Friday, May 27, 2011

Great Northern Medieval Fayre -



I will be demonstrating this weekend at this local event:


The event web site : www.medievalfayre.com

From the 'Living in a Medieval Village' part of the event web site:

Metalsmiths

medieval blacksmith at workThe metalsmith, sometimes called blacksmith, had to first make his tools before he could make metal parts such as horseshoes, nails and door hinges. A blacksmith was named because he was a 'smith' who worked in the "black" metal, namely iron. The "white" metals were tin, silver or gold.

It could take a smith as much as a year to make a full suit of armour for a Knight. If everything didn't fit just right, it could be dangerous.

The Medieval Blacksmith made a huge variety of items and objects which included:
• Medieval Weapons including swords, daggers, lances, arrow heads etc.
• Siege Weapons
• Medieval Armor and shields
• Tools
• Nails
• Church and Castle Doors - hinges, locks and keys
• Instruments of torture and chains
• Household objects including knives, light fittings, pokers etc.
• Ornaments, Jewelry & Decorative Objects

I will be working the reconstructed Norse sand table forge seen above, plus have a display of tools, domestic objects and weapons from the Viking Age :

Education Days - Thursday & Friday : 10 A - 3 P
Festival Days - Saturday & Sunday : 10 A - 4 P

No, I did not write the descriptive text above!

AFTER the event:

It rained. And it poured. And the field was mud - where it was not standing water.
But the kids came and were interested, the sun came out for a couple of hours into the afternoon Sunday so at least the canvas was packed up dry.



Tuesday, May 24, 2011

a new take on Debt Slavery



I was recently contacted by Barry Pettit (of Pettit Integrated Solutions ) about a one day filming session here at the Wareham Forge.

Barry had a project underway to produce an educational video for a large Christian organization in the USA, one with a predominately Black congregation. Normally I would shy away from that kind of situation, but it was clear that this group was also quite concerned about improving peoples 'here and now' as well as their hereafter.

Not surprising when you think about it, people of African American decent make up a very disportionate percentage of working poor in the United States. There is a clear link to lower education levels, lower overall physical health and poor general living conditions. It may be hard to aim at a specific link in that overall chain, but it is certain that these factors relate to each other.

With recent economic events in America, the Church organization decided to target one very clear problem : that of credit card and other debts. Small short term gain for crushing long term losses and restrictions. Borrow a dollar now (often to purchase feel good luxuries) and find you end up bound to the banks.

They wanted to make a very clear and dramatic parallel between modern debt - and historic slavery in America.


Barry's concept was to show people, often elegantly dressed, trapped in a set of arm shackles as they recounted their personal stories of debt. This is an extremely powerful and highly personal image for that target community.
As a way of introducing the concept of modern 'debt slavery', Barry wanted to film a series of close ups of the actual forging of the shackles. The tight views of the individual steps in producing the object would not be clear at first. It might not be till the end of the forging process that the true nature of the object would be clear.

As forged object, this set of simple shackles are not complex. The frames are forged from 3/8 x 1 1/2 flat stock.
These are the steps we filmed:
1) Forging down a 1 x 1 stock bar into the starting 3/8 x 1 1/2 flat
2) Rounding off the rectangular end
3) Hot punching then drifting the holes
4) Hot cutting a section to length
6) Bending the end to a 60 degree tab
7) Forming the curve
(Those steps repeated a total of eight times to form the 4 half shackle segments)
8) Apply a makers mark ('branding')
9) Adjust the end tabs flat
10) Adjust the half sections to fit each other
11) Form a pair of small rings
12) Re-profile about 18 inches of commercial heavy chain by flattening end links
(assemble the finished parts into the complete shackles)

Barry proved excellent to work with. He allowed the work to proceed as it actually would - no 'fake' overheating or oil on the anvil set ups. The many repeats of the individual steps allowed him to both observe the individual steps, but also easily get several takes from different angles of each process in the series.

