Friday, March 16, 2018

Seeking the 'Three Wise Men'...

Knowledge / Skill / Experience

This commentary is framed up against a number of similar first contact requests and questions I've had over the last month (especially).
"My 12 year old (son) has been watching 'Forged in Fire' and is keen to learn blacksmithing. Is there a one day course you teach?"
Or some variation on this theme.

No. No. No.

Right off:
Go and read 'Teens as Students'
then come back to the rest of this...

Knowledge can be had through study.

'Extensive research' is often suggested - this most commonly stated as 'hours spent on YouTube'. You watch 'Forged in Fire'? See my commentaries on that mess.
Problem there is complete lack of 'peer review' and commonly no attempt at all at to indicate the background of the presenter. Everyone is an 'expert', even if they don't actually have a clue! Status is indicated by 'click views' - not by actual achievement level.
(I went to YouTube, and did a general search using 'blacksmith knife' *)

See the title? FORGE a knife.
• The illustration of the forging process is only the first 5 minutes of a 25 minute video.
• The forging process illustrated are not so much wrong - as poorly carried out.
• The hammer technique used is horrible. Too heavy a hammer, grip choked up as a result. Thumb on top of the handle (will lead to tendon damage).
• The heat treating is effectively minimal, certainly not 'best practice'.

Ok, the presenter is attempting to simplify, de-mystify, encourage...
But :
• Briquettes are not the same as charcoal.
• Scrap wood will not produce effective forging temperatures
• Sure, you could use a small piece of scrap plate. Or a rock.
The core purpose of an anvil is *flat* and *stable*. None of the alternatives suggested are effective (even if that small plate had been bolted down to a wood stump - it would have been massively more effective!)
• A woodworking claw hammer? Seriously??
Sure, you *could*. (In Africa, I've seen video of using a fist sized rock as a hammer!)
There is a *reason* metalworking hammers are a different shape. ** 
• "I've only been forging for about 6 months"
Draw your own conclusion...

My overall recommendation:
• Do not start inside YouTube.
• Go to accomplished blacksmith's personal web sites.
See what kind of work they are able to create. How long they have been involved.
Find those with practical experience, proven ability : then look for those who may include tutorials.
• See recommendations on effective reference books for the novice blacksmith

Skill and Experience are somewhat linked.
But they are not exactly the same thing.

Skill is developed though simple repetition.
You have to do the thing, to become any good at the thing. Make 100 long points - and you will become effective at making long points.
Now just how fast a given individual will become effective at a physical task can vary a lot between individuals. Consider how long it took you to learn to ride a bike, or accurately throw a ball.

Experience is a wee bit different.
This is the 'well, that worked a lot better' factor. I can tell students that digging in the front of the hammer while making points will speed the process. How much to increase speed, but also not so much that you create creases you have trouble removing? Just exactly which hammer style and weight works best for you - for which forming step? An individual has to just get the feel for all this for themselves.

I normally suggest the most effective way for a new smith to progress is :
• take a basic course - by a well experienced instructor ***
(so you have some clue to what this is about and how to start)
• get simple working tools set up at home
• take another weekend course
• practice
• repeat, repeat

* Lest you think I am attempting to pick on specific individuals, these are the very first selections presented on the defined search.

** In the Royal Ontario Museum (Toronto) is an early Egyptian hammer for metalworking gold or copper. It is a square face with a cross peen, about the same size as the hammers I have in my shop. Date is roughly 3000 BC (predates human iron by at least 1000 years!)

*** Inside Ontario, there are three individuals who each have been teaching since the mid 1980's - and who continue to offer a range of weekend courses:
Obviously myself (!) at the Wareham Forge
David Robertson (
Robb Martin (
Both the others are also excellent teachers, and will approaches their programs (and content) a bit differently. Also a differnent range of scheduled dates that will give more options.

