Daniel Jackson

Making Knives the Old-Old-Fashioned Way

Many knifemakers use today’s best stainless steel money can buy. Other, more do-it-yourself types may scrounge a scrap yard for car springs or ball bearings. Still others go further because all that metal came from somewhere. What if a knifemaker went back to the beginning—starting with the iron pulled from the ground?

In recent years, some smiths have started from square one, pulling raw material from their surroundings to create metal from scratch—just like mankind did for thousands of years. Since the beginning of the Iron Age circa 1200 B.C., man has turned to the iron found in bogs. There, thanks to springs and bacteria, the iron forms into a spongy iron-bearing hydroxide mineral called a goethite.

This renewable source of iron was so important that even the first iron works in America, Saugus Iron Works in Massachusetts, gathered its raw material from nearby bogs. But to turn bog iron into a knife? It’s not a project for the faint of heart.

“You have to prepare hundreds of pounds of charcoal; find, harvest and prepare the ore, build the smelter and then monitor and feed the fire for hours just to produce the bloom,” ABS master smith Kevin Cashen notes. “Then the real heavy work begins of forging it down into a piece of steel that is historically interesting but nowhere near the quality product you get from your modern steel supplier.”

And then there’s the problem of smiths not knowing exactly how the ancients smelted iron.

Darrell Markewitz is a Canadian artisanal blacksmith and historical interpreter of the Vikings who settled in Vineland. He says he is “concentrating on rediscovering lost historic smelting methods.”

For example, he had to make intelligent guesses as to how Vikings tracked time during the smelting process, and how the ancients designed bellows because no bellows from that time exists today.

Sourcing Bog Iron For Making Knives

Relatively speaking, Jarkko Niskanen had it easy when he harvested iron out of a bog in Finland. From a boat, the 26-year-old blacksmith simply felt along the bottom of a bog for spongy chunks of material. Markewitz found himself kneeling over a rivulet running through a Canadian bog, feeling for deposits of iron.

Cashen indicates his home state of Michigan is filled with iron. However, only a small portion is bog iron, small chunks of concentrated iron deposited by bacteria on the slow-moving side of streams running through the bog.

“I have found entire cliff faces in the wilds of Michigan’s Upper Peninsula that a magnet will stick to, and huge sections of magnetic black sands on the shores of Lake Superior,” he observes. “But bog iron requires special conditions. I have found some scant deposits locally but not enough to work with regularly.”

There are different kinds of bog iron. All require the same kind of process to turn out a metal. Some types of bog iron react slightly different than others in the smelter, reducing to a smaller amount of usable material, for example. The end result is the same, however: a lump of relatively pure iron.

Once the smith harvested the bog iron, then he cleaned and dried it. Niskanen put his bog iron in a fi re to dry the pieces, and then broke them up until they were small and uniform.

Making Knives Like The Vikings

The process all happens in the bloomery furnace, in what looks like a chimney with an air pipe going into the side to pump in oxygen. It’s a design going back at least as far as Viking times.

“In operating a ‘short-shaft ,’ direct process bloomery furnace, higher air volumes have proven to produce larger, more dense iron blooms—in fact, blooms most like those few found in the archaeology,” Markewitz states.

As the temperatures rise and charcoal continues to be shoveled in, a chemical reaction takes place inside the furnace.

“The ore is always an oxide,” Markewitz continues. “The smelting furnace is a reduction process removing the oxygen from the ore.”

Charcoal produces carbon monoxide, which reacts with the oxidized iron. As oxygen leaves, the iron particles are left behind and fall to the bottom of the furnace. At the interior temperatures, typically something around 2012-2192°F or more, the heavier iron particles are slightly “sticky” and sinter together has they fall, Markewitz adds.

However, bog iron is also filled with non-iron materials, such as ash and sand. In the furnace, the latter liquefy and fall to the bottom of the furnace where they create a greenish-black glass, or slag, in the shape of a bowl.

“The top surface of this bowl is closer to the hot area of the furnace [at the blast level and] so remains a liquid,” Markewitz explains. “If too much of this slag is produced, its interior level can rise up to block the air blast. Before this happens, ideally you want to let some slag run out [by tapping the furnace].”

If all goes well after hours of running the furnace, a ball of iron that is fragmented and filled with pockets of slag, but iron nonetheless, will result in the bottom of the smelter. However, what if the metal workers make the furnace too hot? Then, instead of iron, cast iron may be the result—unusable for forging.

“If the iron particles are made too hot, they liquefy. As a liquid, iron will frantically absorb carbon—so fast, in fact, that the iron almost certainly shifts into a too high-carbon cast iron,” Markewitz states. “This material cannot be forged, and is so hot it usually melts through the bottom slag bowl and collects at the ground level of the furnace … The real truth is that it takes skill and experience not to get high carbon cast iron.”

Most smelts are a community effort. Cashen says his most satisfying smelt was in 2009, one he dubbed “The Matherton Forge Iron Age Challenge.” The goal was to smelt and forge an iron sword in three days as a public demonstration. When Markewitz reenacts Viking smelts, he does it with a team of three other people.

