Illustrations of Forge Welding

 ‘Don’t try this at home kids!’

This piece originally written for the Iron Trillium - Ontario Artist Blacksmith Association

This is the start of my current discontent :

On an estimate, this stack appears about 1 wide by about 3 1/2 + tall by 10 + inches long. (1)

Do any of you see the potential problems here?

I had made a general comment after that first image was posted up on the open discussion :

“ (curious) Are you using a press? Otherwise don't you have problems with the layers 'humping' (*) and making gaps, as you hammer towards the rigidly fixed sections? “

And guess what?
Later there were questions asked ; ‘ Why where there de-laminations of the forge weld? ‘ Which were (predictably) shown to the far end of the billet, to the outer portion of one side. Yes, this was hand hammered (there was a video clip added later as well). Honestly, I considered the hammer choice and the technique shown was just - well, pretty bad (and most likely to aggravate the ‘humping’ problem I mentioned).

Observation # 1 : Don’t believe what you see on the internet. 

Remember that ’90 % of everything is Junk’. (2)

Here is the thing :
You do want to use some method to hold the pile of strips together.
Yes - there is that traditional Japanese approach, where you have what is basically a paddle (rectangular piece on a handle), on which you place a loose pile of plates or pieces. Then oh so carefully heat, then lift over to the anvil, striking with a very wide faced (specialized) hammer to weld. Using great skill not to jumble (much less drop) any of the small pieces.

I learned to prepare my stacks well before I ever had access to a modern electric welder, using several wraps of wire to hold the pieces together. This of course meant I had to pull off the wire loops after the first tack weld course. The wires would certainly weld into the top and bottom surfaces, but would end up bulging out and off the sides. Yes, you do have to use some extra care when heating to welding temperature, that you don’t just burn the wires away. (I find plain ‘black’ electric fencing wire ideal here.) Yes, this certainly adds an extra step, fixing the welded block in the vice and ripping the fragments of wire off. 

An extension of this method would be using a box shaped collar, which would be knocked free once one end of the billet was at least tack welded. (3)

These days, truth be told, I have a big MIG welder, and I usually run a bead fusing one end of the stack together - and also at the same time applying a long bar as a working handle. I personally do this along one end of the plates, not multiples down the sides as seen above. This because the MIG process will ’smear’ the metals combined in the stack, which I certainly don’t what contained in the final layered billet. In practice, I’ve found that I usually get some cracks in the welded pile where the handle is attached anyway. (This primarily because the handle itself acts as a cold shunt.)

Here two pieces of flattened iron bloom, MIG welded to a handle

Fixing the pile at one end, allows you to run your hammer blows from that point down and away to the open end. This will squeeze out excess flux, and importantly any remaining oxide or dirt, as you hammer from centre to edges, working sequentially down the stack.

Look at the measurements of the stack in that first image yet again :

• Ideally you want your stack of plates to be *square* in cross section - the height of the stack being the same as the width of the individual bars. This is simply to make sure that you are getting even heat penetration throughout the the whole stack. (4) You can see quite clearly here that the starting stack is easily three, perhaps four times as tall as it is wide!
• Ideally you want the strips in your stack to be roughly the same width as your hammer face, or not that much wider. (Does not necessarily appear a problem here.) This so you can quickly, and effectively, overlap individual hammer strokes. This to both ensure all parts of the stack get effective hammering, but also to ensure you squeeze out that same flux / impurities from between the plates.
• Ideally you want to limit the overall length of your prepared pile. There are two reasons here. First is to ensure that the whole pile will come up to both the correct, and importantly a uniform, temperature suitable for effective welding. (In this case, it was later shown the individual was employing a propane gas forge. There are other potential problems / method adjustments required for effective welding in a gas forge. One clear advantage is that in a well designed unit, typically internal temperatures are quite even throughout.) (5)
• The second reason to reduce the length of your starting stack is simply based on ‘how fast can you hammer’? Remember that your stack, especially for that first weld, is rapidly cooling as soon as it leave the forge. The outer layers especially. Even more so the bottom most ones, in contact with the cold anvil. You can mitigate this somewhat by letting the most distant part of the stack hang off the anvil, pulling the stack back towards you as you hammer, more or less in the same spot. (So moving the billet, not chasing the hammer over the surface.) But any way you look at it, you can only work so fast! I would expect anyone would find the temperature would have significantly dropped before they would reach the end of such a long stack (6).

