Friday, June 15, 2018

Using up the Leftovers..

.. or Making Do in the 'Carefree Life' of the Independent Artisan

As regular readers know, and visitors to my web site can see - I run courses out of the Wareham Forge.
A lot of courses. (*)

I run just the 'Introduction to Blacksmithing' weekend course at least a dozen times any given year.
Every time, the first basic project is a simple S hook. I make one as a demonstration.
about life size - 1/4 inch square stock
I no longer sell small objects like these (in fact don't really undertake any direct retail shows any more).
So I end up with a 'few' left over.
A lot left over.

I was contacted at the beginning of June by the people who operate the 'Escape Quest' franchise in St John's Newfoundland. They had been in negotiations with Parks Canada about opening one of their 'Adventures' at L'Anse aux Meadows NHSC. Their rough concept was to use the 'slave quarters' building at LAM for the activity.
'Slave Quarters / Storage Hut' is building to right (1996)
The interior of this sod wall construction building is roughly 2 x 3 metres. (Although it looks larger in the image above, remember that the walls are at least 1 metre thick!)

They wanted a lot of stuff.
Ideally delivered by the end of the month.

One of the things on their list was S hooks.
Thirty S hooks.
(Did I mention I end up with a lot of S hooks?)
I had a few left over.

Another thing on their list? Hand forged chain.
Request was for 10 feet, later increased to 15 feet.

Given this was 'Escape Room' - from the 'Slave Quarters', what came to mind was this:
Complete artifact chain
This object, from the Viking Age, is from Ireland. Now in the collection of the National Museum in Dublin. I had seen this in 2014 during two days spent there.
The construction is individual large circles made of square iron bar, forge welded closed, then pinched flat into a collapsed 8 shape. (This is one way to yield the most chain length out of the least amount of metal used.)
I have seen some other Norse era chains using simple 'closed S' shaped links.

Now making chain from starting straight bar is both time consuming and often tedious work. Time was most certainly at premium on this project (**).
I did mention I have a lot of S hooks left over?
This is what I came up with:
'Escape Chain' - detail with starting S hook
'Escape Chain' - complete length

I used another 24 on hand S hooks.(***)
Each had the one pointed end re-shaped to curl the tip into a small loop. Then both ends were collapsed inwards into a closed loop. These were then linked together in a four element set, each making about two feet.
I forged a series of large diameter rings out of 3/16 x 1 inch flat stock - to about 3 inch diameter. These then were used to attach each of the looped chain segments. An extra large ring was placed on either end.
The finished length was just over 13 feet total.

This use of the previously made S hooks massively reduced the 'just now' time involved to produce the finished chain.

From an artifact prototype standpoint, certainly the object created can only be considered loosely based on the original Norse chains. The individual link elements have reverse twisted central sections. This a bit of extra complexity in the forge work I would consider quite unlikely in a basic functional object like a slave chain.

(Did I mention the sea chest hinges for the same order? Total 30 individual hinges have been made.
There are 15 matching hasps to still make. And six Norse padlocks. And a cooking pot. I don't have another available forge work day open until June 25 at this point.)

(*) For those interested in the 'Business of the Artisan' :
For the last three years, about 90% of my income has been from teaching. This includes my twice yearly segments at the Haliburton College Artisan Blacksmith program, but most importantly from weekend training programs here at Wareham. 
(Another big chunk has been from educational and research programs. That 'income' is normally completely erased by the raw travel and related costs. Despite the large amounts involved, almost always I end up paying out more than came in.)

(**) I had my first contact with Escape Room Newfounland on May 30. Between determining exact requirements and producing a hard quote, the final confirmation of the order was not given until June 5.
June is already an extremely tight month for me. I had a major historic demo to mount on the other end of Ontario, one weekend course, two iron smelting events, a sculpture to mount for exhibition. From June 5 I counted only SEVEN available days not already committed to other projects. (Oh - that was eliminating entirely any possible 'day off' for that entire month!)

(**) And I still have at least six more...

Wednesday, June 13, 2018

Steel Stocks (+ Tariffs?)

At the time of this commentary, Canada has decided to stand up to the USA imposed tariffs of 25% on imported steels into the USA, applied on June 1. Announced were import duties to be applied to American made steel coming into Canada, to come into effect July 1.
Both tariffs apply to the full range of iron alloys, from mild steel, alloy steels and cast iron, both as raw industrial bars and worked objects.

How will this effect the small scale Artisan Blacksmith?

