Posts Tagged ‘Masthof Press Publishing’

An Ax Primer ~ My Thoughts on Choosing an Ax

Wednesday, January 26th, 2011

My personal Marble’s No. 10 Camp Axe. Produced between 1914 and 1943, the No. 10 was woodcraft writer and expert Bernard S. Mason’s favorite.

Good axes are the result of the combination of high-quality materials, fine craftsmanship, and good design. Some things to consider when choosing an ax are: 1) the forging method, 2) the steel and any treatment it has undergone, 3) the quality of craftsmanship, and 4) the kind and quality of handle it’s fitted with.

Note that in focusing on the desirable characteristics of good axes, I may give the impression that an ax that does not embody each and every one of these characteristics is an unworthy tool to be avoided.  Please understand that these characteristics are desirable traits to consider when comparing axes or different examples of the same model but that axes will have these characteristics in varying degrees.  Of course, some characteristics such as temper, head profile or head/handle alignment are very important to consider when shopping for an ax.  But remember – axes are not made to the same standards as custom collector knives.  Rarely will you encounter an ax featuring the best in materials, design, tempering and perfection in craftsmanship.  I’ve seen glaring imperfections in even the best, most expensive axes described here.   So don’t become too choosy or no ax will ever satisfy you.

Now let’s get started!

Forging ~

(Revised March, 12, 2013)

Forging refers to a method of shaping metal by means of applying force.  To say an ax is forged, means that an ax has been formed into a particular shape by hammer blows.  Forging is just one step in ax making.  The grinding, tempering, annealing, polishing and honing remain to be done.  Though folks often debate the merits of the different kinds of forging methods, in reality, the shaping process is far less important to the overall quality of an ax than what happens to the head once the general shape has been formed.

Axes have been produced by blacksmithing (human-powered hammer blows against an anvil), triphammer (automated) hammer forging, and drop forging.  Large-scale blacksmithing disappeared from the commercial ax manufactories over 150 years ago.  Only a handful of custom-made axes continue to be made by blacksmithing.  The introduction of the Swedish-made boutique axes in North America were the first to be made in a generation that were described as being “hand forged”.  In truth however, the Swedish axes are forged on a machine.  Some Swedish manufacturers forge their axes on a triphammer (also known as a smith hammer) and some on an open die drop forge (I have heard some are forged by the open die drop forge method but have not been able to confirm this).  Either way, they are forged on a machine.  Automated triphammer forging is nothing new.  Axe manufacturers replaced the blacksmith’s hand wielded hammer with that of the waterwheel-powered triphammer at least by 1828.

According to the Collins & Company records of that year, their new triphammers increased ax production to 10 axes per day for a foreman and striker (American Axes. Henry J. Kaufman, Mastoff Press Publishing, Morgantown, PA 1994).  Triphammers only provided the striking force for shaping the steel ingot.  The smith still had to skillfully move the ingot around on the anvil in order to shape the tool.  Small ax manufacturers used triphammers in the United States up through the 1960’s, long after drop forges were in use, not because they were inherently superior but because the small firms that used them could not afford to purchase a drop hammer in what was by then, a declining market.  Open die drop forging is very similar to triphammer forging.  Instead of a hammer surface striking the ingot, it is struck by a pair (top and bottom) of flat or slightly contoured dies.  Because the two dies are not connected, the material is allowed to expand out the sides.  Just as in using a triphammer, the ingot must be positioned in various ways to shape the ax head.  The skill involved in operating an open die drop forge is the same as that of triphammer forging.

Today, nearly all modern production axes are shaped by impression die drop forging (also known as closed die drop forging).  This method uses a die, or set of dies, shaped into a mold of the intended finished product.  A steel ingot is heated and placed on the lower die and is struck repeatedly by a falling hammer to force the steel into the mold.  Most modern ax makers use the impression die drop forging process and this is what most folks think of when they hear the term “drop forged”.

When did American ax manufacturers begin using the method?  Before most of your grandparents were born.  Though I cannot name a date with confidence, the Axe Manual of Peter McLaren (Peter McClaren and Fayette R. Plumb Inc., Philadelphia, PA, 1929), indicates that Plumb axes were all made by impression die drop forging by that time.  And the booklet did not describe the method as being a recent development.  Note that nearly all of the great American axes produced after the turn of the century, were made by impression die drop forging.  The speed and efficiency of the method allowed manufacturers to produce axes in large numbers with a minimum amount of labor, which lowers manufacturing costs and increases profit margins.  I say nearly all because a few ax makers in Maine continued to use triphammers into the 1960’s.  The early triphammers were attached to the end of an arm much like a hammer held in the hand.  These were called helve triphammers.  The modern Swedish axes are forged using a modern “drop” triphammer, which functions in the manner of the drop hammer used in drop forging.