This all suggests that there potentially would be welding flaws most likely to be found to the far end of the stack (away from the handle) and towards the outer surfaces, especially to what ever surface was placed down to the anvil.  ( Guess what ended up happening here? )

( * ) ’Humping’

Ideally you would want to start on the part of the stack closest to you, pushing any flux / debris out of the layers and squirting this away from your body. Because the top layers are directly under the hammer, these distort the most, certainly more than the bottom layers (where the force has to be distributed down through the loose stack of plates. This is going to effectively cause those upper plates to stretch longer than those at the bottom. If you have fixed by welding at this starting point (or have a loosely held wire bundle) This does not present much of a problem. But if you have secured the entire stack with multiple weld lines as seen, what will happen is that as those top layers are effectively forced longer, they will shift forward and then bulge away from the lower plates. If you worked extremely fast, with very careful control of the hammer striking angle, you might be able to both limit and adjust for this as it happens. But given that there is no functional reason (that I can think of) for running multiple securing MIG beads to begin with? ( 7 )

I should also mention (although you must believe me here, see note 1) that in the short video showing the initial weld sequence, the hammer technique is, well, questionable (at best). The smith is striking with the hammer at  a pronounced diagonal stroke. This is certain to impact more distortion force to the upper plates. If the hammer was coming in flat, at least the force would be directed straight down through the entire stack, rather than squeezing the plates forward. Additionally, the physical motion shown is simply horrible. The smith is striking with the left side edge of the hammer, arm away from the body, elbow lifted. This creates a kind of sweeping motion, rolling the wrist. And using what certainly looks like a 1.5 to 2 kg hammer (?).

'Hero' shot of me forge welding (actually a billet of bloomery iron being compacted).

My own experience has been that for the best results, is to run at least two (ideally four) welding courses. I first use the lighter, better controlled, and way faster, 800 gm hammer. I will usually do this twice, giving both the top, then the original bottom, surface a chance to be ‘up’. I consider these to be ‘tack’ welds, securing the individual plates together. Next I will repeat this combination, switching to a ‘next heavier’ hammer (for me this the 1000 gm - I find I can’t move the 1500 with enough speed or control). This ensures deep penetration and sold welding through the entire block.  (Again your mileage may vary here)

Over the years, there has been a LOT of discussion on ‘the right way to forge weld’. Frankly ‘It works for me’ may be the most common statement. There is some science behind this (not what most people think, either). Working *clean* is most certainly the best single piece of advise.
(see a blog post )


Right now I think we all are seeing an absolute explosion of people thinking that now is the perfect time to attempt to turn their hobby into a ‘paying business’. Throwing money into high powered equipment, in place of developing any hand skills. There is a possibility that for a very, very small number, this might actually succeed. Knife *making* (7) is most certainly the ‘flavour of the month’. I’d bet this also annoys OABA members who have been forging blades for years.


1) I’ve specifically chosen not to credit the individual who provided this image, or the later process images / descriptions. (This to remove any possibility of bad feelings over my opinion - this is not from anyone in OABA, or even Ontario btw.)

2) ‘Sturgeon’s Law’ : coined by science fiction author Theodore Sturgeon

3) If you look at Scott Lankton’s several publications describing the making of his Sutton Hoo sword replica, you will see this use of sliding collars.  (available as a pdf)

4) It is actually a bit more complicated that this. The differing carbon contents / alloy composition of the individual bars may also have slightly different ideal welding temperatures. Ideally you want to place either ’sacrificial’ strips, or the metal with the greatest tolerance against overheating, on the outsides (top and bottom).

5) I personally learned to forge weld in a ‘traditional’ coal forge - and continue to this day using coal as my primary method. The size of my fire box has been found to be most effective for welding billets up to at most 6 inches long. My normal starting stacks are roughly 1 1/4 x 1 1/4 x 5 inches long, which I find gives me the best results (your mileage may vary!).

6) Any of you who have seen me demonstrate certainly have noticed that my normal stroke rate is about double of most people. (This due to the ‘high and fast’ circular motion / technique that I use.) Again I find that for anything over about 5 - 6 inches, even this fast method will  just not allow enough time to place the correct sequence of blows over the surface, before the metal has dropped below what I consider an effective welding temperature. (again, your mileage my vary!)

