Inspiration to Modification

Day 62


Remember these?

F- 'Split Fire Riser'
R- 'Solar Riser LH4'
Thomas Patti - 1943

(Sorry - its a horrible image)

When I saw these glass objects by Patti at the Corning Glass Museum, I immediately thought of how the hydraulic press could alter the shape of a block of steel in a similar way.

So this is what became of the concept (Very, very, first rendition)

The left corner is the result of the very first experimenting with the press day I did with David Robertson. (David had consulted heavily with me on the construction of the press before this OAC project begain.)
The tool was originally produced for potential use with my small air hammer. I never use secondary tools that much with the air hammer, primarily because of the small die surface (as repeatedly mentioned, only 1 1/2 " wide by 4 " long). Although it is true that lack of practice is part of that problem! It has a slightly tapered shaft forged from 1 1/4 ' round stock, so the working end is roughly 1 inch diameter. The shaft length is roughly 3 inches, made of mild steel. The handle is piece of flat stock, wrapped around and MIG welded on the top surface, then ground flush.

The starting block was a piece of 1/2 thick by  roughly 2 inch square.
The resulting shape was made by setting the tool on the orange hot block, then driving it downwards. I used the full power of the press (to 3000 psi), primarily to see how far through I could push the tool.
As you can see, what happened is that the tool 'bottomed out' at about 3/16 thickness. At that point the metal below the tool had most of its heat pulled off through contact with the tool and bed of the press. The increasing pressure then simply started to bend the shaft itself.


Obviously not the way to go. Interesting potential however.


The second test , at the upper right, (done April 17) started with modifying a tool. This small (cheap) ball peen hammer had been used for a different impression test initially. Result was that the pressure collapsed the walls of the eye around the original wooden handle. First I used a drift to re-open the eye and straighten the bent head. The hammer face side was forged down to approximately the same shape and size as a standard 3/4 inch taper base candle.  Last I forged down a piece of solid 5/8 " round to fit, then drove that into the eye hot to seat it.
The starting block this time was a piece of 1 inch square, about three inches long.
First the hot block was collapsed downwards into itself. With a second heat, the tool was pressed down into the block.
One unexpected result was that the ball top end actually left an impression into the mild steel top flat plate die set in the press. Not good. 



But the finished object? Closer, but still not quite.


Both tool and object prototyping continues...

What is a 'Working Day' ?

Day 60

The last couple of days have been a bit messed up, certainly in terms of how they might track back into the grant project.

Just how do you count a working day?
Especially if you are a self supporting artist?

People who have 9 to 5 'standard' jobs just don't get it. Yes, I do not have to go someplace at a fixed time, then do something I largely do not like, mainly for someone else's bennefit.
But I also spend more time each day (even if its broken up) occupied with my 'job'. I also typically 'work' seven days a week. I don't have any holidays.

Normally I'm up at about 7 AM (often much earlier). I dress, brush my teeth, go up to my office and turn on the computer. Grab a coffee. That puts me 'at work' by about 7:10 at the latest.
Then I'm involved in business related activity until normally 10 - 10:30.  This includes all the business communications, which I in fact do first. This may be answering questions, preparing quotes and design work. Keeping my business records (including all that tax stuff for the sole bennefit of the Government). There is time spent on 'outreach' - here being researching, writing, formatting and posting for the blogs. Attempting to keep the web sites up to date.

By about 10:30 or 11 AM, my brain is about toast. Some days the desk / computer work runs straight through to noon. By then I'm *really* fried.

During the grant project, I have been seriously trying to keep 'non grant' work to a bare minimum. I'm keeping a daily diary, when I note what I've done each day. Note that I do not consider that work required as part of keeping the Wareham Forge functional as 'non grant' time. Monday I spent a hour compiling my quarterly HST, for example.  A counter point was that this morning I spent roughly a hour and a half making up a design rough for a possible project for *after* the grant runs out. That time I will not include under the project grant.