Not much

First : What is the source of our raw bar material?

image from Kreuger Steel
In most cases, this can be difficult (if not outright impossible) to tell.
Industrial sourced mild steel comes typically as 20 foot lengths (1) . Where you might be in the 'supply chain' really (dramatically) impacts the 'cost per foot'.
As a full time professional shop, I normally purchase in anything from 2 or 3 full lengths, up to 200 - 400 worth of individual stocks (shapes and sizes). In the case of the Wareham Forge, this includes the usual square, round and flat mild steel bars, as well as pipe, tube (square), angle and channel structural steels.
For all this I use an 'intermediate' level supplier (2)

At the amounts any of us purchase, typically the creation source of the material is unknown. 
• One clear exception to this are the various structural shapes I get - which are clearly marked (made in) 'Canada'. I have to report that the quality of these materials is uniformly excellent.
• The other exception is 1/4 inch square bar. This material has been coming in from 'offshore' / not North American sources for about the last 20 + years. (see more on this below).

3/8 square - 1/4 square - 1/8 x 3/4 flat
Second : Are we really getting what we want?

The ideal material for most Artistic Blacksmithing work, reguardless of shape or size, would be hot rolled mild steel bar. (as seen on far left, above)
• The metal has a somewhat protective, dark grey 'fire scale' surface :
   - This slows the development of low temperature oxide / red rust.
   - This is roughly the same surface that is created when forging.
• Although the bar has slighly rounded corners and does not have precise measurements, it will be hammer forged anyway.
This is the cheapest way to produce the metal stock.

Increasingly however, many of the smaller stock sizes are not available as either North American produced - or as hot rolled materials:

SMALL FLATS - Almost all 1/8 thick materials, and increasingly some 3/16 thick, now come as 'sheared'. Here what is basically a giant cutter is used to sever off narrow strips from large plates of steel.
• The metal does NOT have protective (or uniform!) fire scale coatings. It rusts quickly in the shop environment. Parts of the bar not being forged now must be heated and hammer worked to create uniform appearance.
• The shearing process actually deforms the metal into a slightly cupped cross section.
• If the cutter blades are worn, there can be sharp edges to the lower edges. Sometimes sharp enough to act like knife blades (!)
(You can see both effects on the edges of the bar on right side of the image above.)
• Depending on source, sometimes the bars are twisted and distorted.

1/4 SQUARE - Starting in about 1995, this basic small stock was being supplied from various (unknown) 'off shore' sources. The material now comes as 'semi cold rolled. (seen at centre, above)
• The price drastically increased - about 4 - 6 times more expensive (see discussion below)
• The metal is supplied too hard - it literally shatters when attempting to cut. The required annealling step has been skipped (likely replaced by water cooling). This causes razor sharp edges on cutting - that need to be ground clean.
• The material is often of substandard quality, randomly. (Supplied in 12 foot bars, I have seen a crack running down an entire length.)
• The material is finished without the protective fire scale surface.
• To protect during ocean shipping, unknown, and sometimes toxic coatings will be applied to the bar surfaces.

SMALL ROUNDS - Occasionally, material is produced by 'extrusion', rather than 'rolling' (imagine squirting out tooth paste!).  I have seen this for both 1/4 and 3/8 sizes.
• 1/4 round is almost always 'semi cold rolled', at least in terms of lacking the fire scale coating. The metal still comes correctly annealed. This does increase rust formation and causes extra work to create a uniform surface colour and texture.
• 3/8 round is sometimes found to have surface flaw 'gouges', which can run down the entire length of the stock bar. (Not a common failure, this caused by debris caught in the extrusion die.)

Third : Pricing and possible increases?

Right now the price for new steel bars is roughly somewhere between $0.65 and $0.75 per pound.
Of course, typically at our purchase amounts, price per foot is of more interest.

I took delivery of several of my commonly used sizes / profiles on May 30 (ordered about May 20).
1/4 square = $0.75 per foot (ordered 200 feet) (3)
3/8 square = $0.60 per foot (ordered 200 feet)
1/8 x 3/4 flat = $0.54 per foot (ordered 60 feet)

Now I strongly suspect that the 1/4 is produced outside North America (so will not be effected by the increased tariffs).
I strongly suspect that at least the 3/8 is produced in Canada (so again will not be effected).

So - for sake of the commentary, run the increased tariff possibilities:
1/4 square = $0.94 per foot / + $0.19
3/8 square = $0.75 per foot / + $0.15
1/8 x 3/4 flat = $0.68 per foot / + $0.14

Now - use some very basic 'beginner blacksmith' type objects made with those same stocks, each uses about 2 feet of material:

1/4 square : Loom Light Candle Holder @ $15 / + $0.38
3/8 square : Fire Place Poker @ $20 /  + $0.30
1/8 x 3/4 flat : Towel Rail @ $20 / + $0.28

The key here - and a warning to Consumers :

For Artisan Blacksmith work, the primary cost component is SKILL and TIME.

Not materials.