7) On later reflection, there is a possibility that occurred to me, coming from the use of the propane forge. The tight clamping and securing the individual plates may be an attempt to limit oxygen penetration onto the inner surfaces of the plates. (We all know that an oxide scale surface will not weld?) There are a number of reasons that I personally do not consider gas forges ideal for welding. Individual experience is most likely to differ (Good equipment design a critical factor). I will suggest that binding plates together is not a substitute for correct use of a fluxing agent.

8) I (strongly) distinguish between ‘knife making’ (grinding bars to shape and adding handles) and ‘blade smithing’ (forging bars to close profile). This becomes especially clear with much  seen of recent layered steel blades. Billets that have been hand forged will show distortions from this process, which is part of their specific character. Surfaces with geometrically perfect lines obviously have to be ground to shape (often from purchased billets, themselves created using presses).
More fuel for the ‘that’s not blacksmithing’ debate ?

the Labrys - Considering an object

From a recent e-mail :

 I'm looking to get a labry made, obviously custom, as a female I'm looking for something made for full functionality and usability to last for as long as time would allow, eventually to be passed down to my grandsons ... can you give me an estimate of what I'm looking to be spending.?  (1)

I had to look up 'labrys' : https://en.wikipedia.org/wiki/Labrys

Golden minoan labrys ( double ax ) Archaeological Museum in Herakleion.  (2)

Although you do always have to be careful with the short hand of Wikipedia, the article does match pretty much what I did know generally about double bladed axes in archaeology. Mainly that these rarely existed as objects, and when they did, they were certainly ritual / religious symbols rather than functioning weapons. There are existing (ancient) depictions of the labrys, but these are initially related to goddess figures (so the proportions are clearly unrealistic). 

Modern fantasy artists (blame Frank Frazetta) have often included axes of various kinds - but again there is little realism in the sizes seen. 

'The Snow Giants' Frazetta - 1967

There is an aspect of physical dynamics involved in the 'real' over the 'fantastic'. Even with a long double hand handle, any axe much over 2 kg just can not be controlled in movement. This is certainly proven if you look to Viking Age axes, a time period (particularly from Denmark) when axes became commonly used in combat. Or to lumbering tools from the Canadian Settlement period.
(see a blog commentary related to a different artifact axe)

So one clear decision point for anyone will be to determine if they are desiring what is more a symbolic than a functional object.
(In this case, 'Full functionality' may present a bit of an interpretation problem.)


I usually suggest people take a comparison look at the line of axes made by Gransfors Bruk of Sweden. This company has a long history of forging high quality tool axes. (3) They do make an extremely high quality product, typically mild steel bodies with inlaid carbon steel cutting edges. (I have one of their 'forest axes' myself - and it is an excellent tool.)

the Gransfors Double Bit Axe

 

Functional double bit axes were common in the 1800's in North America as a standard logging tool. The two edges had slightly different bevel angles, allowing for use for both felling and splitting. You can see G/B offers one, in modern times more commonly used for competition axe throwing (which has been popular the last decade). 
You can see the important details :
- head weight = 2 kg
- blade length = 16 cm
- cost = $480 CDN (plus shipping, any duty)

In actual fact, the closest comparisons available at G/B will be found on their (limited) 'Ancient' line - replicas of Viking Age working tool axes.
 
You can see two examples there, the bearded axe and the (smaller) double lug axe.

Gransfors Double Lug Axe, showing slit eye construction

From the descriptions, the bearded axe is likely the closest to ideal - as these are individually hand forged - and specifically mention an inset carbon steel edge
- head weight = 1.3 kg
- blade length = (not given, but likely in the range of 15 cm)
- cost = $1450 CDN (plus shipping, any duty) 

Gransfors Bearded Axe, showing punched eye construction

 

So - this is the 'standard' for a roughly similar type. Creating a double edge (over a shaped then punched eye, single edge) represents both a different method - and certainly additional work / time (two inset edges to weld and shape).
A rough ball park quote for this specific request (Labrys type) is hard to generate, because exact details on size have not been established.
But *expect in the range of $1500 - $2000 CDN* (plus required HST, shipping)


Now I will warn you that I am certain there are certainly 'wall hanger' versions available - what are basically nothing more than costume pieces. At *best* cast steel heads, if even a size to be realistic in handling. (More likely cast aluminum for wide edges / large heads like seen in films). These things are not actual working tools (despite what may be claimed). If your interest is the visual / ritual aspect, those may suit? 