Tuesday, March 13, 2018



I am upgrading my own air hammer to a heavier weight, both built by David Robertson of Hammer & Tongs Studio. (go here for description)

To that end, I (HAVE SOLD) my current air hammer (Imperial measurements) :

50 lb head weight
• built on ABANA 'lift / drop' system (by R. Kinyon)
• requires separate (larger) compressor

This video shows me working on railing elements using this air hammer

This hammer is 'rated' for working up 1 1/2 x 1 1/2 inch stock.
I have worked material as large as 1 1/2 x 4 (admittedly - slowly!)

click for larger views for all images

Side view
3/4 view
front view
• Base plate = 30 deep x 22 wide• Total frame height = 88
• Total weight (approximate) 450 lbs

Closer view of working area - plastic safety shield down
- working height = 33 1/2 (floor to top of lower die)
- throat clearance = 12  (back edge of die to frame gap)
- die size = 3 1/2 x 1 1/2
- total stroke height = 9 inches
(note effective working gap between the dies is really about 4 inches)

close up of the die set up
The dies are currently set up with the bottom die having the rear half with rounded edges (to act more effectively for drawing out) See the close up image.

- head block = 4 x 4 x 10 inches
- cylinder type = heavy duty hydraulic (replaced the original lighter duty air type)
- cylinder shaft diameter = 1
- cylinder interior diameter = 2
- supply hose length = 5 feet (as existing - from compressor)
- foot peddle type control, on roughly 4 foot hose (to allow for standing back when working longer bars)


- input air control (water trap, gauge, oiler)
- full air lines (compressor to hammer)

additional die blocks made to fit this machine:
- 'Hoffi' style bottom 1/2 crown die (for spreading, seen used above)
- centre mount 'hardie hole' die block for one inch (would allow use of existing anvil hardie tools)
- centre shaft bottom die to front hardie hole (fits above)
- bolt in place front hardie hole attachment

This machine is basically 'plug and play' - fully working and ready to go.

- Requires a larger (40 gallon / 2 HP) air compressor for input air
- Air flow required is 10 cu/ft/min @ 90 PSI

It may be possible to take some of the pieces apart. Originally the bottom die block section bolted into place. This has been re-enforced with some welding - which likely could be separated with an angle grinder / zip disk. This support is made of two pieces of square tube, which I had filled with lead shot to improve the stability of the machine.

I have the machine mounted on a raft made of 4 lengths of rail tie, each four foot long. This sitting on top of four inches of sand. (All dug in to ground level).


(posting retained for history!)

Monday, March 12, 2018

Don't Call US...

... or how NOT to court a voter.

Readers may remember a couple of recent posts related to Carbon Loading, Policy, and Canadian Political Parties.

After that brush off from the Ontario Trillium Party (which instigated this whole thing) : I thought I would contact the other Political Parties.
Face it, there are elections looming first here in Ontario, and not so far off for Canada.

So this is the letter I drafted:

An open letter to Political Parties

There are elections on the horizon for Canada, and within Ontario. As members of the electorate, each of us will be attempting to draw some balance between the various issues brought forward, and policies intended, by the various Parties in contention. Each of us will have different items of greater or lesser personal concern, and in the end (hopefully) make the best choice possible between the alternatives presented.

I write to ask for specific clarification within a fairly narrow topic area:
Environment - specifically Carbon Tax.

I personally have held the value of ‘The Land’ as massively important for my entire life. I was involved, at least in a small way, in the Environmental Movement of the early 1970s. We most certainly where quite aware of the increasing human impact on our surroundings even back then. I most certainly know of my own life experience that at least the Weather patterns are shifting, locally, regionally and world wide. That the Climate is Changing is certainly a proven scientific fact. Just why this is happening may be open to interpretation. That human activity has had a measured impact, regardless of other factors, is also proven by both short term and long term records - demonstrable facts.
The truth that many of us were aware of this possibility, of the effect of human actions, for such long time, creates an ethical responsibility in my opinion. I will not reasonably live long enough to experience the worst of the Climate shift now clearly underway. That trauma will be born by the current generation of young adults. They will be faced with how to deal with the mess created, in large part, by the excesses of my earlier generation.

