IRON SMELT Experiment Overview

Text Version
V3 T /  2001 - 2008
Date : June 2001
Experiment : 1
Location : L'Anse Aux Meadows NF
Team : Parks Canada Consultants (1)
Furnace : Norse boxed bowl
- stone slab sides, clay sealed, sod backed
- no tap arch
Size : 35 cm x 30 x 50 H (square)
Source : based on LAM (theoretical)
Tuyere : 25 mm ID steel pipe
Placement : 5 cm above floor
- 3 cm in from wall
- angle slightly up
Bellows : standard Norse double chamber
Air : (E) 2 L per stroke
- (E) 120 L per minute
Charcoal : 8 kg broken hardwood
Consumption :
Ore : LAM bog ore - 5 kg (roasted)
Sequence : ore added as one large charge
Duration : about 2 hours (plus preheat)
Result : small slag mass
- some small iron 'prills' (total 100 gm)
- test as high carbon (cast iron)
Notes : a number of basic errors, consider equipment test :
- charcoal allowed to burn down to half way
- ore placed on raft of bark
- air flow not constant (cycles temperature)
- low pressure / poor penetration of air
- sequence too short
Date : May 2002
Experiment : 2 / D1
Location : Wareham ON
Team : DARC (2) + Dr. Kevin Smith
Furnace: Norse boxed bowl
- stone slab sides, clay sealed, sod backed
- no tap arch
Size : 30 cm x 30 x 40 H (square)
Source : based on LAM (theoretical)
Tuyere : 25 mm ID steel pipe
Placement : angle slightly up
Bellows : standard Norse double chamber
Air : (EE) 1.2 L per stroke
- (EE) 120 - 72 L per minute
Charcoal : 22 kg broken hardwood
Consumption :
Ore : St Lunaire bog ore - 6 kg (roasted)
- mix of 2.8 ore / 2.5 scale / .7 sand
Sequence : ore added as three large charges
Duration : about 8 hours (plus preheat)
Result : 2 kg slag mass
- total 4.3 kg magnetic slag recovered
Notes : a number of basic errors
- use of large amount forge scale
- extremely low air volume
- low pressure / poor penetration of air
- air flow not constant (cycles temperature)
Date : June 2003
Experiment : 3 / D2
Location : Wareham ON
Team : DARC
Furnace : Early Medieval Medium Shaft
- cylindrical cob with refractory liner
- tap arch
- fire brick base
Size : 27 cm taper to 24 x 90 H
Source : suggested by Sauder & Williams
Tuyere : 25 mm ID steel pipe
Placement : (E) about 20 cm from base
- about 5 cm in from wall
- angle at 15 down
Bellows: vacuum blower
Air :
Charcoal : (E) 50 kg broken hardwood
Consumption : about 1.5 kg charcoal every 12-15 minutes
Ore : Virginia rock ore - 8 kg (roasted)
Sequence : ore added as 6 x 1.5 kg charges
Duration : about 4 1/2 hours (plus preheat)
Result : - initial liquid slag (faylite) tapped
- burn through crashes sequence
Notes : Generally sequence is closer to correct
- slag bowl forms too high
- slightly reduced air volume
- incorrect tuyere angle

Date: June 2004
Experiment : 4 / D3
Location : Wareham ON
Team : DARC + Mike McCarthy / Mark Pilgrim
Furnace : Norse Boxed Short Shaft
- cylindrical cob backed with stone slab and sand
- no tap arch
Size : 25 cm tapers to 20 x 50 H
Source : suggested by Crew
Tuyere : 25 mm ID steel pipe
Placement : 2 cm from base
- about 5 cm in from wall
- angle at 15 down
Bellows : initial Norse double bag / various
Air : initial 2.2 per stroke / at 130 per minute
/ various
Charcoal : (E) 19 kg broken hardwood
Consumption : about 1.5 kg charcoal every 12-15 minutes
Ore : Virginia rock ore - 7 kg (roasted)
Sequence : ore added as 7 x 1 kg charges
Duration : about 6 hours (plus preheat)
Result : slag masses only
Notes: - Clay slumps during smelter construction
- moves tuyere to incorrect position,
too close to floor and shallow angle. This 'drowns' air flow.
- Air system failures lead to fluctuating temperatures
- Attempt to cut new tuyere unsuccessful
Date : October 2004
Experiment : 5
Location : Cooperstown NY (Early Iron 1)
Team : Michael Mahoney / Millard Wyman
Paul Burdon / Elizabeth Hendrix
Furnace : Norse Short Shaft
- cylindrical cob set in earth trench
- no tap arch
Size : 28 cm x 60 H
Source : suggested by earlier experiments
Tuyere : 25 mm ID steel pipe
Placement : 15 cm from base
- about 3 cm in from wall
- angle at 15 down
Bellows : Norse double bag
Air : 2.2 L per stroke
- at 130 L per minute
Charcoal : 100 L broken hardwood
Consumption : about 6 L charcoal every 15 minutes
Ore: Virginia rock ore - 8 kg (roasted)
Sequence : ore added as 5 x 1.5 kg charges + .5 reduction
Duration : about 4 hours (plus preheat)
Result : 'pre bloom mass'
Notes : Air cut during operator changes and short smelter repairs
- Generally structure successful
- Air flow still low
- Longer sequence required to develop larger bloom
Date : October 2004
Experiment : 6 / D4
Location : Wareham ON
Team : DARC
Furnace : Econo Norse
- firebrick backed with sand set in earth trench
- no tap arch
Size : 30 cm x 70 H
Source : suggested by earlier experiments
Tuyere : 25 mm ID steel pipe
Placement : 20 cm from base
- about 3 cm in from wall
- angle at 20 down
Bellows : vacuum blower
Air : 550 L per minute
Charcoal : 110 L broken hardwood
Consumption : about 6 L charcoal every 12 - 15 minutes
Ore : Virginia rock ore - (EE) 8 kg (roasted)
Sequence : ore added as 8 x 1 kg (E) charges
Duration : about 5 1/2 hours (10 hours total)
Result : 2 kg bloom - high carbon (cast iron)
Yield : EE 25%
Notes : Air cut (electrical problems) at pre-heat only
- Successful creation of small bloom
- Air flow still a bit low
- Longer sequence required to develop larger bloom