Because the Swedish axes are said to be “hand forged”, many enthusiasts now consider production “hand forging” superior to drop forging, considering the later to be associated with cheap, undesirable axes.  However, that’s like believing that because all cheap automobiles are produced on a production line, all vehicles produced on a production line must therefore be cheap.  A common complaint of inexpensive drop forged axes is that they are too soft to hold an edge but that is due to their being “uniformly hardened”, a fault of the tempering method NOT of the forging method.

Is triphammer (or open die drop forging) better than impression die drop forging?  That’s debatable.  While it does take skill to forge an ax head with those methods, the quality of an ax is determined by what occurs to the head after it has been shaped.  It is true that both triphammer and open die drop forging are occasionally described as “smith forging” or “hand forging”.  However, Kauffman, a noted authority on axes, who held an MA in Industrial Arts and was a blacksmith in addition to serving as Professor of Industrial Arts at Millersville University, made a clear distinction between genuine hand forging and machine forging when he remarked “…because a triphammer functions in a manner very similar to a hand hammer, many axes of the nineteenth century appear to be a product of an earlier era; many are described by “experts” as hand-forged, when, in fact, they were forged on a machine.” (American Axes, Henry J. Kauffman, page 52).  Emphasis is mine.  Kauffman obviously did not consider a triphammer forged ax to be “hand forged”.  In addition, Kauffman makes no mention of any of the forging methods being superior to another.  In fact, in some ways, impression die drop forging is actually superior to triphammer or open die drop forging because it offers improved mechanical properties.

Why then, do the Swedish manufacturers choose to make axes by triphammer and/or open die drop forging?  The main reason is likely cost.  Impression die drop forging requires the added expense of tooling the die molds for every size and shape of ax that is offered in the line.  If a maker produces small numbers of axes or wants to change or add models frequently, then triphammer or open die drop forging are the most cost effective ways to do that.  Another, not insignificant reason, is to offer the added allure of a “hand forged” stamp on the head.  For more on forging, see here.

In Sweden, it is customary that a single smith not only forges each ax head, but that he makes the entire ax by performing every step of production, including the grinding, honing, and fitting the handle.  Thus, much more time is taken by an individual smith, to make each ax in Sweden.  While the quality of a Swedish ax head is not necessarily better than one made by impression die drop forging, the overall quality of the ax tends to be higher.  But that is only when comparing a boutique Swedish ax to a utility grade ax.  If the Swedish axes are compared to an ax of good design, and one which the maker sourced the best steel and handle stock, and took the extra time to grind, polish, hone and hang the axes to the same standard, there is absolutely no reason for it to be considered of lower quality.

The Steel and its Treatment ~

How an ax retains its edge is largely determined by the use of high quality steel and the treatment(s) employed by the maker. Axes aren’t hardened to the same degree that knife blades as they would be too brittle. Thus, they don’t need to be made from one of the modern “super” steels that knife maker’s use. You can trust that all domestic made and European axes will be of good steel. When most folks speak of “good steel”, they usually mean the ability of an ax to hold an edge well – and with the quality of the steels used today, that is the result of proper tempering NOT the steel. Tempering determines whether the ax is even worth considering. Sadly, as most modern axes are made for casual use, little time or money is spent on tempering. In general, nearly all inexpensive axes (including those of USA origin) are tempered to a single hardness throughout, being either too soft to hold an edge (most often encountered) or too hard to easily sharpen. This uniform hardness is not a good thing. Vintage axes featured a soft iron (or later, steel) head with a hard steel bit forge welded in. This produced an ax with a durable cutting edge but a head that was forgiving and durable. The better ax makers of today can accomplish the same thing by employing edge hardening technology (sometimes referred to as a heat treated cutting edge). If the head’s not painted, it’s often easy to see the “hardening line” that separates the hard edge from the softer steel. The edge hardening step could easily be done when making all axes but is often neglected to reduce costs.  Note that the depth to which ax makers harden the head vary widely.  Some harden the edge less than an inch deep while others go nearly two inches.  As you sharpen the edge you remove steel from this hardened zone.  So, if the zone is shallow, you will be left with no edge faster than if the zone is deep.  Even if you can see the hardening line, and even if it is deep, you do not know if the edge is hard enough to hold an edge or too hard, making it brittle and liable to break.  One way to test proper tempering is to run a file along the edge, as if to sharpen the ax. If the edge is too soft, the file will cause the edge to “roll over” in a thin flake. If the edge is too hard, the file will slide over the surface of the steel rather than “biting” into it.  If the steel begins to sharpen, the tempering is good. If a newly purchased ax fails this test, sell it at a garage sale.