To that end, I see that efforts all of us, including Canadians, make now are clearly our responsibility to future generations. Now it has become the time to clean up after the indulgent party that is ended. Smaller inconveniences now may reduce massive efforts certain to be needed so very soon.

To my situation - and Carbon
(sorry this appears a bit long winded - but I’m trying to explain via figures)
I have supported myself as an Artisan Blacksmith, inside a small business operation, since 1992. I require the burning of fossil fuels to heat the forges necessary for this work. There still is no effective replacement for the use of some solid fuel. Please accept the science that weight of carbon X produces Y amount of thermal energy. A fixed amount of energy is required to undergo forging operations. Obviously this all is created by oxidizing (burning) the carbon fuel. (There are wiggle factors based on the operation of specific forge types, but this is the basic equation.)
I have made some attempts in the past to calculate exactly how much fossil fuels to carbon release I am personally responsible for in my normal operations. The calculations are arcane, with different fuels using different measurements, also switching between Imperial and Metric, Industrial and Scientific units. I am completely unable to account for the ‘raw source to workshop’ production or transport elements.


In my workshop, using the equipment available, I can generate the required temperatures by consuming the following (CDN $):

Propane = 9 kg @ $2.50/kg = $22.50
Bituminous Coal = $13.6 kg @1.20/kg = $16.30
Metallurgical Coke = 14 kg (@ ??)
Charcoal = 13.6 kg @ $2.50/kg = $34.00

However, this does not accurately reflect actual consumption over a working period.
Although propane may appear to consume less, in fact over a given hour, considerably more propane is burned (a propane forge is on 100% continually). It also does not reach the same peak temperatures, so takes longer to reach forging temperatures. So coal consumption is actually lower over the same working task / time. Also with coal the air blast (so burn rate) on a coal fire is continually shifted on and off.  This beyond the clear reduction in ‘cost per hour’ for coal use.
This certainly may be balanced by mining and delivery costs - the coal is trucked up from West Virginia. Propane from my local farm co-op location.
So, in a typical year of operation, I normally consume the following totals :

Propane = 365 kg
Coal = 450 kg
Charcoal 135 kg

This makes for a total CO2 loading of  2,007 kg (so two metric tons CO2 = about 450 kg carbon )

* Charcoal could be utilized here as an alternative. Although the needed wood could be considered ‘renewable’, the creation of charcoal itself produces significant amounts of various green house gasses. Trees could be re-grown with enough time (decades), so potentially at least use of charcoal avoids releasing fossil carbon. There is considerable ‘low ball’ in these numbers. Charcoal does not produce a high a total temperature as the other fuels, so in fact takes longer to reach temperature, in turn effectively consuming more fuel per hour. In practical terms regardless, the raw cost of the needed volume of charcoal as a replacement makes too expensive as an alternative.

In comparison, I travel considerably related to my business operations. A typical year would see me consume about 3000 litres of gasoline, which itself generates roughly 7000 kg CO2. (About 1575 kg carbon!)


Given that I fully support the implementation of some form of ‘user pay’ carbon tax.

Given that my business related carbon loading is a total of an estimated 2025 kg (carbon). Of which 450 kg applies beyond gasoline use.

What is the intention of your Party, moving forward currently, or beyond winning the next election?

Importantly, how will this policy apply directly to my situation?

Thank you for your patience in wading through this message.

Darrell Markewitz
Wareham, Ontario (lower Grey County)

PS - A related secondary factor may be my use of a home wood stove.
My home, constructed in 1987 came equipped with electric baseboard heaters only. Living rurally, there is no natural gas available. I might be able to renovate for propane central heat, but the building would not easily accommodate this system, and the cost would be considerable.
I did install a air tight wood stove in the upstairs main living area, which easily cuts my yearly electric bill (seasonal heating aspect) by at least 50%.
I consume roughly 3/4 a standard bush cord (4 x 4 x 8) of hardwood each year to accomplish this.

Carbon cost??

If you read the last posting here 'Carbon Loading at Wareham', you can see where that raw data came from.