Date : February 2005
Experiment : 7
Location : Lexington VA (Smeltfest 05)
Team : Gangue aux Fer (3)
Furnace : Econo Norse
- firebrick backed with sand set on plinth
- tap arch
Size : 25 cm x 60 H
Source : DARC 10/04
Tuyere : 25 mm ID 1/8" formed copper
Placement : 18 cm from base
- about 5 cm in from wall
- angle at 20 down
Bellows : vacuum blower
Air : 815 L per minute
Charcoal : 85 kg broken hardwood
Consumption : about 2 kg charcoal every 10 minutes
Ore : Virginia rock ore - about 35 kg (roasted)
Sequence : ore added about every 10 minutes
as small charges .5 - 2 kg
Duration : about 7 hours (not including preheat)
Result : 6.5 kg bloom - (not tested)
Yield : 18 %
Notes : - Successful creation of mid sized bloom
- tap slag recycled
Date : February 2005
Experiment : 8
Location : Lexington VA (Smeltfest 05)
Team : Vince Petty / Vandy Simpson
Furnace : Econo Norse
- firebrick backed with sand set on plinth
- tap arch
Size : 25 cm x 60 H
Source : DARC 10/04
Tuyere : 25 mm ID 1/8" formed copper
Placement : 18 cm from base
- about 5 cm in from wall
- angle at 20 down
Bellows : vacuum blower
Air : 815 L per minute
Charcoal : 85 kg broken hardwood
Consumption : about 2 kg charcoal every 10 minutes
Ore : Virginia rock ore - 28 kg (roasted)
Sequence : ore added about every 10 minutes
as small charges .5 - 2 kg
Duration : about 7 hours (not including preheat)
Result : 7.5 kg bloom - (not tested)
Yield : 27 %
Notes : - Successful creation of mid sized bloom
- tap slag recycled