(1) Imperial Units - used throughout.
Imperial is still the primary system used in measuring steel dimensions. 
Some Metric dimensional stock is starting to be available.
SUGGESTION : Use all Imperial OR all Metric / NOT some of both!
Metric uses different 'size breaks' between stocks. (You will find 12 mm or 14 mm, but not the 12.5 mm - which would be actual 1/ 2 inch in Imperial, for example.)

(2) - Actually Krueger Steel in Owen Sound.
I pay a little bit more here, instead of moving up one level up in the supply chain:
• I get exceptional service from the gang at Kueger.
• I am rarely in a hurry ('some time next week?'), So I get *free* delivery, when they make their normal weekly run down to Toronto.
• They are always willing to take my 'old time' measurements (imperial gauge sizes!) and convert to modern units.
• I have at this point an almost 30 year customer / supplier relationship with them!

(3) You may notice something there.
The 1/4 square is in effect over double the 'price per pound' as the 3/8 (with twice the actual volume per foot).

Monday, June 04, 2018


Original hammer / mounted in coal forge room
I have just taken delivery of a brand new build 'push / pull' style air hammer. Built by my long time friend David Robertson.

The concept behind these tools was introduced by ABANA's Ron Kinyon
An air cylinder with pressure on both top and bottom is controlled by a valving system. When air is released (via a foot switch) from the lower side, the block is dropped. At bottom of travel, air pressure is reversed, lifting the block. At the top of travel, the flow reverses again. If the bottom release is still open, the block drops again. This method cycles the head block up and down. Although the air cylinder does apply some downwards force, it is primarily the inertia of the head block that creates the impact effect between the dies. This style requires a stand alone (separate) large sized air compressor (needs 10 CFM at 90 psi).

David also built my original air hammer, a much earlier (and simpler) build based on the same principles. I had participated by funding the materials for TWO of the original pattern. David built the first prototype for himself. What he learned (with a few modifications I suggested) was used in the build of the second for my shop. This original hammer had :
• 50 lb head weight
• 1 1/2 x 4 inch die surfaces (set at 90 degrees)
• 3/4 inch cylinder shaft diameter
• 'rating' for up to 1 1/2 x 1 1/2 square stock (1)
• control via movable 'gas peddle'
• total weight of about 450 lbs
(a full description can be found on an earlier blog posting)
Now David has been tinkering, building (and selling) ever improved versions of that original light weight design for easily two decades now.  Safe to say the 'Mark 2018' is considerably improved !

New hammer / mounted on open shop floor
The new build specifications :
• 75 lb head weight
• 2 x 3 1/2 inch die surfaces (set at 45 degrees)
• 1 inch cylinder shaft diameter
• 'rating' for up to 2 x 2 square stock (2)
• control via fixed (front) lever
• total weight of about 1200 lbs (this build actually closer to 1400 lbs)

What is clear right from the specifications is that this is a much more robust machine. Frame weight alone is three times the old machine. The head weight is half again as much (with the corresponding increase in available force).

Some of the details (3) :

Close view of standard dies

One big functional improvement is the attachment of the dies at a 45 degree angle. 
This allows for long pieces of bar to be worked - able to extend the bar past the edge of the machine for both the spread and draw action. On the older machine, the dies were set at 90 degrees to the frame, which limited the spread action to only the last 12 inches of a bar. I have had David align the dies so the draw action will allow a bar to extend through the open door to the coal forge room. This effectively would allow me to extend the working end of a bar about 5 feet past the dies in that direction.
This alignment / attachment does result in the basic die blocks being a bit shorter ( reduction in length of 1/2 inch), but this is certainly balanced by the increase in width (plus 1/2 inch). I had always found attempting to use any accessory tools for punching difficult on the original hammer. A combination of the size (only 1 1/2 wide) and the action (you had to quickly insert the punch as the head moved on the upwards stroke).

Second of the other huge improvements to the new design is the construction of the lower die pillar - also clear in the image above. The original build used a pair of 2 x 2 heavy wall (1/4 inch) square tubes as the support for the lower die block plate. (I had filled those with lead shot to help increase machine weight and thus stability). You can clearly see the construction of the lower die pillar is a set of 1 x 6 inch *solid* flat bars, welded into a solid unit. This massive construction vastly improves stability / rigidity of the lower die pillar. The huge increase in overall weight is primarily here as well - which improves the overall stability of the machine.