I sent a copy of this letter out to each of the four main parties here, to the Ontario and the Canadian levels (so Progressive Conservative / Liberal / New Democratic / Green) - a total of eight separate copies. This was done through the 'contact us' information on the individual party web sites. In most cases this function is a 'form fill' on that web site.

This was done on Monday February 26.

I got 'auto reply' responses (ie: 'Thank you for your inquiry') back that same day from: National NDP / Ontario NDP / Ontario PC.

It has now been two full weeks.


Now, I'm quite willing to cut the Ontario PC party some slack, given the mess they have been going through over the last two weeks!

But everyone else?
Beyond those few 'robo-responses' there has been nothing. 

(Especially GREEN - given that is is a core issue for your Party. And that I did send a second follow up to the local Ontario candidate directly.)

Thursday, March 08, 2018

Carbon Loading at Wareham

This is not the first time I have attempted to get some handle on the amount of Carbon Loading created by the Wareham Forge - and my own personal life :
(7/7/2008) Carbon and the Forge
(12/4/2015) Carbon Loading

Please take it as a statement of principle that I consider *my* generation (end of Baby Boomer) has been mindfully negligent, self indulgent and irresponsible in terms of the impact of our collective lifestyles on the Environment. 
Although I have little alternative to the use of fossil fuels for my chosen profession as Artisan Blacksmith, I clearly know that I must pay some cost for doing so.

CARBON at Wareham

Forge Fuels:

Propane = 365 kg
Coal = 450 kg
Charcoal 135 kg

This is a typical amount for my year’s operations.
- Coal is bituminous coal, source is West Virginia. It is shipped via truck to Robb Martin’s in Floridale (near Kitchener/Waterloo) and I drive down to get it from there. Typically I purchase about every 18 months.
- Charcoal is ‘Maple Leaf’, which is maple, produced in Quebec. It is purchased at my local Home Hardware.
- Propane is purchased at my local Co-Op, loaded into my own 40 lb cylinders.

Gasoline :

Two vehicles :
1998 Honda Odyssey / 2 litre x 4 cylinder @ 14,500 km
2008 Jeep Grand Cheroke / 3.6 litre x 6 cylinder @ 16,900 km
Total Consumption ≠ 3000 litres

The total fuel consumption given above is honestly a bit of a WAG. I took the total dollar amount for the year and divided by 1.10 (as the rough ‘average’ cost per litre over last year).
- In 2017, there was a major trip out to northern Newfoundland. This amounted to over 6000 km on its own. This kind of distance only happens once every 2 - 4 years.
- With travel to the USA now eliminated, it is expected that consumption for 2018 will be sharply reduced.

Air Travel :

For the last decade, there have been several business related trips to Scotland. Roughly every second year. Last year the flight was Toronto to Edinburgh / Aberdeen to Toronto.
Total Air Distance = 10,700 km

Air travel is a huge greenhouse gas generator. These working trips have all relied on grants or travel costs supported by the hosting institution. There is no air travel expected in 2018. Hopes are strong for a return to Scotland in 2019 however.

Other Carbon Loading

Workshop Consumables:

Includes tools, sundry items, materials, research related 
Total consumables = $7300 *

I have no realistic way to assess the carbon impact of my purchase of things like raw materials (primarily steel) or durable goods (tools, books) or disposables (paint, sandpaper).


In the workshop, I have several major electric tools:
- Compressor - 2 HP / 220v
- MIG Welder - 220v
- Hydraulic Press - 2 1/2 HP / 220v
- Table Saw - 1 1/2 HP / 220v
At best any of these are operated for 'less than 50 hours' over any given year.

As mentioned above, the building at Wareham uses electric baseboards.
Only a small part of the workshop is heated (!), about 200 square feet, with temperature set at roughly 8 C.
The main residence is roughly 1800 square feet, on two levels. The construction is basically frame with exterior wood planking, with 6 inch Fiberglas in the walls. The second floor ceiling has been upgraded to 10 inch Fiberglas. The main heating is controlled by two separate set back thermostats. The lower (studio / entry / library is normally set at 12 C. The upstairs great room is set at 12 nighttime, 18 day time. Of course the wood stove used on most days increases that temperature past the electric setting.
In addition there is an electric water heater (admittedly now 30 years old), with extra thermal wrapping.
One big electric element is the well pump (easily the highest use after heating).
All the major appliances are electric.