16 ga (1.5 mm) stainless steel; Viking-style etched pattern; Hollow inside; Double head width - 16 1/8 in (41 cm) Double head heigh - 13 in (33 cm)

Source: https://armstreet.com/store/armoury/fantasy-viking-double-head-axe

'Fantasy Viking Double-Headed Axe' : Hollow stainless sheet, 40 x 33 cm (4)

I would caution you to really look closely at the description and especially the construction details of cheap (mass produced!) products offered. (Taking two pieces of cut out mild steel, then MIG welding these to a section of pipe, may be fine for a Halloween costume - but this is not 'real' in any stretch of the imagination.) 

'Labrys Double Headed Axe' : Cut sheet welded to pipe

Readers who wish to read further commentaries about past axe making projects by the Wareham Forge will find any number here on this blog :

Norse Woodworking Axes
VA Ship Tools - Adze & Broadaxe
French Trade Axe from Bloom Iron
Ship Tools - Adze / Broadaxe

Images are direct links from the indicated web sites

1) Intentionally hiding the original sender. I do warn people, with a tag line at the bottom of any e-mail, that : " To those receiving long detailed replies to specific questions : My own written response may be edited and re-used as a blog posting. "

2) Image by Wolfgang Sauber (linked from Wikipedia) 

3) I would dispute their definition of their main line of products as 'hand' forged, in fact they have designed (and long used) specialized mechanical hammers and dies. This is a massive investment, but also allows them to fairly quickly produce standardized shapes (with little to no actual hand hammering). (see their web site description ) Note that this does not apply to the 'Ancient Line' discussed later here. Those are individually worked by hand hammering.

4) This object is described as " Forged out of genuine stainless steel ..."

Increasingly the technical term 'forged' is being used to mean 'made'. This is absolutely incorrect - and I consider the worst kind of commercial hype. As the Webster Dictionary also defines 'forged' as : "made falsely especially with intent to deceive" - you do have to wonder!

Prototyping

I've commented here before on the 'Iron Triangle' (1). Over the years of this blog, there have been a lot of commentaries related to the 'Artisan's Way' : where ideas come from, and how these get fleshed out from Inspiration, to Concept, to Making.  There have been discussions of the many, many facets that any individual must undertake (and usually attempt to become proficient at) to turn an occasional hobby activity, into a self supporting business. 

This segment is going to take a look at something so often completely forgotten in the creation process - prototyping. 

There is an old parable. The Japanese master was asked : How long does it take you to make a tea bowl? His answer : Twenty minutes to make the bowl. Twenty hours to prepare the materials. Twenty years to learn how. 

Now too often in our modern world, all people see is the 20 minutes. True master's skill looks effortless. People who do not work with their hands do not recognize the endless effort that is required to acquire that level of knowledge, skill and experience. (2) 

In a perfect situation, an Artisan would have some huge stockpile of Knowledge, Skill and Experience that would allow them to effortlessly (??) to select and transform raw materials into a given object.

 

But let me tell you - that is just NOT how it works.

 

I had a very loose concept for a large sculptural piece, centered around a large green glass wine carboy I had scrounged years back. I was thinking of a kind of fantastic 'Audry Two' plant form, with the curved flask shape, turned upside down at it's heart. In working out the overall form, I was intending to make a number of tall S shaped elements, using a number of the glass 'bell' jars I had purchased a long time back. (3)

Initial 'hen scratch' concept drawings

This glass flask was quite large, about 45 cm ( * ) at its widest and about 60 cm tall. Unfortunately, the years being stored in the unheated workshop had placed a huge amount of stress into the thin glass. While I was tracing around the piece to create a full sized layout, the vibration of my arm over the surface proved enough to crack off the entire base section of the flask. Obviously I will have to come up with quite different overall design from the initial concept.

I have often poured through 'Art Forms in the Plant World', which is a shortened overview of the work of photographer Karl Blossfeldt (4). With the loss of the large flask, I knew I would have to include some additional organic elements beside the bell jar 'flowers'

Image by Karl Blossfeldt

One of the images I have been stuck by is the one above. Described as 'Common Chili-nettle. Seminal capsules'. The source image is roughly 23 cm tall, 'enlarged 4.5 times', which would make the actual plant segments about 5 cm long. 