Date : May 2005
Experiment : 9
Location : Wareham, ON
Team : OABA / Neil Peterson / John Burton
Furnace : Econo Norse
- firebrick backed with sand, set on plinth
- tap arch
Size: 25 cm x 60 H
Source : DARC 10/04
Tuyere : 25 mm ID schedule 40 pipe
Placement : 20 cm from base
- about 5 cm in from wall
- angle at 20 down
Bellows : electric blowers / rotary hand
Air : inconsistent flow
Charcoal : 67 kg broken hardwood
Consumption : about 2 kg charcoal every 10 minutes
Ore : Stelco taconite - 3 kg (roasted)
Sequence : ore added about every 12 minutes
as small charges .75 - 3 lbs
Duration : about 7 hours (not including preheat)
Result : 9.5 kg bloom - (estimated)
Yield : 45 % E
Notes : - Successful creation of mid sized bloom
- tap slag recycled
Date : June 2005
Experiment : 10 / D5
Location : Wareham, ON
Team : DARC smelt demo team
Furnace : Norse Short Shaft
- clay cob with stone slab support
- tap arch
Size : 25 cm x 60 H
Source : suggested by earlier experiments
Tuyere : 25 mm ID schedule 40 pipe
Placement : 16 cm from base
- about 5 cm in from wall
- angle at 20 down
Bellows : large double bellows / electric blower
Air : 600 l / min (estimated)
Charcoal : 38 kg broken hardwood
Consumption : about 2 kg charcoal every 10 minutes
Ore : Stelco taconite - 9 kg (roasted)
Sequence : ore added in variable sequence (10 - 20 min)
as small charges .75 - 2.25 lbs
Duration : about 7 hours (not including preheat)
Result : 3 kg bloom - (estimated)
Yield : 28 % E
Notes : - Successful creation of historic sized bloom
- extreme hot weather limits use of bellows
Date : September 2005
Experiment : 11 / D6
Location : Annapolois Royal NS
Team : DARC smelt demo team + Mark Pilgrim
Furnace : Norse Short Shaft
- commercial clay cob with stone slab support
- tap arch
Size : 25 cm x 60 H
Source : suggested by earlier experiments
Tuyere : 25 mm ID schedule 40 pipe
Placement : 24 cm from base
- about 5 cm in from wall
- angle at 20 down
Bellows : large double bellows / electric blower
Air : no data
Charcoal : 47 kg broken hardwood
Consumption : about 2 kg charcoal every 10 minutes
Ore : Stelco taconite
-9 kg (roasted)
Sequence : ore added in variable sequence (10 - 20 min)
as small charges .75 - 2.25 lbs
shift to forced air at
Duration : about 7 hours (not including preheat)
Result : cast iron mass
2 kg? no data available on size
Notes : use of high purity taconite means no silica
- use of high temperature clay means no silica
- no silica means no carbon control
- exit valves required on bellows ??
Date : September 2005
Experiment : 12
Location : Copperstown NY (Early Iron 2)
Team : Elizabeth Hendrix / Toby Bashaw
Furnace : Flue Tyle
- commercial tile reinforced with wire
- tap arch
Size : 25 cm square x 60 H
Source : developed by Sauder & Williams
Tuyere : 25 mm ID forged copper
Placement : about 24 cm from base
- 5 cm in from wall
- angle at 20 down
Bellows : electric blower
Air : plus 1000 L/min?
Charcoal : 110 lbs primary sequence / no data for balance*
Consumption : about 5 lbs charcoal every 10 minutes
Ore : Virginia Rock Ore - about 35 lbs *
Sequence : ore added in variable sequence (8 - 12 min)
as small charges .75 - 2.25 lbs
Duration : about 7 1/2 hours * (not including preheat)
Result : Two bloom masses
Secondary at 3.4 KG
Notes : Main smelt sequence abandoned at 6 1/2 hours
Smelt assumed, produced secondary 'salvage bloom'
* no clear records kept for secondary sequence
Date : October 2005
Experiment :13 / D7
Location : Wareham, ON
Team : DARC
Furnace: Norse Short Shaft
- clay cob with stone slab support
- tap arch
Note - reuse of furnace from June 05
Size : 25 cm x 60 H
Source : suggested by earlier experiments
Tuyere : 25 mm ID ceramic kiln support
Placement : 16 cm from base
- about 5 cm in from wall
- angle at 20 down
Bellows : vacuum blower
Air : 600 l / min (estimated)
Charcoal : 79.5 kg broken hardwood
Consumption : about 2 kg charcoal every 10 minutes
Ore : Stelco taconite + Virginia Rock Ore
17 kg (roasted)
Sequence : ore added in variable sequence (7 - 10 min)
as small charges .75 - 2.25 lbs
Duration : about 6 1/4 hours (not including preheat)
Result : 4.3 kg bloom
Yield : 22 %
Notes : - Successful creation of historic sized bloom
- Success in patching and re-firing smelt
Date: February 2006
Experiment: 14
Location: Black Rock Forge, Traverse City MN
Team: (demonstration) Brent Cole, Ken Chambers
Furnace: Econo Norse
firebrick backed with sand set on plinth
tap arch (disassemble to extract)
Size: 25 cm x 60 H
Source: DARC 10/04
Tuyere: 25 mm ceramic tube
Placement: 20 cm from base
about 5 cm in from wall
angle at 22.5 down
Bellows: electric blower
Air: 775 L per minute
Charcoal: 107 kg broken hardwood
Consumption: about 2 kg charcoal every 9 minutes
Ore: Michigan taconite
45.5 kg (roasted)
Sequence: ore added about every 9 minutes
charges range from .45 to 2.2 kg each
Duration: about 7 1/4 hours (not including preheat)
Result: 13.5 kg bloom - good workable iron
Notes: - Successful creation of mid sized bloom
- small amount of tap slag recycled
Date: March 2006
Experiment: 15
Location: Smeltfest - Lexington VI