Afternoons are generally spent in the workshop itself, normally starting some point between 1:30 - 2 pm. Once again, there is a lot more to undertake in the shop than just hammer at the forge. Supply trips (Monday morning I rushed in to purchase propane, elapsed time was 1 1/2 hours). Clean up and maintenance. Equipment construction and set up.
Now take one of the work sessions documented here, say the one shown as 'A Typical Work Session'.
First I need to figure out just what I'm going to do. This may include some organization and record keeping. Typically 15 minutes.
Then, having selected the bloom to work on, I start the gas forge and start getting the required tools, etc organized. All while waiting for the gas forge to get through its pre-heat. Typically 10 minutes.
Now I can place the bloom piece into the gas forge for its initial heat soak. Then I turn my attention to the preparing the coal forge. Clean, sieve, lay and start the fire. Wait for that fire to run through its coking phase. Normally sweep the shop floor while this is happening. Typically 30 - minutes.
By now the bloom piece is pre-heated and can be transferred to the coal forge to bring it up to welding heat. This requires some attention. I dance back and forth preparing the air hammer and hydraulic press for operation.
Elapsed time from when I entered the workshop till I pull the bloom piece out to the anvil? Typically 1 1/2 to 1 3/4 hours.
Insert forging the bloom here, normally about 1 1/2 to 2 hours.

Now at that point I'm, pretty much beat. Forging multiple kilogram masses at welding heats is exhausting and demanding work (even *with* my two machines).

Add some time shutting things down. Normally its now something between 5 - 6 pm.
I make that a 'normal' work day of 7 a to 5:30 p, with 1 1/2 hours average for lunch = 9 hours.

Then there are the *long* days.
Now do that basically 7 days a week.


I was extremely pleased - and quite surprised, to get this OAC grant! (Ok?)

Taking the amount awarded in the grant and converting it into normal working days, at 5 per week and weekends off, the total came to * 43 * working days. Use that standard, with the 14 days for the Smeltfest research trip considered additional time.  With the grant effective February 15,  the last grant day would be Thursday April 26.
Tomorrow.
See the 'day count' at the top of this post?
I have deducted all the time I have spent on things that I do not consider part of this project. I've been counting 'full days' (not working hours!)
Today's total?
* 60 * days

I'm actually going to try to squeeze out additional working time past that April 26 date for the grant project. I have an academic paper to deliver at the International Congress on Medieval Studies on May 10. My intent is to extend my own work on this project to that date.

I think the Ontario Taxpayer is certainly getting their money's worth...


PS - this piece just took me one hour to prepare

Sometimes a great (?) notion...

(Day 58 continued)

For the last week in the forge I have been working to prepare materials with a specific object in mind.
Generally this is *not* how I have been proceeding with the project. As I do feel I still have a lot to learn about how best to approach compacting down each individual bloom. I still don't really feel confident that I can pick up a given bloom - then absolutely undertake the best possible method to produce a determined result at bar stage. There is no doubt that all this bloom to bar work is greatly increasing my skills, but...

I had three possible objects in the back of my head to create as part of this project. All three incorporate blown glass. Working with a 'raw' piece of bloom iron creates texture, an irregular outline and considerable strength.

Forged Bloom Bowl

I've always loved blown glass. It offers colour, transparency, and smooth fluid lines. The counterpoint to forged metals is obvious.

So this is the concept :

Rough for 'Fluid Core'

This most certainly is one of those times where my illustration ability falls so very short of being able to adequately picture the concept.
For 'Fluid Core', three pieces of forged bloom iron would be joined to create a tall tripod like shape. The surfaces would be roughly polished, as seen in the bloom bowl above. This creates surfaces that are both flat and shiny, but also darkly pock marked. The ragged edges from the original bloom are left in place as much a possible. Part of the technical challenge is compacting the parent bloom mass enough to be structurally solid, but not welding / folding so much as to blend in all the cracked edges.
The glass would be formed in place over the metal. On the lower surface, it would be allowed to slump down to form three lobes between the metal plates I'm envisioning the top of the glass as a long oval form.

These are the individual plates I have forged up to use for this object :

Bloom iron plates

All three pieces are forged down from the 'Slag Pit 2' bloom (# 49 - November 2011) The starting bloom mass was 4650 gm. It was the first piece that I worked under the new hydraulic press, first cutting it into four more manageable sections. (The fourth piece, smaller and more fragmented, was forged up into a working bar.)
You can see how I have drawn the individual segments into long thin plates. The next step will be shaping these into more of a triangular profile. I still have not decided if I will simply MIG weld the plates together, or make a separate cylindrical core to serve as the attachment piece.