Those who have followed my past work have seen I have done a lot of pieces where my starting materials have been structural steel : pipe, angle and channel. Angle, when flattened, easily creates an initial stock with a raised central rib on ones side (and corresponding central depressed line on the opposite). I know this would prove a very simple way to mimic the scalloped surface on the outer, twisted, capsule parts of the seed pod. 

Although there was not clear detail of the interior parts of the seed pods, it was clear that there was some kind of shaped surface inside. This would only be glimpsed at through the gaps in the exterior spiral casings. Even still, including some kind of additional detail to the form I considered important, in terms of creating different visuals at differing viewing distances for the observer. (5)

The central rod shape, which would extend to make the final terminal, was chosen as 1/2 inch ( * ) round stock. As seen in the source image, this would end in some kind of pointed shape, with a taper drawn down towards it. I made a first attempt at this, using an slightly upset point, which was then hammered into a triangle shaped bottom tool. This resulted in a more or less leaf shaped, but three lobed form, flattened to one surface. I was able to make a more or less tri-symetrical shape by using a rounded edge straight line punch, forcing the flat side back into a gap left in the vice. In the end I was not happy with the overall result however. 

So I made a second version, this time starting with a longer square point. I then punched in a line down each of the flat sides of the square as an additional detail. I had started with a fairly generous length, but had cut off the first terminal made, leaving me with about 50 cm of material.

Start of the core part

The first idea I had for creating the core portion was to start with three pieces of smaller angle (1/2 x 1/2 x 1/8 thick) cut to 20 cm length. These were tack welded (admittedly fairly rough!) in three places, both edges, to splay out from the central rod. For the prototype, I used a simple 'cheat' on the ends, just cutting diagonal lines with the band saw for the ends. The lower portion were cuts at about 45, the upper a longer taper. 

Core - twisted

My idea for all this was to twist the fabricated bundle. Nice *idea* - but how exactly do you *grab* that kind of shape? Holding the lower edge (first cooling the bottom 3 cm or so) proved easy enough. Getting a secure grip on the *top* section to apply the considerable force required proved a real challenge. The overall shape presented by the three outward spreading V shapes of the angle was just too much like a cylinder, and my adjustable twisting wrench just kept slipping off! (6) In the end the result of three separate heat to twist attempts was only a 1/3 rotation, as seen above. (With the addition of considerable swearing in process.)

Preparing the outer wrap parts

For the outside wraps of the capsule, I prepared three pieces of wider (3/4 x 3/4 x 1/8) angle, each 40 cm. Again the ends were diagonal cut on the band saw. Here one end (the lower) was pointed to about 45, but the upper was cut to create a reversed shape (so from the ends back towards the center). Then each was flattened, but leaving about 5 cm on the lower end left at the starting 90 degree shape of the angle. These ends were then forged to both offset that tip to about 65 degrees, but also to add a Z shaped offset. (Clearer in the image above?) These pieces were then MIG welded around the lower end of the twisted core bundle. 

Forming the outer capsule

After attaching the outer pieces, the resulting splayed construction was simply far to large to fit back into the forge ! (7) So although tedious and offering a quite different kind of heat application and control effect, I used my oxy-propane torch to apply sequential heat, allowing me to alternately twist around each of the three bands. I used a piece of larger diameter steel pipe as a central form. This allowed me to concentrate on keeping the spacing between the individual bands (fairly?) regular as I worked around and up. Of course on cooling the cylindrical wrapped bands, these tightened around the form. I had enough space at the base to fit a long piece of 3/8 against bottom edge of the pipe to drive it out. 

Completed seed pod element

The last step was forging in the upper part of the three outer wraps. This requires a lot of lighter, controlled blows, as all the pieces are being both pushed into, but also around, to the core as you forge them. You can clearly see the difference in shape caused by this process, creating more of an elliptical profile overall. These upper ends were left 'forge tight' rather than later being spot welded together.

Element mounted

For this project, I will be making the 'stems' of each element out of re-profiled channel (1/2 x 1 1/2 x 1/8 used for the prototype). There are two cuts made in the end to separate the three 'lines' for this element about 10 cm. For the prototype, each of these separate pieces were forged to slightly different shapes : spread wide then spiral curved (right above), flat offset to one side then an open spiral (left above), drawn to a long square point with reversal curve (back side out of view). The main run of the channel is forged using the cross peen along the wider bottom side, into a recessed half cylinder bottom tool. This results in curving that flat side, also narrowing the gap between the two shorter sides (so more of a wide U shape). Next the opposing sides are carefully forced downwards and around - until the original two open edges touch. The net result is a very organic, slightly distorted pinched cross section, with a visible seam line running along one side. 