He showed me some of the recorded sequences as the day progressed. What a difference a professional level video camera makes!

Although Barry's original interest was just in filming the process, I suggested that the small amount of extra time involved in finishing a complete object was certainly worth doing. I was imagining the finished documentary in presentation, and how powerful it would be for a presenter to be able to hold up the actual shackles before the target audience.

Saturday, May 21, 2011

Will YOU be 'Raptured'...

... and if so, can I have your stuff?

Too funny not to repeat!


Stolen without permission from 'Peas & Cougars'
Most of you have probably heard that the rapture is supposedly happening this Saturday, May 21st (“the Bible guarantees it!”). So you’re probably wondering, Will I be raptured? Do I need to find care for my pets? Never fear, I’ve created a flowchart that will answer any doubt you may have.



(added 'Rapture Day')

In case you were wondering why your annoying neighbours were still there when you woke up this morning, I hear the 'official' departure time is 6 PM EST...

But someone threw this up on Facebook this morning (it sure suits *my* sense of humour!)

Tuesday, May 17, 2011

How Hot?

To set the record straight - these are some actual temperatures recorded inside a *working* bloomery furnace:

This is what we got in terms of hard numbers off our last experimental smelt - at the Haffenreffer Museum during the program ran for students at Brown University. (a description on an earlier posting)

The furnace was a standard 'Norse Short Shaft' and was built with a series of small holes down the back side of the cylinder. This put these holes at 90 degrees to the placement of the tuyere. So effectively these could measure the middle of the furnace.
The holes were placed every 10 cm, started from the top of the furnace down. This put the lowest hole at roughly tuyere level.
Measurements were made using a digital pyrometer. The thermocouple wire was inserted into each hole in turn.
Only three sets of readings were possible. There was an equipment failure, caused by the student who installed a fresh battery not correctly closing the case of the instrument. The first set of measurements was made at a point where the charcoal column had yet to fully ignite, so do not represent true working temperatures.
The other two sets of measurements are at roughly the point where there was a full ignition of the reduction column, and at a point 30 minutes after that. It should be noted that we were still establishing the correct balance of air flow against consumption rate (which is also in effect establishing the correct internal furnace temperatures). The ideal situation would be to produce a complete set of temperature readings over the whole progress of a working smelt.


The table was created by Ian Brownstein, who took the measurements on smelt day.

Wednesday, May 11, 2011

Etching on Celtic Iron Age Mirrors?

An answer / commentary about historic etching methods, and my own past work, which came in with today's e-mail dump:
... was just debating about making my version of an iron age mirror then I found the mirrors you have made... was just wondering if you could tell me how you went about etching the pattern on the back of your mirror, I'd like to do it using iron age techniques is that how you did it? I have read that they may have covered the mirror head in wax then scratched out the pattern but I don't know what solution they used for the etching. what technique did you use?

Aaron - Suffolk in England

First, remember that those hand mirrors I show on the web site are at best 'inspired by' ancient artifact, but for a number of reasons can not really be said to be anything but *modern* interpretations! (Thanks for liking them though.)

The actual Celtic Iron Age artifact that inspired this specific design would have been *engraved*, not acid etched. A fine bladed tool (like a small chisel) would have been used to either scratch or cut away a thin channel into the bronze surface. There may have been some kind of ink rubbed into the pattern to accent it, but with the age of so many of these artifacts, its hard to be certain.


Image from www.celticmirrors.org
This site has descriptions and images of a large group of Celtic bronze hand mirrors.

I had done a considerable amount of work with acid etching as a decorative technique back in the 80's. This actually was an application based on what I had learned print making in college.

'Mortreath's Mirror' - shaped and etched brass, early 1980's

Bad news is that as a *historic* technique, the earliest use of true acid etching to produce decorative designs can only be traced back to the 1300's. The earliest objects I had been able to find using etching to make patterns on their surfaces were on the blades of pikes and halberds from Italy. These had used bees wax as a solid surface resist, through which a needle had scratched to expose the bare metal. The etching process produced simple line designs. The technique became more common into the Renaissance.