Niskanen took photos of the smelts, which he published online. For ancient metal workers, team effort was out of necessity. After all, bellows are hard to operate for hours at a time to feed a hungry furnace. To keep time, Markewitz’s team chanted, sang songs and focused on heartbeats—possibly historical timekeepers.

“The effective pumping rate was one stroke per second, alternating between the two chambers. Individuals varied on their stroke force [delivery pressure], but averaged 60-to-75 strokes per minute. This was without interruption over the course of the entire firing sequence extending roughly five hours,” he stresses. “We found that to maintain the needed consistency, we needed four individuals working in roughly 10-minute shifts. This labor force needed to be at least semiskilled to the task. This is a requirement totally separate to the needs of feeding and operating the furnace itself.”

Every few minutes, another person would shovel more charcoal into the furnace. Niskanen said he also added crushed limestone to his furnace to enhance the smelting process.

Making Bog Knives

The metal worker is not done once the iron is pulled from the furnace.

“To actually form a solid working bar, the sponge needs to be compressed at welding heat to collapse the voids, squeeze out any glass slag and fuse to a solid block,” Markewitz explains.

While every bloom is different, the smith needs to fold, weld and hammer the metal until it’s a unified—and, hopefully, homogeneous—metal bar.

“And every bloom is a bit different in terms of just how solid it might be at the start, how much slag needs to be ejected, and in what the actual starting carbon content might be,” Markewitz notes.

Then, finally, the bladesmith can practice his craft. For Niskanen, it was only natural to use the iron for a traditional knife. He made a puukko, an ancient Finnish knife (pictured at top of this article).

“Since the Iron Age, the knife has been used as a multifunctional tool in everyday life,” he opines. “And for a hunter it is, and always has been, one of those items you can’t go without into the wilderness.”

Niskanen was there from the beginning, when the knife was only a lump of iron oxide resting on the bottom of a Finnish bog, “It makes the blade really personal,” he says.
Markewitz used his iron as a decorative part of the knife.

“For the modern designs, I use the bloom iron specifically to highlight its unique texture,” he observes. “Blades like [my Hector’s Bane model] have bloom-iron exterior slabs forge welded to a carbon steel core. As with other inset-styled blades, it is this modern alloy core that is forming the actual cutting edge.”

He did it that way because iron blades don’t perform as well as blades of modern steel.
During the Iron Age, Markewitz says iron knives were so soft that users carried a small sharpening stone with them because they had to constantly hone the edges. Nonetheless, some knives no doubt performed better than others.

In a 2013 study published in The World of Iron London, archaeo-metallurgists Quanyu Wang and Peter Crew compared the performance between three knives made from bog iron. Their paper, titled “Three ores, three irons and three knives,” found that the performance of the knives probably was determined by the skill of the smith and the trace elements in the blade, such as phosphorus, which is known for making iron stronger and harder in trace amounts.

However, phosphorous also can make the metal brittle in cold weather. They compared three bog-iron knives by examining the microstructure of the blades and using the knives to butcher a pig.

Wang and Crew concluded their study by writing, “The quality of bloomer iron depends very much on the smelting and refining techniques used, which may not always be recognizable from the structure and composition of the final metal.”

These smiths have more furnaces to build, iron to smelt and possibly blades to make.

“I have studied older bloomery steel, as well as modern smelted materials under the microscope, and tested the properties, and am quite impressed with the smelting skills of the ancients,” Cashen concludes. “Modern academics had only their best guesses about this process until people started actually doing it again, and then we learned how little we actually knew. We are fumbling our way through a process that our ancestors had completely mastered, developed to its highest levels and then discarded in favor of newer and better processes of making steel.”

As noted in Monty Python and the Holy Grail, “strange women lying in ponds distributing swords is no basis for a system of government.” On the other hand, oaken logs lounging in bogs for a couple of millennia transform into something of a “holy grail” for knifemakers.

The oxygen-poor, acid-rich bog environment changes humble woods such as oak into something dark and infused with history. And it’s in no small part because of this that makers have turned to the material for knife handles.

Knives seem to have a long relationship with bog oak, a prized and precious wood pulled from bogs after thousands of years.

For instance, take the Scottish sgian dubh, the small utility fixed blade sheathed in the sock of a Highlander in traditional Scottish garb. Translated from Gaelic, sgian dubh means black knife, which some think is a reference to the dark bog oak from which the handles of a number of sgian dubhs were carved.

Just as oxygen-poor and acid-rich bogs transform wood, some makers have gone beyond traditional sgian dubhs and use the handle material to hearken back to more mysterious and historic times.

Black Betty

Because it takes ages to form, bog oak is a finite resource. ABS journeyman smith Mike Deibert, who makes knives on the weekends and evenings when he’s not working as an elementary school teacher, waited five years after he bought a piece of bog oak for the right knife to come along.

The large, handle-sized piece of the material came already stabilized. Deibert has most of his natural handle materials stabilized so they’re not subject to fluctuation in humidity and are more predictable to work. Even before he decided to use the bog oak, the project was going to be a special one.