Another steel treatment, somewhat related to tempering, is annealing. After tempering and cooling the ax, the head is placed in a warm oven (about 350-400 degrees) for approximately an hour. This relieves stresses in the steel created by the forging and tempering process and increases the hardness of the ax. Many consider annealing desirable because all vintage axes were annealed. However, annealing was important in the past because the steels of the period were relatively soft and had to be annealed for creating the strength required for a striking tool. Today’s alloys are much harder than what was available just 40 years ago, making annealing less important than it used to be. Still, Scandinavian axes makers continue to anneal their axes and this contributes to their allure.

The Grind ~

As important as tempering is an axe’s grind, which determines if it is suitable for its intended purpose. Most modern users are largely ignorant of the differences between ax grinds and how crucial this is to ax performance. If the ax is viewed from above, the shape of the ax grind can be evaluated. According to wilderness survival expert Mors Kochanski, the following grinds (shape from the eye to the edge of the ax) are associated with these uses:

1. slightly convexed face ~ general purpose ax
2. thick, strongly convexed face ~ splitting ax
3. concave face (may appear nearly hollow ground) ~ limbing ax
4. nearly straight face (tapering to a convexed edge) ~ produces an ax that glances least

Ax Profile Grinds

An ax with a slightly convex face will not bind in the cut, throws chips well and is stronger when using on frozen wood. If the face is too convex, it will not penetrate the wood to the depth required to make an efficient cut and results in a waste of energy. If the face is too concave, it will bind in the cut, resulting in having to always tug on the handle to release the bit. Eventually, this constant tugging will loosen the handle. If the grind is beveled improperly, the ax can dangerously bounce out of the cut, possibly striking the person wielding the ax. Overall thickness of the face-to-edge profile also contributes to ax performance. If this profile is too thick, the edge can never be made truly sharp; if too thin, the edge is likely to chip. Unfortunately, some grind profiles can’t be altered enough to be improved. For example, a profile that is especially concave can’t be fixed, as you can’t add metal back into the face. Even if the profile is good, if it’s too thin, it may not perform well and this can’t be changed. Of course, with time, effort or money (having a professional do it), a too-thick profile can be improved. If the job entails removing a significant amount of steel, it is best left to professionals. At this time, such an ax can be sent to Bark River Knives (6911 County Road 426, Escanaba, MI 49829), who’ll gladly do the work (though the wait may be long as the company doesn’t tackle custom work until orders have been met). The bit can also be properly convexed at the same time.

Craftsmanship ~

Most anyone can recognize inferior craftsmanship in an ax. The fit of the handle to the eye is poor with gaps showing, the head is crudely finished, the grind uneven, the edge dull and the handle is uncomfortable and/or poorly designed. Most makers of low-quality axes often paint the head and handle to hide defects. High quality axes may occasionally feature a painted head but always include a clear finished or stained handle so that the grain may be easily seen. With a good ax, the grind is good, the edge sharp. The head is nicely finished. The handles are correctly shaped and well balanced. Still, while fit and finish are important clues to how good an ax is, the highest grade of finishing makes little difference if the handle alignment of the ax is imperfect.

If you were to hold the head of the ax with the edge up and the handle away from you and sight down the length of the handle to its end, the eye, edge and handle should be in perfect alignment. If the alignment is off, the ax will be inaccurate. Typically, an ax is misaligned due to a malformed eye; a defect in forging that cannot be fixed. Sadly, many more misaligned axes pass inspection today than in the past, and you may have to search to find one with good alignment. While even the best brands of axes may be found to have an off-center eye, it is thankfully uncommon. The only advantage to a misaligned ax is if the user consistently strikes the log on one side or the other of their intended target. If they do, then using an ax with a handle that is off-center can improve their accuracy provided the handle is misaligned on the correct side of the head.

The “Hang” of an Ax ~

The hang refers to the tilt (if any) of the ax head up or down in relation to the handle.  After checking the alignment, place the ax on a table with both the cutting edge and end of handle touching the tabletop.  If the hang is good the cutting edge will touch the table at a point one third from the bottom of the cutting edge (the heel).

Correct Ax Hang, from Woodsmanship (1954), The Barnes Sports Library, A.S. Barnes and Co., New York, NY.

The Handle ~

A fine ax should be fitted with a proper handle. One that’s comfortable and suits you. When I say proper, I refer to the material, the shape, the graining and the finish of the handle.