I have already spoken to local glass artist Kathryn Thompson about co-producing this  piece (and possibly two others). I have been a huge fan of Kathryn's work since I first met her. (Kathryn was one of the contributing artists for 'Out of the Fiery Furnace' in 2005). Other than showing her my rough concept, I intend on letting her determine how best the glass work should be undertaken.

I will be using some of the OAC grand funding to directly commission this glass work from Kathryn. (Another positive effect of the grant!)

Building a PRODUCTION Iron Smelting Furnace

 Day 58

Making a bloom requires an iron smelting furnace. I have built dozens over the years, most on the 'Norse Short Shaft' model. The work on the actual smelting end (creation of the iron blooms) has been a combination of a learning process extended into experimental archaeology. Furnaces are often purpose built to test a specific variable, and commonly only used one or two times.

I have decided to take the opportunity offered by the OAC project grant to build a more durable 'production' version furnace.

The first day's work consisted of gathering the available supplies and possible pieces, plus cleaning up and preparing the site. The furnace built for last year's 'slag pit' experiments was examined to see if it could be simply repaired. 

Damage to top of Fall 2011 furnace

The nature of recording the slag pit experiments had meant picking up and moving the furnace itself after each smelt. The furnace had been returned to a prepared base and covered over with a plastic drum for the winter. The combination of all that shifting, and the winter weather, had resulted in a fair amount of damage. This certainly could have been repaired, but I decided to build a brand new furnace.

There would be a number major elements used for the production furnace which should combine to greatly increased durability :

use of a copper tuyere 

base area built of fire brick

metal sheathing over the shaft

use of sand / horse manure / clay mix

Part way through construction, with measurements

One of the things kicking around the shop was an old metal trash barrel, with the bottom pretty much rusted out. It was roughly 60 cm tall and about 35 cm diameter at the small end. Almost exactly the same size as the exterior of a short shaft furnace. I decided to use this as a combination form and protective shell for the upper shaft. The base area would be built from a circle of dense fire brick, both for durability and stability.

Firebrick base as laid out

 The furnace was constructed on the shelf that makes up one edge of the Wareham smelting area. This places the bottom base of the furnace up about 25 cm above the working floor. To create a hard bottom and stable surface, a (broken) concrete paving slab was placed first. The furnace is being constructed with a large tap arch - large enough to allow for possible bottom extraction of the bloom (although my normal method is a top extraction). The location of the tuyere will be to the left hand side as seen above. The placement of the fire bricks on edge creates a heavy and flat surface for the shaft of the furnace to rest on. The circle of standard construction bricks defines the boarder between the furnace and the natural earth surface.

Brick layer with clay fill 

The first layer of clay was a mix of 50 / 50 rough sand and standard ball clay (mixes by volume). This was used as a mortar to fill the wedge shaped gaps between individual bricks. Next the space between the firebrick circle and the outer retaining bricks was filled. Finally a sloped shoulder was created from clay to the top of the fire brick layer. A full bag of clay was required here.

Next, the bottom of the metal barrel was cut out. A slot was cut on one side, roughly 7.5 x 7.5 cm. This would be the hole allowing for the insertion of the tuyere later. The measurement from the top of this hole to the top of the barrel was 40 cm. (When positioned, the angle of the tuyere will place its tip even lower, so there should be a good 50 cm of stack height.)

Dry measures for the clay mixture

The furnace walls were composed of a mixture of course sand, shredded dry horse manure and clay. The clay used was 'New Foundry' - a higher firing temperature clay (which I had gotten from Lee Sauder). The ratio is roughly 25 / 25 / 50. This is mixed dry by hand before the water is added. (I took considerable care to make sure the mixture was fairly stiff, particularly with the first layer.) The material was kneaded up to an even consistancey, then hand wedged into balls and left to stand for about an hour before applying. (Note that Lee recommends letting the clay stand overnight to even out the moisture content. Yes - I did rush this a bit!)