Total Electric Consumption = 11,000 kwh

Note that in Ontario, almost all the electric generation comes from nuclear (60%) or hydro (30%), with natural gas supplying only 8% of the total.

Wood Heating :

My home, constructed in 1987, came equipped with electric baseboard heaters only. Living rurally, there is no natural gas available. I might be able to renovate for propane central heat, but the building would not easily accommodate this system, and the cost would be considerable.
I did install a air tight wood stove in the upstairs main living area, which easily cuts my yearly electric bill (seasonal heating aspect) by at least 50%.
I consume roughly 3/4 a standard bush cord (4 x 4 x 8) of hardwood each year to accomplish this.
Wood Consumption ≠ 1090 kg

'Administration' Costs:

Some fractional amount would apply to things like:
- Communications (internet & phone service)
- Bank service charges, mortgage
- Insurance (business / home / health)

I have no realistic way to calculate my small element of the operations of Bell Canada, my bank, or my insurance broker.  Some calculators place huge carbon loading on to things like mortgage payment amounts (??)

Personal Purchases:

Into late middle age, the number of personal purchases I make is extremely limited:
- Electronics are only replaced as they fail (as infrequently as possible!).
- Clothing as it wears out (mostly work clothes, typically second hand).
- I am almost legendary for ‘shopping at the dump’, the majority of household items are scrounged, second hand or self built.
- Food purchases may be an element here.
Typical monthly food expenditure is about $250 / $3000 yearly (and that is for two of us)
Total Personal Expenditures (all purposes) = $4700

One carbon footprint calculator placed my total amounts at consuming 35% ABOVE the average for other residents of Ontario. Others have suggested that my loading is considerably BELOW the average.

If any readers can suggest a useful - and realistically accurate - carbon footprint calculator - I would certainly appreciate a reference!

* 2017 figures used throughout

Monday, March 05, 2018

.. the BIG BOX (Jay has on stage!)

As an addition to the recent series about Hammers for Blacksmithing -

Putting together a basic tool box

 This is what I set up for each of the student tool sets at the Wareham Forge:

Note :
- The hammers and tongs are selected to conform to the types of projects used in the courses provided at the Wareham Forge
- The problem (expense and availability) of equipping a total of six student work stations means there can be considerable variation in detail between the individual tools supplied to each box.
- The boxes are colour coded to specific anvils. The contained tools are also colour coded. This done primarily to match hardie tools to the specific (differing) hardie hole sizes. A secondary result is ease of sorting and packing up.

these images are very roughly to the same scale

Hammers : (B to T)
- 1 1/2 lb ball peen
- 800 gm cross peen - usually two different styles
- 1000 gm cross peen
• There is considerable variation between the exact style and weights between the various boxes (see the earlier post on hammer styles). This allows to switch around hammers in this general class for the best fit for each student.
• The 800 gm is suitable for the course work for most students, some will want to use the heavier 1000 gm.
• The 1500 gm is included primarily for use in the ‘layered steel’ / ‘bloomery iron’ courses.

Tongs : (B to T)
- 1/8 flat
- 1/4 square / round - ‘toms tongs’
- 3/16 flat
- 3/8 square

Hardies : (L to R)
- hold down
- cut off (most of these of mild steel, to reduce possible hammer face damage)
- bick
- bottom fuller

Wrenches * : (B to T)
- linesman
- needle nose
- vice grip (although use is not suggested)
- adjustable twisting wrench
- square bar twisting wrench

Punches : (B to T)
- centre punch
- round hole / drift
- straight cut
the remainder are random to various boxes (used for decorative punching)
- flat oval
- blunt round
- flat curve

Other tools : (B to T)
- rough file
- anvil devil
- wire brush
- bending fork
- spring shouldering tool

Everything seen above does fit into a standard metal tool box

Safety (not shown)
- basic polycarbonate glasses
- insert foam plugs
- light leather gloves
- leather apron

Additional (available in the workshop, but not in individual boxes)
- tape measure
- small square (adjustable, 90 + 45)
- scribe
- soapstone / silver pencil

* Thanks to Vandy for spotting the typo there. 
No, 'Wenches' / Dancing Boys are NOT supplied!