For the initial prototype, the two elements (pod and stem) were joined by simply driving the tip of the core rod down into the central gap remaining in the stem and allowing to tighten on cooling.

 

The creation of a prototype, even from skilled and experienced hands, almost always indicates forging problems to solve and modifications required for a more elegant result :

• I will likely abandon the use of angle in the core bundle. It has proved too difficult to manipulate - and to control the shape generation. 
• Instead, I will switch to using a bundle of small round rods, still spiral wrapped around that central core. Buy individually cylindrical pointing the upper ends, I will be able to also create an additional element, suggesting flower stamens.
• The prototype illustrated how starting lengths for the bars needs to be adjusted if I want to retain the same proportions as the plant source. Ideally I would like this element to be considerably longer in relation to its width (as the source is). Using a ratio 'twice the length for the wraps as the core' proved correct for this version, but only a second prototype will show if this remains the case for a longer finished element.
• The bottom edge of the outer wraps were formed by simple diagonal cuts. To mimic the more slender lines of the plant, these pieces should really be forged to long tapers initially. 
• A bit more care needs to be taken controlling the spacing between the individual outer wraps as they are coiled around. It is only through these gaps that the details of the core shapes are glimpsed.  

 

An important consideration also is revealed here : The vast difference between 'one of a kind' artistic objects, and more standard, repetitive objects. I spent a total of four hours generating this prototype element. With the changes suggested, I will certainly need to make a second, hopefully not taking quite so long (and with considerably less frustration). This represents a huge gap in both effort, and time, between 'I think I can make that' and 'I've made that before'.  

Time is money. 

Skilled Time is expensive.

A couple of things to bear in mind...

 

( * ) In Canada, steel stocks still come primarily in Imperial (inches) sizes. In an attempt to keep 'up to date' length measurements here are given in current Metric dimensions (cm).

1) You can have it CHEAP, you can have it FAST, you can have it GOOD : pick ONE. 

2) Of late, increasingly I am finding that 'quick fix' methods are coming to dominate public perception. This of itself is hardly a new problem, especially in Western / North American culture (I clearly remember when Eastern Martial Arts caught the fascination of the general public in North America. Few caught the subtlety of 'If you can snatch the pebble from my hand' (although I'd bet most reading are familiar. increasingly, I am finding 'I saw it on the internet' becoming a standard statement of the source of 'knowledge'. I consider this almost frightening in implication, especially when coupled with the quite obvious increasing lack of 'critical evaluation' by the viewers. The number of YouTube hits someone has accumulate is absolutely no measure of anything, save perhaps 'instant celebrity'.

3) This illustrates the glass bell jars : 

'Glass Jar Holder' : 1997

 I had gotten these as a clearance item from Ikea, back in the late 1990's. There were a stock of these (at a stupid reduced price), in red / blue / green colours. I had bought ALL they had available. Currently I still have about 45 of these still boxed away!

4) 'Art Forms in the Plant World' is available as a Dover reprint. This a selection of the larger volumes of close up, fine detailed, black and white images :

https://www.goodreads.com/book/show/825481.Art_Forms_in_the_Plant_World

5) Going to stress this overall approach to design. Ideally any object will become much more interesting to the viewer if there are levels of differing 'visual information' to an object as one approaches from some distance. The overall lines will be seen from far away, ideally presenting enough flow that will encourage the viewer to come closer. At an intermediate distance, more of the form of the individual elements becomes seen (the shape of the flattened angle for example).  Closer still, and aspects like surface texture, or 'hidden' details (like the underlaying pod cores here) can be seen. 

6) In retrospect, some kind of special twisting tool, likely specific for this single application, would be needed. Likely a bar with a suitable sized punched hole in the center (to allow passage of the round core rod). Then three prongs attached, each spaced to fit down into the gap of each piece of angle. (??)

7) I certainly would have been able to correctly heat this large bundle in the coal forge - if I had been using it. I don't have any residual heat in my workshop, so by this time of year I switch to using propane when possible. As much for space heating as effective forging. (the 'Dark Side of the Forge' for me!)