Team: Dick Sargent (Gangue aux Fer)
Furnace: Norse Medium Shaft - "Yormungand'
clay cob set on plinth
tap arch (bottom extraction)
Size: 35 to 30 cm x 85 H
Source: ongoing research, details suggested by Williams
Tuyere: 25 mm ID ceramic tube
Placement: 15 cm from base
about 6 cm in from wall (wall is angled)
angle at 22.5 down
Bellows: electric blower
Air: 740 l/m
Charcoal: 84 kg broken hardwood
Consumption: about 2 kg charcoal every 7 minutes
Ore: hematite grit (commercial)
45.5 kg
Sequence: ore added about every 7 minutes
increasing from .5 to 2.8 kg
Duration: about 4 3/4 hours (not including preheat)
Result: 22 kg bloom - high carbon 'steel'
Notes: - Successful creation of large carbon rich bloom
- test of spit wood form
- test of commercial hematite blasting grit ore
Date: March 2006
Experiment: 16
Location: Smeltfest - Lexington VI
Team: Dick Sargent (Gangue aux Fer)
Furnace: Norse Short Shaft - "Yormungand'
clay cob set on plinth
tap arch (bottom extraction)
second firing of furnace
Size: 35 to 30 cm x 60 H
Source: ongoing research, details suggested by Williams
Tuyere: 25 mm ID ceramic tube
Placement: 15 cm from base
about 6 cm in from wall (wall is angled)
angle at 22.5 down
Bellows: electric blower
Air: 740 l/m
Charcoal: 68 kg broken hardwood
Consumption: about 2 kg charcoal every 7 minutes
Ore: hematite grit (commercial)
45.5 kg
Sequence: ore added about every 7 minutes
increasing from .5 to 2.8 kg
Duration: about 4 3/4 hours (not including preheat)
Result: 2o kg bloom - high carbon 'steel'
Notes: - Successful creation of large carbon rich bloom
- damaged top of previous smelter removed
- clear duplication of earlier sequence
Date: June 2005
Experiment: 17 / D8
Location: Wareham, ON
Team: DARC - Leaders Dave Cox & Kevin Jarbeau
Furnace: Norse Short Shaft
clay cob half dug into earth bank
small tap arch (top extraction)
Size: 25 cm x 65 H
Source: suggested by earlier experiments
Tuyere: 25 mm ID ceramic tube
Placement: 7 cm from base
about 5 cm in from wall
angle at 22.5 down
Bellows: electric blower
Air: 970* l / min (re-calculated)
Charcoal: 87 kg broken hardwood
Consumption: about 2 kg charcoal every 10 minutes
Ore: Virginia rock ore
18 kg (roasted)
Sequence: ore added in smaller charges for most of smelt
considerable re-cycle of tap slag
Duration: about 8 hours (not including preheat)
Result: 1.5 kg bloom - cast iron
Notes: - first smelt controlled by Dave and Kevin
- slow addition of ore resulted in excess carbon
Date: September 2006
Experiment: 18 / D9
Location: Bonfield ON (Baron's Howe SCA)
Team: DARC - Nick West (with labour from observers)
Furnace: Norse Short Shaft
clay cob with stone slab support
small tap arch
Size: 28 to 18 cm x 60 H
Source: suggested by earlier experiments
Tuyere: 25 mm ID ceramic tube
Placement: no information on base
about 5 cm in from wall
angle at 22.5 down
Bellows: large double bellows
Air: no data
Charcoal: 59 kg broken hardwood
Consumption: about 2 kg charcoal every 15 minutes
Ore: Virginia rock ore
10.5 kg (roasted)
Sequence: ore added in variable sequence (10 - 20 min)
as small charges .75 - 2.25 lbs
Duration: about 6 1/4 hours (not including preheat)
Result: small cast iron mass - no data available on size
Notes: demonstration smelt with high audience content
Irregular bellows control from many operators
smelter set up to replicate LAM arrangement
Date: October 2006
Experiment: 19
Location: Peter's Valley NJ - Early Iron 3
Team: none (demonstration smelt)
Furnace: Small diameter Norse short shaft - "Loki'
clay cob set
small tap arch (top extraction)
Size: 20 cm x 65 H
Source: ongoing research
Tuyere: 25 mm ID ceramic tube
Placement: 7 cm from base
about 5 cm in from wall
angle at 22.5 down
Bellows: electric blower
Air: 700 * l/m (based on recalculated rates)
Charcoal: 36 kg broken hardwood
Consumption: about 2 kg charcoal every 14 minutes
considerable variation (from 9 - 20 min)
Ore: Minden Bog
8.9 kg
Sequence: ore added about every 14 minutes (see above)
increasing from .5 to 1 kg
Duration: about 4 3/4 hours (not including preheat)
Result: .7 kg small lumps of clean cast iron
Notes: - Successful test of small diameter furnace
- test of (questionable) Minden 'ooze'
Date: October 2006
Experiment: 20
Location: Peter's Valley NJ - Early Iron 3
Team: Dick Sargent (Gangue aux Fer)
Furnace: Flue Tyle
standard clay tile set on block plinth
bottom extraction
Size: 28 cm x 60 H
Source: Developed by Sauder & Williams
Tuyere: 25 mm ID ceramic tube
Placement: 15 cm from base (?)
about 3 cm in from wall
angle at 20 down
Bellows: Rock Bridge blower
Air: approx 1000 l/m E
Charcoal: 60 kg broken charcoal
Consumption: about 2 kg charcoal every 8 minutes
Ore: Virginia rock ore
45.5 kg (roasted)
Sequence: started at 1.7 increasing to 2.4 kg
Duration: about 5 hours (plus preheat)
Result: 8.2 kg dense bloom of workable iron
Notes: - use of large charges suggested by McCarthy
- furnace ran hot and predictably
- 1/3 forged into Norse reproduction anvil
Date: November 2006
Experiment: 22 / D10
Location: Wareham, ON
Team: DARC
Furnace: Norse Short / Medium Shaft