Friday, March 02, 2018

Getting HAMMERED - #3 Setting Up

Number three in a series :
Follows up from yesterday's post : (effects of hammer profiles)
and Wednesday's post : (looking at hammer shapes)

When you get a hammer as brand new - it is not ready to use.
We had discussed how individual head shapes and weights suit different individuals.
This is even more true for the handle of any hammer.

First thing: Look at the working face and peen edges.

Most new modern hammers will have been either cast or drop forged to make the metal head. (If you spent some huge amount for a 'custom profile', the head might have been hand forged?) This rough form is then polished on the face and peen end.
Most typical is to create a flat surface, with some amount of 45 degree bevel around the edges.

Left - brand new Italian / Right 'antique' Engineer's
In the image above I picked two hammers that had roughly the same shape and roughly the same sized faces.
You can clearly see the sharp edges to the manufacturer's bevel on the left hand (brand new) hammer.
The other has been set up correctly for use (in this case also a good long working life!) What you want to do is gently round off those sharp edges. If you don't, you are going to find that even with a dead flat impact stroke, each blow is going to leave a crescent shaped cut into the soft metal. This will become a serious problem if you start forging with the edges (normally done to more quickly sculpt the metal into shape).
Remember that this also applies to the peen side of the hammer.
I personally undertake this rounding of the factory edges with a fine belt sander, but a fine tooth file would work equally well.

Second thing : Change that handle!

My primary forging hammer with two new handles (click for life size)
• The ideal material for a forging hammer handle is ash or hickory wood, with a clear, dead straight grain.
• Fiberglas is seen as a substitute for wood. I personally find Fiberglas handles 'whippy', jumping up on the return stroke and thus more difficult to control. This does indicate good energy return from the stroke however, so your opinion may differ.
• Plastic handles are now found on cheap 'China' hammers. I personally find plastic handles almost completely impossible to use. With all plastic, the return bounce from any stroke can go almost anywhere. This makes it almost impossible to maintain any uniform rhythm, and also very difficult to control your aim between individual strokes.
• Plastic / Fiberglas core? I did purchase one of these, recently available on Mechanic's ball peen and hand sledge hammers. As I don't often work with the profile / weight of the sample, I can't reasonably offer an opinion here. I strongly suspect the result will be something between all Fiberglas or all plastic = not acceptable.
Note that 'all metal' handles are NEVER found on forging hammers (although seen on construction framer's hammers). For good reason. The shock effect on impact would be massive, with the amount of rebound from a stroke almost absent.
I have seen some 'fiberglass with metal core' handles, again on mechanics profile hammers. Again I don't expect those to function well for forging.

Above are seen two easily available replacement wood handles - at least here in Canada.
Top - from Princess Auto - Engineer's Hammer Handle
available as 14 inch ($10 at writing) and 16 inch ($13 at writing, seen above)
Marked 'Made in USA' *
Bottom - from Home Hardware - Benchmark Replacement Handle
available as 16 inch ($13 at writing) *

Now - look at the shape of the two new replacement handles (or on any new hammer) - compare with how my main forging hammer has been set up:

Setting up a new handle (click for life size)

In the comments above, you see continual reference to two primary aspects : Reduction of Impact Shock
Energy Return / Lift
You notice how the two aspects are directly linked to each other.

I maintain that reduction of impact shock is critical.
Impact shock goes right into your joints, most especially your elbow. One jolt per stroke. How many strokes in a heat cycle? In a forging session? Over a life time?
Obviously even a very small reduction in impact shock becomes massively important over the long term.
Consider energy return. Even a small increase in the natural 'bounce' return on each individual stroke again is multiplied by the huge number of individual strokes made. If that energy is not returned to the hammer, it will be your muscles contributing the difference.