First wall layer applied (tap arch at bottom right)

The individual balls were broken in half, with the individual pieces blended in carefully as the walls were built up. The metal form allowed to exert good pressure, but still keeps the overall shape consistent (and under control!) The thickness of the walls was kept to roughly 6 cm at the bottom, thinning slightly to closer to 5 cm at the top. You can see how the interior diameter is matched to the ring of fire bricks.
Because the metal barrel tapers, the interior diameter of the furnace will taper slightly as well. This is actually ideal, as it moves the tuyere tip slightly off the direct line of ore falling inside the furnace. (We have seen this arrangement reduces the amount of slag that collects on the tuyere tip.)

I finished up a long working day just as the sun was getting close to the horizon and the black flies were starting to come out. Expect some images of the final construction, once the clay has had a couple of days to stiffen up and I mount the tuyere.

Demonstrating the Aristotle Furnace

Day 54



This video clip was shot by one of the participants at my March 10 demonstration at the monthly meeting of the Ontario Artist Blacksmith's Association (OABA, through the work of editor Sean Stoughton, regularly posts video on to its own YouTube site. )
The sound quality is uneven, and as hand held footage is a bit jumpy. The beginning explaination is missing, but if you stick with the clip, you will mostly get the sense of how the small re-melting furnace works.

For more info, download a handout at: http://www.warehamforge.ca/ironsmelting/Aristotle-HO.pdf

An earlier description of this demonstration was made here on B2B : March 11 - the Aristotle Furnace


Saturday and Sunday this weekend were spent taking part in a presentation by the Dark Ages Re-Creation Company at the Royal Ontario Museum. The ongoing experimental iron smelting work was part of the presentation. Although strictly not part of the B2B project, reference to the OAC was made (via a sign).

Forging a Copper Tuyere

Day 54

This is a note of the work undertaken on Wednesday April 11 (Day 52).

Lee Sauder had this to say about his use of a copper tuyere:

1) The original inspiration to try the copper came from the Catalan furnace descriptions. I tried it the first time I tried the flue tile, after the first Early Iron at Cooperstown, so I guess that would have been late ‘04 or early ‘05. I have used them almost exclusively since, with the Coated Tyle furnaces, the Cadhinos, the big steel and refractory Aphrodite, and all the clay furnaces.

2) I have found that they will melt if they are much less than 14 inches long (this is with about 2.5 inches protruding into the furnace).

3) I looked back through my notes, I think I used the last tuyere for 45 smelts before I retired it, but I’m not sure. It didn’t fail, it was gradually thinning, and I didn’t trust it anymore.

I had made a first attempt to try out a copper tuyere for my own smelts # 7, #8, # 12 in 2005. My problem was at the time I did not have suitable copper material to work with. I had tried cutting and forming from 1/8 inch thick copper sheet. That thickness just was not enough to either withstand the furnace temperatures or transmit heat off fast enough to prevent erosion of the tip. Work with copper tuyeres was abandoned in favour of using a standardized ceramic tube (starting in 2006).

Last year at Quad State, I had picked up a large bar of copper, 2 x 1 1/2 x 12 inches. (Luckily, I paid less than current scrap prices = $20.) I had actually intended this material for an artistic forging project, but like many good intentions, the piece got tucked away and pretty much forgotten.

With the reminder caused by the slag rings recovered at Smeltfest this year, and wanting a break from the heavy forge work this week, I pulled that block out. The starting weight was 4358 gm.
The first step was to combine draw, widen and flatten the material to a rough flat bar. This was done under the air hammer - mainly 'pushing' the material under the dies. (Starting at the far end, and pushing the material back towards the tong end as the dies collapsed it.)
Copper is wonderful material forge! It is extremely soft at a dull red colour, and even when the temperature drops, it remains soft and workable. This softness also means less vibration shock back into your hands. The big problem is heating a large piece. Heating in the propane gas forge, I was never able to get it much more than a 'bright red'. The end of the material hanging out of the forge was radiating off heat almost as fast as the burners were applying it.

After the initial flattening
(sorry for poor image quality)

At the end of the first stage, I had a flat bar roughly 1/2 inch thick, 3 inches wide, and about 20 inches long. You can see most of the thickness had been transferred to length, working on the flat die on the air hammer. In the image you can see how I cut off the last 4 1/2 inches (955 gm) of material.