clay cob half dug into earth bank (reuse of 6/06)
small tap arch (top extraction)
Size: 25 cm x 65 H
metal cylinder extends top 30 cm
Source: suggested by earlier experiments
Tuyere: 25 mm ID ceramic tube
Placement: 10 cm from base (light ash only)
about 5 cm in from wall
angle at 22.5 down
Bellows: electric blower
Air: 1060* l / min (re-calculated)
Charcoal: 29 kg broken hardwood
Consumption: about 2 kg charcoal every 6 minutes
Ore: Virginia rock ore
21 kg (roasted)
Sequence: all charges at 2 kg each
Duration: about 2.3 hours (not including preheat)
Result: large volume of high iron content slag
no recognizable bloom
Notes: - attempt to duplicate 'fast charge' method
- reuse of earlier cobb smelter
- no solid base lowers material below sinter zone
Date: November 2006
Experiment: 22
Location: Wareham, ON
Team: none
Furnace: Norse Short / Medium Shaft
clay cob half dug into earth bank (reuse of 6/06)
small tap arch (top planned, bottom used)
Size: 25 cm x 65 H
metal cylinder extends top 30 cm
Source: suggested by earlier experiments
Tuyere: 25 mm ID ceramic tube
Placement: 10 cm from base
about 5 cm in from wall
angle at 22.5 down
Bellows: electric blower
Air: 1060* l / min (re-calculated)
Charcoal: 51 kg broken hardwood
Consumption: about 2 kg charcoal every 6 minutes
Ore: Virginia rock ore plus gangue from previous smelt
8.8 kg (roasted) plus 10.2 kg
Sequence: ore added first as 1.4 kg each 6 minutes
gangue added last as 1.1 kg each 7 minutes
Duration: about 2.3 hours (not including preheat)
Result: 6.8 kg dense workable iron
Notes: - 'Redemption Smelt' to re-smelt gangue material
- attempt to duplicate 'fast charge' method
- reuse of earlier cobb smelter
Date: June 2007
Experiment: 23
Location: Wareham ON
Team: (course) Steve Mikaff, Colin Paddin
Furnace: Econo Norse
firebrick backed with sand set on plinth
tap arch (disassemble to extract)
Size: 25 cm x 60 H
Source: DARC 10/04
Tuyere: 25 mm ceramic tube
Placement: 23 cm from base
about 5 cm in from wall
angle at 22.5 down
Bellows: electric blower
Air: 800 L per minute
Charcoal: 63.5 kg broken hardwood
Consumption: about 2 kg charcoal every 8 minutes
Ore: commercial hematite grit
22.5 kg (roasted)
Sequence: ore added about every 8 - 3 minutes
charges range from .45 to 1.5 kg each
Duration: about 4 hours (not including preheat)
Result: 12.5 kg bloom - good workable medium carbon
Notes: - textbook smelt as course
Date: June 2007
Experiment: 24 / D11
Location: Wareham ON
Team: Neil Peterson, Darrell Markewitz, Ron Ross
Furnace: short shaft (half banked)
clay cobb
tap arch (top extraction)
Size: 22.5 cm x 60 (+ 15 collar) H
Source: ongoing research,
Tuyere: 25 mm ID ceramic tube
Placement: 14 cm from base
about 5cm in from wall (wall is angled)
angle at 15 down
Bellows: electric blower
Air: 900 l/m
Charcoal: 56.5 kg broken hardwood
Consumption: about 2 kg charcoal every 7 minutes
Ore: Virginia Rock (poor)
23.3 kg
Sequence: ore added about every 8 minutes
increasing from .45
Duration: about 5 hours (not including preheat)
Result: .9 kg bloom – good workable iron
Notes: - low yield expected from poor ore
first phase of 'hot swap' double smelt
Date: June 2007
Experiment: 25 / D12
Location: Wareham ON
Team: Dave Cox, Kevin Jarbeau Ken Cook
Furnace: short shaft (half banked)
clay cobb
tap arch (top extraction)
Size: 22.5 cm x 60 (+ 15 collar) H
Source: ongoing research,
Tuyere: 25 mm ID ceramic tube
Placement: 14 cm from base
about 5cm in from wall (wall is angled)
angle at 15 down
Bellows: electric blower
Air: 900 l/m
Charcoal: 42 kg broken hardwood
Consumption: about 2 kg charcoal every 9 minutes
Ore: 50/50 hematite grit + Virginia Rock (poor)
23.9 kg
Sequence: ore added about every 8 minutes
increasing from .45 – 1.5 kg
Duration: about 3.25 hours (no preheat)
Result: 3.1 kg bloom – good workable iron
Notes: - lower yield expected from poor ore
second phase of 'hot swap' double smelt
significant burn through with extended smelt time
Date: October 2007
Experiment: 26
Location: Wareham, ON
Team: Darrell Markewitz, Neil Peterson
Furnace: Norse Short Shaft
clay slabs half dug into earth bank with stone above tuyere
small tap arch (top extraction)
Size: 20 x 24 cm x 62 H
Source: suggested by LAM
Tuyere: 25 mm ID ceramic tube
Placement: 15 cm from base (no set base)
about 5 cm in from wall
angle at 22.5 down
Bellows: electric blower
Air: start at about 500 – finish at 800 l / min
Charcoal: 54 kg broken hardwood
Consumption: about 2 kg charcoal every 7 minutes
Ore: Stelco taconite
12.3 kg (roasted)
Sequence: ore added in smaller charges for most of smelt
considerable re-cycle of tap slag
Duration: about 5:45 hours (not including 1:30 preheat)
Result: 6 kg bloom – workable iron
Notes: - test of stone plate above tuyere
- test of simple 'blow hole' set up
- start with lower air delivery
Date: October 2007
Experiment: 27 / D13
Location: Wareham ON
Team: DARC – Neil Peterson, Ken Cook, Darrell Markewitz
Furnace: Norse Short Shaft
stone slabs with clay fill
small tap arch (top extraction )
Size: 25 x 35 cm x 63 H
Source: suggested by LAM
Tuyere: 25 mm ID ceramic tube
Placement: no information on base