So - when you examine the new handles, you see the wood is thickened, just below the head, just before the shaft diameter. Why? Because this is typically where a handle will break. Handles are manufactured this way to 'make them last longer'. But thickening the shaft also makes the handle more rigid = more shock + less bounce.
You can see that I thin out the wood below the head, down to the minimum diameter of the shaft - and along the entire shaft length. This *absolutely* shortens the effective working life of the handle. I typically get 18 - 24 months use out of one of the indicated handles before it breaks and needs to be replaced.
** What does a replacement elbow cost? **

Any new handle will have either paint or lacquer on it (done to keep them looking clean in storage).
At a bare minimum, you will want to remove the coating down to bare wood. This is because that coating will hold moisture from perspiration onto your palm. If the skin gets damp, it will soften. If it is soft, you are likely to get blisters. Most certainly you will not be able to work with painful (!) torn open blisters. (Note that as you work more and more, your skin is going to toughen. Eventually your hands will likely stop sweating at all.)

Remember the discussion on suiting total handle length from yesterday?
Cut the handle down to suit your body size.
(more on this below)

The next important alteration is to shape the handle to your individual grip. This will be a combination of diameter, and shape.
Diameter is largely based on your actual hand size, a combination of palm and finger length and thickness. (Mine is 8 inches / 20 cm. I've mentioned Kelly, hers is 6 inches / 15 cm. Obviously, we need quite different diameters to our hand grip section of a handle!) Just grab the handle (after the head is attached ideally) and keep modifying it until it feels comfortable.
Shape is based on grip strength. For most people this will be some oval cross section. You will find a perfectly round handle hard to control. You can not 'feel' where the head is positioned, and a round handle tends to shift (rotate slightly) on the return bounce. These days my joints are stiffening (arthritis from all those hammer stokes!) and I find I need a very flat sided shape to really grip and control the hammer.

Now, I also apply some tape to the working handle.

I suggest for new students that they apply a simple loop of tape marking the correct grip point on the handle. Note that this on the far end of the handle.
The purpose of this tape is to remind you to keep your hand grip at the correct place on the handle.
If you find you are constantly sifting your grip forward down the handle towards the head - there is something wrong with this hammer - for you personally.
Get a different hammer! Most commonly this means the handle grip section is not comfortable (diameter and shape). It may mean that the head profile, thus dynamic in motion, is just wrong for you. It may additionally mean the tool is simply too heavy for you to correctly control.

I usually run a length of spiral wrap down just below the head, about 3 or 4 inches (7 - 10 cm). I will sometimes first use a layer of aluminium metal duct repair tape, always followed by good old hockey tape.
There are two reasons here. I find that when I'm making large sweeping curves, especially complex shapes that involve me really leaning over the horn, well , sometimes I do miss. That layer of tape protects the top of the handle from damage if I end up missing and hitting the top of the handle against hot metal. (That is why electrical tape is a bad choice!) I regularly put aluminium tape on to ball peen and crowned hammers, which I use for hot dishing sheet. The reflected heat off a piece of sheet at forging temperatures is incredible, and this just helps protect the wood . (I did actually have a handle catch fire one time!)

Remember that bit about damp hands? My skin is toughened and so dried out that my hands don't actually sweat any more.
This is important as it relates to the red tape surface seen over the handle grip. This is a self sticking silicone rubber tape sold for making quick plumbing repairs. I apply a double layer thick wrap of this to all my personal working hammers. The effect is to create a slight shock absorbing layer over the handle.
This tape can be purchased from sources like Lee Valley Tools, (at writing $12 - it now comes in colours!), one roll I get three hammers worth. The application is not extremely durable, I find I have to replace it about every 12 months.

* Be careful about the marking 'Genuine Hickory'!
The Benchmark handles were originally made in the USA - of *American* Hickory. Recently these have been sourced from China, still marked 'Genuine Hickory'. 
I had checked this out when my last purchased handle just did not perform as I expected. The handle was too rigid (both increasing shock and reducing bounce height). I found out that there *is* a species known as 'Chinese Hickory'. It obviously does not have the same mechanical properties - as are required.
Home Hardware does have an alternative available : '16 inch Blacksmith's Hammer Handle (listed at $12). I have just ordered two from this new supplier to check on the quality.