Material ~ It has become increasingly common for manufacturers to offer axes with handles of fiberglass or another synthetic material. Such handles are maintenance free and very durable. They lend a high-tech appearance to an otherwise ancient tool. However, just as no classic English roadster should be painted metal flake purple or vintage bamboo fly rod paired with an automatic reel, no fine ax should be hung with anything but a proper hardwood handle. Hardwood offers the best combination of strength, shock absorption, and grip comfort. With synthetic materials, you have no choice but to live with the handle the ax came with. It cannot be altered. Not thinned in diameter or otherwise shaped, or even be swapped, as nearly all are permanently mounted. A wood handle can be subtly or significantly modified if need be. In addition, if you desire a longer handle or different handle (straight or curved) on a particular ax, there are many different types of hardwood handles available to choose from. Not so with fiberglass.

Wood ax handles are most often made from American Hickory, the favored species used for striking tools. Other woods such as ash, maple and bois d’ arc are also used, but hickory is best. When a cut hickory log is viewed on end, the center of the log contains a dark, reddish wood known as the heartwood. Between the heartwood and the outer bark, a narrow band of light, cream-colored sapwood is found. This makes up a very small portion of the tree. More heartwood is available to the handle maker than the sapwood and this makes it less expensive by comparison. Many sources state that the clear sapwood is stronger and more shock resistant but numerous tests have shown that no difference exists in strength or shock resistance between the two types. Sapwood, heartwood or a mix of the two are all acceptable in an ax handle.

Shape ~ Ax handles are made curved and straight. Of course, a double-bit ax handle must be straight for both bits to be used. While single-bit axes with curved handles are only seen today, straight handles were the norm up through the mid-nineteenth century. Although the curved handle appears graceful, it’s less accurate and more likely to break. Accuracy suffers because the gentle 10° curve at the end of the handle, acts to effectively extend the bit 4 ½” forward of where it should be. As the bit of a straight-handled ax should ideally lie 4 ½” from the axis of lateral pivot of the ax (this is known as the foresection), an added 4 ½” works to extend the foresection to 9”. The further the bit is from the axis, the less accuracy. This doubling of the foresection increases deviation by double over that of a straight handled ax (meaning that an ax with a curved bit is twice as inaccurate as one with a straight handle). And that’s assuming no more than a 5° movement of the wrist when chopping. More than that and deviation increases exponentially. A curved handle is more likely to break because the grain does not run entirely straight from end to end but instead, cuts through the bend of the handle. To offset this inherent weakness, curved handles are generally made thicker than straight handles with the result being reduced flexibility and increased transmission of shock to the user. Still, the benefits of a straight handle would only be recognized in the hands of a professional. Outdoor recreation users will not wield an ax enough for the difference to matter.

Grain Orientation ~ All wood-handled striking tools should have as good grain orientation (usually described as being straight grained) as you can find, in order to be as strong as possible. This means that the grain runs parallel to the eye of the head. If the grain runs side-to-side, then using the ax contributes to fatigue and ultimately results in handle breakage. Of course, it would be expensive and wasteful to ensure that every handle was perfectly aligned and no manufacturer intends to use handles with a perpendicular grain, so you’ll find most handles with the grain being around 25° off parallel though it’s not uncommon to see some far worse. I’ve heard it said that a dozen axes might have to be inspected before finding one with good grain orientation. That’s an understatement. In reality, unless you happen to live in timber country, with access to a large forestry supply that stocks enough axes to provide a large selection, finding an ax with a straight-grained handle can be very difficult. While you can find many ax models online, you’ll rarely find someone willing to comb through their stock to find a straight grained example. Considering the difficulty in finding an ax with decent grain orientation, its best to pick the best example you can find and if you happen upon a handle with perfect grain orientation, BUY IT!

Ax Graining – What to look for

Oiled Finish ~ The wood handles of any striking tool should have an oiled finish. Varnished, lacquered or polyurethane coated handles create a smooth, impenetrable surface that causes blisters.  An ax handle with a penetrating oil finish allows you to grasp the wood itself, resulting in a more comfortable and secure grip.  Some manufacturers offer wax finished handles, which are far superior to a varnished or lacquered helve and which I rate a slight second to oil.  Of course, if you are considering an ax that meets all of the other criteria but for having a varnished or lacquered handle, that can be remedied by sanding off the finish and oiling the handle yourself.  The most recommended oil for tool handles is raw linseed (food grade flaxseed) oil.

Now you’ve been armed with all the knowledge you need to select an great camp ax or hatchet.   In my next post I’ll discuss some of the ax types most appropriate for camping.  Hope this helps!