about flush with wall
angle start at 25 down, repositioned to 10 down
Bellows: vacuum blower
Air: 410 l/m
Charcoal: 153 l / 41 kg broken hardwood
Consumption: about 2 kg charcoal every 22 minutes
Ore: hematite grit with 2.3 kg Virginia rock (poor) as seed
12.3 kg total
Sequence: ore added as small charges .5 to 1 kg
Duration: about 4 3⁄4 hours (not including preheat)
Result: about 2 kg badly sintered high carbon (not forgeable)
Notes: proof of concept on stone slab construction
large amount (+ 3 kg) unsintered iron fragments recovered
results as expected with low volume air
Date: November 2007
Experiment: 28
Location: Wareham ON
Team: (course) Peter Martin, Shawn, Scott Pond
Furnace: Norse short shaft
clay cob set on low plinth
small tap arch (top extraction)
Size: 25cm x 72 H (+ 15 cm collar)
Source: ongoing research
Tuyere: 25 mm ID ceramic tube
Placement: 10 cm from base
about 5 cm in from wall
angle at 22.5 down
Bellows: vacuum blower
Air: 750 l/m
Charcoal: 60 kg broken hardwood
Consumption: about 2 kg charcoal every 7 minutes
Ore: Stelco taconite (seed of poor Virginia rock)
18.2 kg
Sequence: ore added about every 7 minutes
increasing from .5 to 2 kg
Duration: about 4 1⁄2 hours (not including preheat)
extra long (2 hour ) split wood preheat
Result: 5.5 kg workable bloom with slight carbon
Notes: - text book smelt for teaching
Date: March 13, 2008
Experiment: 29
Location: Smeltfest 08, Lexington VA
Team: Skip Williams, Jake Keen
Furnace: Medium Shaft
clay cobb
tap arch (bottom extraction)
bellows plate with blow hole
Size: 30 cm x 105 H
Source: based on Williams' observations at Eindhoven
Tuyere: tapered copper to 2.7 cm ID
3 cm dia. blow hole
Placement: natural set base
about 6 cm set back to tuyere tip
Bellows: electric blower
Air: not measured
Charcoal: 45 kg broken hardwood
Consumption: about 2 kg charcoal every 8 minutes
Ore: Virginia Rock
23 kg (roasted)
Sequence: ore added about every 12 minutes
charges range from .5 to 2.3 kg each
Duration: about 4 1/2 hours (not including preheat)
Result: 5.5 kg bloom - soft iron with some carbon
Notes: - bloom has pronounced crescent shape
Date: March 16, 2008
Experiment: 30
Location: Smeltfest 08, Lexington VA
Team: Jake Keen
Furnace: Medium Shaft
clay cobb
tap arch (bottom extraction)
bellows plate with blow hole
Size: 30 cm x 105 H
Source: based on Williams' observations at Eindhoven
Tuyere: tapered copper to 2.7 cm ID
3 cm dia. blow hole
Placement: natural set base
about 6 cm set back to tuyere tip
Bellows: electric blower
Air: not measured
Charcoal: 60 kg broken hardwood
Consumption: 2 kg charcoal every 13 minutes (varies)
Ore: DARC Dirt 1
30.2 kg
Sequence: ore charges range from .1 to 2.5 kg each
Duration: about 5 1/2 hours (not including preheat)
Result: 1.7 kg bloom - high carbon
Notes: - bloom has pronounced crescent shape
Date: March 17, 2008
Experiment: 31
Location: Smeltfest 08, Lexington VA
Team: Jake Keen, Skip Williams
Furnace: Medium Shaft
clay cobb
tap arch (bottom extraction)
bellows plate with blow hole
Size: 30 cm x 105 H
Source: based on Williams' observations at Eindhoven
Tuyere: tapered copper to 2.7 cm ID
4 cm dia. blow hole
Placement: natural set base
about 13.5 cm set back to tuyere tip
set at 22 down
Bellows: electric blower
Air: not measured
Charcoal: 68 kg broken hardwood
Consumption: 2 kg charcoal every 12 minutes (varies)
Ore: Virginia Rock
59.5 kg
Sequence: ore charges range from 1 to 3 kg each
Duration: about 5 1/2 hours (not including preheat)
Result: 7.2 kg bloom - soft iron
Notes: - position of the blow hole moved up over smelt
results in tall, narrow bloom
Date: April 13, 2008
Experiment: 32 / D14
Location: Wareham, ON
Team: Neil Peterson, Ken Cook
Furnace: Econo Norse
smaller size in metal barrel frame
set on plinth (bottom extraction)
Size: 20 x 70 H
Source: based on DARC design
Tuyere: 25 mm ID ceramic tube
Placement: 15 cm from base
about 5 cm in from wall
angle at 20 down
Bellows: electric blower
Air: start at about 450 – finish at 365 l / min
Charcoal: 34 kg broken hardwood
Consumption: about 2 kg charcoal every 14 - 17 minutes
Ore: DARC Dirt 1
18 kg
Sequence: ore added as 2 kg charges for most of smelt
considerable re-cycle of tap slag
Duration: about 4 1/2 hours (not including preheat)
Result: 2 kg bloom – workable iron
Notes: - full scale test of DARK Dirt 1 in standard smelter
Date: April 30, 2008
Experiment: 33
Location: Heltborg, Denmark
Team: Arne Espelund
Furnace: Norse Medium Shaft
clay cobb
bellows plate
tap arch (bottom extraction)
Size: 25 x 88 H (used)
Source: test of two stage process suggested by Espelund
Tuyere: 25 mm ID steel pipe (tapered)
Placement: 10 cm base
set just flush with bellows plate
angle at 20 down
Bellows: 'Danish standard' vacuum blower
Charcoal: 13 kg broken hardwood
Consumption: about 2 kg charcoal every 11 minutes
Ore: Guldager Bog
15 kg
Sequence: ore added as 1 kg charges
Duration: about 2 1/2 hours (not including preheat)
Result: 11.5 kg high iron content slag
Notes: - test of theoretical method proposed by Espelund,
stage one is producing volume of iron rich slag...