Thursday, March 01, 2018

Getting HAMMERED # 2 - Dynamics

Number two in a series :
Follows up from yesterday's post (looking at hammer shapes)

So - I had illustrated a number of the wide range of hammers, even in the same weight class, I keep here at the Wareham Forge.

I have a total of SEVEN hammers held in a basket, attached right at the anvil stub:
• my primary hammer (800 gm 'Engineer's')
• two rounding hammers (800 / 1000 gm 'Diamond')
• two wider cross peens (800 / 1000 gm 'Antique Farrier's')
• two heaver, sharp cross peens (1000 / 1500 gm 'Classic'
I have about another 10 more specialist hammers along the edge of the forge table. This includes various straight peen, ball peen, diagonal peen - with variations of weight / aggressiveness of peen. Plus a couple of replica Viking Age hammers. All those don't get used all that often, but are still close to hand.

What elements effect the dynamics of any given hammer?

click for roughly life size view

Here you see a comparison between a Swedish and 'Diamond' pattern. These two hammers that are the most different in the elements under discussion, plus my primary hammer (Engineer's). All three are 800 gms.

A - Distance of striking surface (face) from centre line
Swedish = 5.5 cm
Diamond = 4 cm
Engineer's = 6 cm

B - Mass distribution around centre line - head / core / peen - % (estimated)
Swedish ≠ 45 / 35 / 20
Diamond ≠ 30 / 40 / 30
Engineer's ≠ 40 / 40 / 20

Both of these elements, taken together, define the 'snap' against 'balance' as the hammer moves through the air.

A hammer with more of its mass forward the face, will tend to suddenly jump forward, as you swing it from vertical (starting position) to 90 degrees (striking the anvil).
This will accelerate the head, increasing the energy of the impact. *
However, this sudden 'snap' also puts increased strain on to the joints of the user, especially the elbow. (The 'French' pattern, with so much weight on the face side, is especially extreme in this effect.)

A hammer that has its mass centred on the handle will remain extremely balanced as it moves through the swing = better aim. This may reduce the possible impact energy of the stroke, but most importantly, it will greatly increase the ability to control not only the point of impact, but also the angle of the face when it strikes. The best example of this is the 'Hofi' pattern, which is perfectly balanced (1/3 to 1/3 to 1/3. With that hammer you can set an angle, then drop it - it will be in exactly the same angle (pitch and yaw) when it strikes the floor!)

Both are extremely critical in my opinion : "It don't matter how HARD you hit - if you MISS."

Both of these factors, balance and snap, will importantly effect individuals differently, largely based on physical size and strength.
Note here that these are NOT the same thing at all. Someone with a 'robust' bone frame, is not automatically strong - just as someone light of build is not necessarily 'weak'. That being said, the truth is that muscles can cushion bones and joints, but in turn can only prevent shock to a certain amount.

C - Handle length
Swedish = 35 cm
Diamond = 32.5 cm
Engineer's = 38.5 cm

The 'ideal' effective length for a hammer handle is based on the physical dimensions of the user. (This is simple ergonomics, the principle applies to swords, golf clubs, ... Almost any tool used in motion needs to be fitted to the individual body measurements.) *
The classic method to determine this 'ideal' is to place the butt end of the hammer on to the crook of your elbow, with your arm extended up, with fingers outstretched. The top edge if the head, hammer resting and extended along your forearm, should match the tips of those fingers.
(In my case, I have extremely long arms - thus the considerably longer than normal handle length. I find I just can not develop much impact force with the Diamond, although it is the same * mass * as my Engineer's. My partner Kelly, who is all of 4 foot 10 inches tall, uses one of the Diamonds as her primary hammer - at loves it.)

Next up - Fitting that Handle

* I may address the raw physics of hammer motion / energy in a further posting.


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