Because of the overall construction and layout of the die mounting bolts, I am expecting to be able to construct an 'extension surface' that I can apply to both the top and bottom dies. This should allow me to increase the working surface to about 4 x 4 inches. The utility here would be for ease of texture punching and hopefully compaction of bloomery iron. (4)

Front - block guide
The third huge design improvement is the way the head block is supported.
On the original build, two flat plates extended off the sides of the head block. These plates ran down a channel formed by built up bars bolted together. The bearing surfaces were flush mounted brass plates. As these guides were open at both the top and down each hammer block side - there was a potential problem with fine particles accumulating along the moving surfaces. To avoid excessive wear and more importantly easy motion, considerable lubrication needed to be applied. This in turn certainly created a lot of oil mess - but increased accumulation itself.
The new build uses a 'block in a box' system, lined with replaceable nylon bearing surfaces. Although daily application of a light lube (like WD40) is indicated, this new construction is certainly both more stable and likely to prove more durable.

Upper right - showing adjustment levers
Fourth major improvement is the addition of a number adjustments to the working action.
On the older machine, there was not much you could adjust other than the relative striking height of the top block. (see also # 5 below)
There are three additional adjustments possible on the 2018 build, each easy and quick via levers:
a) Blue = Impact Force adjustment.
This allows you to quickly set for a maximum delivered force to each stroke. Although impact force can certainly be controlled by the speed (inertia) of the individual stroke on the foot control. This additional method of limiting input air (so maximum potential force) is likely to prove handy when working softer materials (copper based) or for detailed work (smaller stock sizes, decorative punching / stamping).
b) Red = Head Speed adjustment
This chokes off the total amount of air supplied into the hammer. The net effect is to slow down the cycle time between individual strokes. Although this does reduce inertia / impact force, this is not the prime intent. With the block moving slower, this allows for more setting time between individual strokes when using punches and stamps.
c) Yellow = Lock Up
This will make the hammer head lock upwards in the full open position. Essential for replacing modified dies or accessory tools. On the old build, you had to (attempt to) snap a suitable length bar into the die gap - as the hammer was cycling ! (5)

Lower 'air trip' valve
The fifth improvement is a better attachment for easy adjustment to the air trip valves. This improvement is a small one - but does correct something that was a major headache on the original. There is a lever type trip valve on either side of the head block. These control the switching of the high pressure air from top (drop) to bottom (lift) into the main cylinder. The air trip valves can be adjusted to set just where in the total up and down motion of the block the direction of travel is changed. The top setting is rarely modified (at least in my experience). The lower valve setting does control just where the hammer head will strike. This would normally be adjusted to conform for the 'resting' height of various accessory tools that might be in use.
The old hammer had a pair of small bars running down each side of the head block guides. The air trip valves were held in place by a pair of small bolts & nuts. As there is some sideways force (and a lot of vibration) resulting from every stroke, these often drifted out of alignment. (As well as up and down changes, shifting too far sideways kept the valve from operating correctly.)
You can see the new system uses the switch firmly bolted (4 x) to a heavy flat bar - which sets into a box attachment, keeping the valve from shifting out of alignment. A good sized 'wing nut' styled bar now is used to alter the position of the bottom height control.

Base, showing activation bar
The sixth improvement is the overall construction of the (exhaust) control lever. For this style of machine, bleeding air from the lower side of the cylinder activates the motion. The more air gets bled out, the faster the head motion cycles / the harder the impact stroke (and increase in strokes per minute as well).
On the original machine, the activation was via a separate 'gas peddle' styled control. I had it set up on a long hose - which sometimes proved valuable if I was working one end of a particularly long bar. (A feature that honestly was rarely necessary.) In the end the stability of the small foot peddle overpowered this possibility.
The new build uses a durable construction for a long bar extending along the whole front of the machine. The air exhaust is through the ball valve seen to the top right of the image. (6)

In this image you can also see the mounting for the hammer. It came supplied with a heavy rubber mat to cushion the base and reduce both vibration and possible floor damage. (Most shops have poured concrete floors.)
You can see that I have set the air hammer on to a raft made of four lengths of rail road tie - total is 36 wide by 48 inches long. These in turn rest on a dug out base of about 8 inches of sand pebble mix. I do expect some settling of the entire mount as the machine is used.

Overall First Assessment ? : 

A great improvement in construction detail, potential durability, ease of adjustment. 

As installed - image by David Robertson

(1) - I have seen up to 1 1/2 x 4 billets drawn out on that first air hammer. Slow - but it did manage it! 

(2) - This easily represents 'as big as I want to move around' !

(3) - At time of this writing, I freely admit that I have not actually * used * this new hammer yet for any forge work. (Expect a further commentary to come !)

(4) - I have built / altered a 30 ton hydraulic press specifically added for this task already.

(5) - Obviously a passive blocking bar should still be inserted between the dies before getting your hands any place near the die blocks!

(6) - I did find this a bit noisy in our settting up tests. Attaching a couple of feet of simple hose to the downstream side will allow the rushing air to vent further away. 

* With thanks to David Robertson for proofing and fact checking *

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

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