Date: May 2, 2008
Experiment: 34
Location: Heltborg, Denmark
Team: Arne Espelund
Furnace: Norse Medium Shaft
clay cobb
bellows plate
tap arch (bottom extraction)
Size: 25 x 88 H (used)
Source: test of two stage process suggested by Espelund
Tuyere: 25 mm ID steel pipe (tapered)
Placement: 10 cm base
set just flush with bellows plate
angle at 20 down
Bellows: 'Danish standard' vacuum blower
Charcoal: 12 kg broken hardwood
Consumption: about 2 kg charcoal every 11 minutes
Ore: Gromps from stage one
7.75 kg total
Sequence: ore added as 1 kg charges
Duration: about 2 1/2 hours (not including preheat)
Result: no iron is produced
Notes: - test of theoretical method proposed by Espelund, stage
two is re-smelting gromps to bloom
- method cosidered overly complex
- may not have been enough 'ore' material used

Date: May 4, 2008
Experiment: 35
Location: Heltborg, Denmark
Team:
Furnace: Norse Medium Shaft
clay cobb
bellows plate
tap arch (bottom extraction)
Size: 25 x 113 H
Source: based on past experience
Tuyere: 25 mm ID steel pipe (tapered)
Placement: 10 cm base
set just flush with bellows plate
angle at 23 down
Bellows: 'Danish standard' vacuum blower
Charcoal: 20 kg broken hardwood
Consumption: about 2 kg charcoal every 9 minutes
Ore: Heltborg / Swedish / Guldager bog ores
15.2 kg total
Sequence: ore added as .8 to 1.6 kg charges
Duration: about 3 1/2 hours (not including preheat)
Result: 1.8 kg, fragments in slag block
Notes: - demonstration smelt of standard method
Date: June 14, 2008
Experiment: 32 / D14
Location: Wareham, ON
Team: Ken Cook, Neil Peterson
Furnace: Banked Short Shaft
Size: 20 x 70 H
Source: Viking Age - standard build
Tuyere: 25 mm ID ceramic tube
Placement: 11 cm from base
about 3.5 cm in from wall
angle at 22.5 down
Bellows: electric blower
Air: start at about 640 – finish at 735 l / min
Charcoal: 30 kg broken hardwood
Consumption: about 2 kg charcoal every 10 minutes
Ore: DARC Dirt 1
20 kg
Sequence: ore added as 2 kg charges
Duration: about 3:20 hours (not including preheat)
Result: 1.9 kg bloom as partially consolodated - workable iron
Notes: - full scale test of DARK Dirt 1 in standard smelter
Date: September 27, 2008
Experiment: 37
Location: Troy OH
Team: Ken Cook
Furnace: Short Shaft
set on plinth (top extraction)
Size: 25 x 65 + 20 H
Source: Viking Age - standard build
Tuyere: 25 mm ID ceramic tube
Placement: 20 cm from base
about 5 cm in from wall
angle at 22.5 down
Bellows: electric blower
Air: start at about 450 – finish at 365 l / min
Charcoal: 67 kg broken hardwood
Consumption: about 2 kg charcoal every 10 minutes
Ore: Williamsburg Rock
35 kg
Sequence: ore added as 1.1 - 2.2 charges
Duration: about 6 hours (not including preheat)
Result: 9.5 kg bloom – workable iron
Notes: - demonstration smelt (Quad State 08)
Date: October 12, 2008
Experiment: 38 / D16
Location: Wareham, ON
Team: Neil Peterson, Ken Cook
Furnace: Banked Short Shaft
bellows plate with blow hole
top extraction
Size: 22 x 65 + 20 H
Source: based on Hals, Iceland
Tuyere: blow hole, later inserted - 25 mm ID ceramic tube
Placement: blow hole diameter 8 cm
tuyere pipe set to 15 down, about 6 cm back
as insert, angle at 10 down
Bellows: electric blower
Air: start at about 740 – finish at 1000 (?) l / min
Charcoal: 46 kg broken hardwood
Consumption: about 2 kg charcoal every 13 minutes
Ore: Virginia Rock (poor) mixed with Taconite (275/400)
23 kg
Sequence: ore added as 1.1 kg charges for most of smelt
Duration: about 6 1/2 hours (not including preheat)
Result: 4.9 kg bloom – workable iron
Notes: - 'work dynamic test' for proposed Hals layout
- test of bellows plate / blow hole system
Date: October 12, 2008
Experiment: 39 D/17
Location: Wareham, ON
Team: Ken Cook, Neil Peterson
Furnace: Banked Short Shaft
bellows plate with blow hole
tuyere hung from above
top extraction
Size: 24 - 26 x 65 + 20 H
Source: based on Hals, Iceland
Tuyere: blow hole, tapered tuyere
Placement: blow hole diameter 5 cm
tuyere pipe set to 25 down, about 2.5 cm back
Bellows: electric blower
Air: start at about 740 (?) l / min
Charcoal: 48 kg broken hardwood
Consumption: about 2 kg charcoal every 12 minutes
Ore: Virginia Rock (poor) mixed with Taconite (1/2)
24 kg
Sequence: ore added as .8 increased to 1.6 kg charges
Duration: about 5 hours (not including preheat)
Result: 3.25 kg bloom – workable iron
Notes: - 'work dynamic test' for proposed Hals layout
- test of bellows plate / blow hole system
- use of tapered tuyere improves air penetration
- hanging air system alows access, control of smelt

