Monday, October 31, 2011

Happy Halloween

What is the scariest film you've ever seen?

Well, Alien (1979) if you like things that jump out of the dark at you.

But one of my favourite films of all time is John Carpenter's the Thing (1982)

The film is loosely based on the older 'The Thing from Another World' (1951), itself based on the classic James Campbell novella 'Who Goes There?'
The film has a wonderful atmosphere, crafted from camera, lighting and sound track. Absolutely great special effects, mainly because it was one of the last huge horror films to use actual life sized models rather than digital effects. 

Why does it scare me?

Remember all those times you sat watching some film, and you saw someone flick a light switch, find the lights don't work, and said " Don't go IN there, you idiot!'!
And sure as shit, bozo walks into the dark, and straight into the monster.
Or you watched someone walking * backwards * down the hall, when they * know * there is a crazed maniac with a chainsaw loose in there someplace?
Or they are being chased by a hoard of blood sucking zombies, yet they run past a * shot gun * and instead pick up a golf club?

Ok, a bunch of American scientists in Antartica are kind of attacked by a couple of crazed Norwegians from the only nearby base. Wondering why, they go there, only to find everyone slaughtered, a huge wreck of a space craft uncovered in the ice, an empty coffin sized block of ice - and some very, very bizarre remains. Of * course * they have to haul that back to home base.
Later that night, frantic howling comes from the dog pens.
MacReady (played by Kurt Russell), on hearing the ruckus, hits the fire alarm, and his first command on the way over to the area is 'Get the flame thrower!'

What the Frack??
Who hears a bunch of dogs barking and sends for a flamethrower?
Did the character read the script before hand?
Would that be * your * first impulse?

(If so, you may be one of my close friends, but go with me here, ok?)

Now here's the part that scares me...

It doesn't do them all any damn good.
They all die anyway, mostly horribly.
Other than MacReady and one other, who might actually be alien shape changers themselves at that point anyway (and the end of the film certainly suggests this).

And the kids are scared of Frackin'  ZOMBIES ...

I guess it beats worrying about glowing in the dark during a Nuclear Winter?

Saturday, October 29, 2011

DARC at CanIRON 8 - Smelt Report...

... is finally prepared!

Go to the main Wareham Iron Smelting web site: DARC at CanIRON 8

(Image above by David Daciw)

Monday, October 24, 2011

Measuring the HEAT...

Iron Smelting Furnace Temperatures
Short Shaft over Slag Pit

October 9, 2011 / DARC Smelt Team, Neil Peterson recording

On our last smelt, we set up to record furnace temperatures over the duration of the experiment.

The furnace was our standard short shaft type, roughly 25 cm interior diameter, 70 cm total height.
Walls were clay and straw cobb, about 10 cm thickness.
Fuel was hardwood charcoal (mainly oak) graded to .5 through 2.5 cm diameters.
Air volume via the tuyere (set at 20 cm above base) was roughly 800 litres per minute.

Holes were drilled through the furnace walls at roughly every 10 cm, starting at 10 cm above the interior base.
Measurements were taken using an industrial quality digital pyrometer (HH12B from Omega equipped with standard bare metal type K thermocouples).
The probes were inserted roughly 5 cm beyond the interior surface of the furnace wall.
Measurements were taken roughly every hour over the course of the smelt event.

Because the probes did not reach into the central core of the furnace, there is every possibility that the central furnace temperatures were even higher than what was recorded.
Our thermocoples failed (melted!) at roughly 1350 C. On several recordings, this temperature was reached.

Image : Neil takes readings, early in the smelt

Time Elapsedbasetuyereplus 10plus 20plus 30plus 40top
10 cm20 cm30 cm40 cm50 cm60 cm70 cm
12:06:06 653890749579343
13:051:05 10421335130011451002610
13:501:503281051plus 1350119511891014660
16:324:32 11241265 *909700719

Note : It has been suggested by some theoretical researchers that temperatures above 1200 C are impossible to achieve inside a charcoal fired furnace...

Friday, October 21, 2011

Thanksgiving Smelt - fast overview

'Celtic Iron Age' slag pit furnace
October 9, 2011
DARC smelt team

Showing the initial layout of the 'pit'. A standard 20 L plastic pail was surrounded by dirt, then filled to top with cut willow branches (about 0.5 - 1 cm diameter). Use of concrete blocks would allow for easy excavation after the experiment.

Our standard short shaft furnace is constructed on top of the pit. Clay with straw cobb, 25 cm ID, 70 cm tall. Ceramic tube tuyere (2.5 cm ID), electric blower.

Total time : 5 3/4 hours
Total charcoal : 57.5 kg
Total ore : 48 kg

Slag block as excavated (furnace itself was removed in one piece and retained for further use) There was no actual bloom recovered!

