise the internet!
Attempting to view information, presented for viewing on a full sized (typically a 15 inch or more) screen. Next time you use a computer, lay your phone up against the monitor. See the problem?

A generation where the ‘Medium is the Message’.
And the Message is reduced to 140 characters. Someone else’s heavily modified image, taken completely without any context.

A 3 x 5 inch window into a full sized 360 degree world.


 1) Statistic: Number of internet users in Canada from 2000 to 2019 (in millions) | Statista
Find more statistics at Statista

 2) Importantly to this commentary : Among adult users, 88 % are also using desk / lap top portals. (honestly, I suspect this reflects ‘work’ vs ‘home’ use). The main Wareham Forge web site pages also have an ‘e-mail me’ hot link. Again well below all the details are provided. But I’ve built in a way to tell which comes just from phones.
 3) I have commented about this before : ‘About a Phone’ - December 28, 2018
 4) Set up to use an iPhone screen - shown life sized. Those screen shots captured using the Mobile Phone Emulator by Cowemo
 5) There is definite irony here. If you are actually reading this, I am almost certain you will be using a full sized screen, at the least a 13 - 15 inch lap top. As a blog posting, I suspect this commentary would be almost impossible to read on a tiny phone screen. The fact that this is appearing via a ‘blog’ itself, represents what is certainly moving to a ‘dated’ communications method. As a system, blogs started roughly 2000 (This blog dates to 2006).
Statistics in 2019 (from the USA, unfortunately):
- there are 31 million active blogs (at least one post per month)
- 70% of blog owners give $$ as the reason they actively blog
- The current ‘ideal’ length for a blog is given as 2500 words, with a reading time of 7 minutes. (This commentary comes in at roughly 1500 words btw)
- Significantly, this attention span is seen as sharply dropping, year by year.
Source : https://firstsiteguide.com/blogging-stats/ 
Note that the balance there leans to economic performance data
  
Images mostly stolen outright from internet sources - without any author citations. 

Some images are selected to reflect my own Life Frame :
 a) 1955, the year I was born. The DUCE ‘commercial’ computer, used for science and engineering, of which a total of 30 were built. It had 1.5 KILO-byte RAM https://en.wikipedia.org/wiki/English_Electric_DEUCE (Note that Sputnik 1 was launched on Oct 4 that year, I was born one month later, on November 3.)
 b) 1960, The Nixon / Kennedy Debate, on black and white television. As a young kid, my family had a floor console tv from about that date, about the size of a contemporary dish washer. Colour tv was not introduced into Canada until 1966. My parents divorced in 1967, and the family fell on hard economic times for the rest of the years after. We actually only would have tv at home on and off - as individual vacuum tubes failed in what was increasingly an ‘antique’, it often was my paper route earnings that purchased replacements. (One of my earliest ‘events’ memories is the death of John F. Kennedy - but not the Cuban Missile Crisis.)
 c) Apple Macintosh - 1985, 512 KILO-byte RAM, the first ‘all in one’ home computer with the graphic interface now standard for all computers. My first computer, purchased second hand, about 1988. This had an external 20 MB hard drive. (I still have this working machine, with all the original software - on 3.5 floppy disks.)

I currently own :
- Desk Top - Mac Mini / 8 GB RAM / 120 GB drive / 2014 (to OS 10.10.5) Lap Top
- MacBook Pro 3.1 - 15” / 2 GB RAM / 120 GB / 2007 (OS 10.6.8) purchased second hand. Tablet
- iPad Mini / 1 GB RAM / 16 GB drive / 2013 (iOS 9.3.5)
- Cell Phone - Alcatel 460T / 0.5 GB RAM / 2 GB drive / 2016 (Android 4.4.2) This my first ’smart’ phone, although I have the internet data features turned OFF. (BTW : My cell phone is almost always OFF - unless I am traveling.)
 

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

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