TEAM PARTICIPANTS


(1) Parks Canada / L'Anse aux Meadows
Mark Pilgrim
Assisting
Birgitta Wallace / Arne Espelund

(2) Dark Ages Re-creation Company
Core Team:
Kevin Jarbeau / Dave Cox / Neil Peterson / Ken Cook
Assisting:
Marcus Burnham / Gus Gissing / Sam Falazone / David Robertson
Mehgan Roberts / Anne Graham
Karen Peterson / Vandy Simpson
Special Guests : Dr Ron Ross / Kevin Smith

(3) Gangue aux Fer
Lee Sauder / Skip Williams
Mike McCarthy
after 2005 - Dick Sargent / Jake Keen
Assisting:
Elisabeth Sauder / Vandy Simpson
IRON SMELT LINKS

Lee Sauder
Mike McCarthy
DARC - Iron Experiments

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Introduction to Smelting Iron

June 13 & 14 - 2009

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Iron Smelting from the Viking Age

Of interest to working blacksmiths, the student of history or those attempting to re-create the Early Medieval period.

IRON SMELTING in the Viking Age - is a multi-platform CD-ROM documenting ongoing experiments re-creating both SMELTING and FORGING of the Norse metalsmiths. Contains over 600 images, working plans, experiment notes and articles.

Go Iron Smelting CD-ROM for more details.
Iron Smelting CD


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Unless indicated, All text and photographs © 2005 - 2006 Darrell Markewitz - the Wareham Forge