The remaining piece was forged to a taper, both in thickness and width, over its length. This was done in a number of steps. Initially the material was worked by placing it to 90 degrees to the long axis of the dies. Next the surface was worked under a Hoffi style crowning top die. This was followed by a fair amount of working the surface with the cross peen. Again the direction of the peening was done at 90 degrees to the long axis of the material. The net effect here (for the non blacksmiths) is to primarily force the material side to side - not end for end. Last, the surface was worked with the forging hammer to smooth out all the irregularities caused by using the peen on such soft material. At this point the edges were also hammered to create a more or less even and straight lines.

This all created a shape like a triangle with the tip cut off. To finish the work, the peen was again used, but now over a half cylinder shaped anvil tool. Also it proved just as easy to work into the hollow created by the step from horn to face on the right hand edge of the anvil. This series of more gentle strokes gradually formed the flat surface into a half curve. This was carefully rolled up to where the two edges met - creating a conical form.
This was then worked to ensure the shape was symmetrical, and straight.

Finished copper tuyere

The resulting tuyere is 45 cm long. Its finished weight is 3394 gm.

Furnace End
2.5 cm internal diameter
wall thickness 6 mm

Air Input End
5 cm total diameter (accepts standard 1 1/2 inch threaded pipe)
wall thickness 3 mm

Credit where Credit is Due!

Day 53

Setting the Record Straight!

Part of the project grant was specifically to cover my participation in Smeltfest 2012, hosted by Lee Sauder at his Germinal Ironworks outside Lexington Virginia.
Lee, assisted by his close friend and smelting partner Skip Williams, started investing historic bloomery iron smelting methods in the 1990's. They were initially inspired by African models, then worked backwards to establish a functional and predictable technique.

Sauder & Williams, pulling a bloom from their 'African Queen' furnace.
Frontier Culture Museum, Stauton VA - 2002

I had the good fortune to meet Lee and Skip in Fall of 2002. I had only undertaken two smelts at that point, both unsuccessful. They were extremely generous with their knowledge and folding my small group (other members of DARC) into their demonstration. Although we did little more than help with some of the 'dirty jobs' I certainly learned an immense amount. They had already determined the critical high volume air flow required to correctly produce dense iron blooms. By the point I met them, they had published their research both formally and inside blacksmithing circles.

Thanks to the wonders of the internet, the Spring 2004 smelt at Wareham had a special guest, Michael McCarthy from Cooperstown NY. Mike had been smelting at the Farmer's Museum, basing his furnaces on Colonial American models. He was actually on his way back home from spending a week building and operating a Japanese tatara furnace. Although yet again tour smelt was a complete failure, a solid friendship was struck up.

Mike would organize the first Early Iron symposium at the Farmer's Museum in Fall of 2004. This gathered together Lee & Skip, Mike and myself as demonstrators, each building and operating a furnace from our various traditions. My (quite unplanned) contribution was a Norse style short shaft.

the "Gangue of Fer"
(L-R) Sauder, Williams, McCarthy, myself (back)
Early Iron 1 - Cooperstown NY, 2004

Late Winter of 2005 would mark the first of the invitational Smeltfest events hosted by Lee. Initially this was just the small group of us, concentrating on some specific aspect of furnace construction or smelting method.
Over the years a number of functional problems have been proposed and tested. These methods have then been incorporated in the continuing work of all three teams. A growing group of other enthusiasts have been included and have contributed. The core these days includes Jesus Hernandez, Shelton Browder and Steve Mankowski. Smeltfest has been fortunate to have include a number of wide flung guests on a more irregular basis, including some that have travelled a fair distance to participate. (Recent years have included Jake Keen, Tim Young and Therese Kearns from England, Jeff Pringle from California.)

In truth, the Early Iron group acts much like a think tank - with a solid practical workshop aspect. Evenings are spent in brainstorming ideas, with the raw energy of being gathered from isolation into a group of fellow enthusiasts. Days are spent testing out suggested concepts. The combination of experiences, interests and personal skills provides a unique and often intense, learning experience for us all.

My single largest contribution to the overall endeavor has been with documenting and publishing the discoveries. Almost always I am *not* the originator of these ideas. In practical work, I am typically just a 'worker bee' rather than a team leader.
I do make every attempt to make sure credit is given where credit is due.

(This clarification arose from some secondary mentions of yesterday's blog post. Tomorrow I will expand on those additional comments.)