A fragment of the slag block, showing how hot slag had dripped down between the sticks, solidified, the heat converting the wood to charcoal. This from the front side of the furnace, indicating lack of iron (pale green colour). Slag to the rear of the furnace was a black iron rich colour.

The purity of the ore was questionable.
There is a chance some iron may exist trapped inside the slag block. A check with a magnet at the usual location (under the tuyere) did not indicate any however.
It is possible that the existing iron rich slag might be recovered, then utilized in a second smelt attempt.

For now we want to retain the slag block itself as a sample.

The extracted slag block. In this shot the tuyere is located to the upper right, directly above the scale vertical line. The colour shift in the slag from the rear to the front of the furnace is easily seen. There is an extra bulge in the slag about at ground level (the clay furnace sat directly on the loose dirt here.

A full report is in the works!

Saturday, October 08, 2011

Styll 2 - bragging a wee bit...

... they used one of my pieces for the advertising!
That's my piece 'Toxic' in the upper left corner. Created specifically for this exhibit.

I'm up to my neck repairing the Wareham smelting area, and preparing for Sunday's iron smelt. This time it is a 'Celtic' style slag pit furnace. Expect an overview over the next bit...

Saturday, October 01, 2011

Thanksgiving IRON SMELT at Wareham

One of the traditional iron smelt events at Wareham is over Thanksgiving weekend. This is 'Darrell's Smelt' (originally a sad replacement for Early Iron after that event was dropped). The DARC team normally takes part.

Because Thanksgiving is a family day for many, and because some people get involved with the archery stuff in KW also that weekend, Smelt Day is SUNDAY.

The tentative plan for the weekend will be this:

Saturday - Furnace Build and Open workshop (self directed)
Sunday - Smelt Day
Monday - Evaluate and clean up

Vandy and I will be prepared to welcome guests any time after 9 AM.
The primary working day is SUNDAY, for those intending on a one day trip.
As usual, this is a 'limited open' event - please drop me a post back if you are intending on coming up.

Going into 2012, I want to work towards a new furnace type. I have proposed to Goderich Celtic Festival that I undertake a smelting demo at their event next August. This would be a Celtic Iron Age, slag pit type furnace. The style applies to early Danish and Anglo Saxon as well.
The upper portion of the planned furnace is going to be much like our standard types (short shaft, clay cobb construction). I have a wide number of ore types on hand, and have not determined which I may use. (Likely one of the Virginia rock ores, as I have considerable of those materials.)

Any working advice from our friends in England and Denmark, who have worked with these type of furnaces, would be helpful!

VA Glass Bead Experiment 9/10/11

Viking Age Bead Making
September 2011
All made in 'K' furnace (Ribe oval - charcoal fired)

A note to Readers : This was my contribution to a much larger effort, comprising of three furnaces and four bead makers. See Neil Peterson's entire report on the DARC web site.

Furnace Layout
'K' Furnace MeasurementsTheoretical Air Flow
Furnace Details
Showing Air SystemCutting Loading PortAfter Loading Charcoal
Working Port A (used for experiment)Working Port B

Note : open your browser window REAL wide to see the full table!

see below

9-11A.jpgcaneflat oval10.4 E5.6 Ess rod3.7 E
removal2/3 only

9-11B.jpgcaneflat oval9.64.6ss rod3.6
chip in annealer

9-11C.jpgcaneoval12.6 E9.1
removal1/2 onlydraw to one end


9-11D.jpgtesseriflat oval11.55.5iron5.34.7port A

9-11E.jpgtesserioval10.37.2iron3.62.9port A

points both sides


rolled9-11F.jpgtesseribarrel12.412.5iron4.13.5port Aoff floornext daythirdsash coated

9-11Gbluebrownblobcut bars9-11G.jpgtesseribarrel13.711.8iron42.6port A

9-11H.jpgtesserioval9.55.3iron3.12.8port Aoff spoonremovalhalf

9-11Ilight blueblackdots
9-11I.jpgcaneoval13.68.9iron43.5chimneyoff bottom surfacein annealerhalfslightly irregular

9-11J.jpgtesseriround10.69iron3.32.3port & chimneystringer off spoonremoval1/2 only
Definitions of SHAPES indicated above:
Individual Beads Described above :

Bead 9-11 ABead 9-11 B (chipped)Bead 9-11 C (half only retrieved)
Bead 9-11 DBead 9-11 EBead 9-11 F
Bead 9-11 GBead 9-11 HBead 9-11 1(broke later)
Bead 9-11 J (half only retrieved)

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

COPYRIGHT NOTICE - All posted text and images @ Darrell Markewitz.
No duplication, in whole or in part, is permitted without the author's expressed written permission.
For a detailed copyright statement : go HERE