'A German etched halberd from the late 16th century'
(image from Christies Auction House)

The problem lies with the creation / discovery of actual chemical acids. There is certainly a connection with early Alchemy (which is how many of the discoveries that underlay modern chemistry came about). Before the Middle Ages proper, the only acids available were organic based ones - basically vinegars. Although those organic acids could certainly discolour metals, they were not active enough to usefully cut away at metal in the way required for creation of durable decorative patterning.

My base method on my own work is to use a liquid tar resist, painted on as fine lines and larger areas. When the resist drys, then fine detail can be scratched in with a needle probe. I have used a number of different acids in the past, based on availability of the chemicals and solutions suited to specific metals.

'Dea's Knife' - etched carbon steel blade, etched German Silver hilt and scabbard - 1983
A general description on acid etch method can be found on an earlier blog post.

The main exception to this may be the case with Northern European pattern welded blades (recently also called 'composite twisted core'). Some of the individual artifacts have extremely complex sets of twisted and straight sections to the twisting, the sword from Sutton Hoo being the most elaborate example. Its hard to imagine there would not have been some attempt to accentuate such difficult and careful craftsmanship. Although immersion in vinegar would certainly stain the layers to highlight them, this would be at best a surface discolouration and not a true acid etch for depth.

Modern practice for finishing layered steel blades is to use various acid solutions to expose the fine lines of the layers created in the forging and finishing. As different metals will respond differently to both the same, and also differing, acids, often more than one acid bath may be used.

'Pattern Welded Kitchen Knife' - layered steels, 1996

More information (and samples) of my past work with layered steel blades can be found on :
Bladesmithing from the Wareham Forge
Gallery of past Bladesmithing work

Thursday, May 05, 2011

Peterson Fence - Installed




I had been approached back at the beginning of the year by my friends Neil and Karen Peterson about a project to extend the height of the fence around their yard.


This is the reason why.
(image by Karen Peterson)

The existing fence was an older plank construction. Individual 4 x 4 fence posts were set roughly eight feet apart. Individual sections had a low curve towards the centre, rising about eight inches above the post height.


The design problem was how to extend the line of the fence to keep the energetic Thoka inside the yard. The Petersons wanted to keep the open, 'friendly' line and height of the existing fence. The solution I proposed was using a set of tendril like brackets to support a rail made of one inch diameter pipe above each of the curved board sections.

There are considerable details on the design of these elements, and a photo essay on their construction, in an earlier blog posting : the Peterson Fence Project (March 6)

This week saw me (finally!) get the completed project installed. (To my defence, poor spring weather delayed both paint drying and possible outdoor working date.)


The 62 individual support brackets laid out for installing.

Each of the 15 fence sections had four brackets to support the pipe. These were designed with half wrapping to the right, half to the left. No two pieces are identical. Each piece was roughly 30 inches long when completed. Perhaps a bit over strength, the starting stock was 1/4 x 1 1/2 inch flat. The paint colour was a custom mixed dark brown.


Detail of brackets at the front corner, view up the street.

The separate units were designed to have a gap over the top of each of the fence posts. This was primarily to allow the individual sections of fencing to flex. I made a spot decision not to set the line of the rails at absolutely level. Instead the rails echo the top lines of the individual fence panels (measured at the attachment to the fence posts at either end. This is because the line of the fencing itself is not level, but instead follows the pitch of both the driveway (down from house to street) and along the side walk (running upwards away from the driveway).


View of the driveway side of the installed rails.

You can also see that the position of the rail is about 12 inches above the low point near the fence post, closer to 4 + inches above the topmost height of the cut boards. The brackets are also offset about 4 inches back from the line of the existing fence boards. This combination doubles the effective height of the rails - at least in terms of keeping puppies inside the yard!
 

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

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