“The Black Betty Bowie was created in September of 2019,” Deibert explained. “I designed it for a client who wanted to present it as a gift to an individual who was responsible for raising hundreds of thousands of dollars for cancer research. I wanted to come up with a special work of art that even a non-knife enthusiast couldn’t help but appreciate.”

Deibert started with a bold-featherpattern-damascus design by working out the pattern on paper. When he saw the finished billet, the contrast thrilled him. Besides its tight grain and chocolate color, the wood, billed as a 5,400-year-old relic pulled from a bog in Ukraine, gave the blade historical gravitas.

“When I saw how incredible the dark plume billowed down the center of the blade, I knew I had to put together a guard and handle that complemented this intense feature,” he began. “Originally, I had drawn the knife with a piece of ironwood burl in mind for the handle and a satin-finished steel guard. But, with a very dark portion over most of the blade, I decided to go with all-dark furnishing as a complement.

“This wood, once growing and living thousands of years ago, is now preserved and on display as a handle on the world’s oldest tool. There’s a story in it, and it makes me proud to be able to keep that story going.”

Baba Yaga

What kind of knife would Baba Yaga, a mysterious and terrifying old woman in Slavic folklore, wield as a war blade? That’s the question Connecticut knifemaker Matt Berry pondered as he read through Katabasis, a novel in which the wicked witch swoops in for an appearance.

“Babayaga’s Warknife” began with a blade Berry had put aside after beginning it in 2016.

“I started with the pommel carving, which was meant to be Baba Yaga’s face. The rest of the handle just kind of fell into place as I worked forward from the pommel,” he recalled. “I worked on it as time and inspiration allowed and finished it in the spring of 2019.”

One of the highlights of the knife is the pommel. Berry carved the bog oak to fit into the bronze pommel and ferrule, which he created by casting them via the lost-wax method. The oak for Berry’s handle entered a bog about 5,300 years ago and helped set the knife’s tone.

“I wanted something European even if bog oak was never used in the 1200s,” Berry said. “Bog oak is quite expensive. It’s right up there with burl in price and will sometimes cost more. There’s not a lot of it around and the supply is finite. I get most of mine from an English furniture company that digs up and dries its own logs and then makes high-end furniture. I’m buying the company’s scraps.”

Like anything that has sat around for a few millennia, bog wood has its quirks. According to Berry, it can be as temperamental as Baba Yaga herself.

“The grain isn’t tight, and it’s kind of mushy and chippy at the same time,” he warned. “Th at makes it very frustrating to carve. It drills and sands fairly normally but it can be prone to splitting.”

Dagger of Firsts

Brant Cochran of Gray Flame Forge works in the insurance industry but, when he can, he’s in his shop. When he created his 10.5-inch dagger with a blade of W2 tool steel and a bog oak handle, it was a project of firsts.

He took three months to slowly build the dagger, in part because it was his first time making a dagger of that length. While he wanted to make a large knife, the quintessential bowie didn’t appeal to a man whose interests in edged tools were whetted when, as a youngster, he saw an arming sword at his grandparents’ house.

The dagger was the first time he had made a knife with a cross guard, a pommel, takedown construction and a bog oak handle. He initially had planned on making the handle from ironwood. Then, after some African blackwood got “screwed up,” Cochran turned to a piece of bog oak.

“I’d never used it before,” he stated. “I was already doing all these new things—why not try a new material as well? That was part of it. But I was interested in bog wood because it has a historical element to it. It had spent 3,300-plus years sitting in a bog.”

His impressions? The bog oak worked a heck of a lot better than ironwood.

Furthermore, it was almost the perfect carving wood. He created a subtle ridge running down the length of the handle. The wood wasn’t soft enough for the subtle feature to get “completely washed out,” nor was it hard enough that it required extra effort to eliminate the sharp edges. The dagger of “firsts” became a springboard to future projects.

“I would work really hard on one piece as I was trying to build up my skills,” Cochran said. “Then I would bring it to master smiths I knew and respected to get it critiqued. A picture is not going to show you every little detail you need to figure out how to make a quality knife.

“Your edge might have good retention but if your handle’s too thick or just very uncomfortable, you might not pick that up. And, by speaking to the master smiths and having them show you what those details are, you can then train your own eye to do it as you move forward.”

Perfect Complement

For Anders Högström, bog oak is a relic from an ancient time and a perfect complement for his Valdez ceremonial dagger.

A full-time knifemaker who lives in southern Sweden, Högström is also a hobby chef when he’s not crafting knives. One vein of his work is to build knives of cultures that are combined or are long-ancient ones that persisted for years.

According to Högström, “My main direction of design is that of a marriage between the Nordic and Japanese.”

He uses a lot of one-off casting and hamons. For his short-bladed ceremonial knife, he went with a model he imagined could have been used by an ancient American Indian culture, such as the Inca or Maya.

“The ceremonials I make are a sort of homage to what would have been used by a high priest, shaman or someone of similar standing at a ceremony of importance,” he explained.

Högström indicated bog oak pairs well with other materials. For the Valdez, he “married” the 1,200-year-old material with ancient walrus ivory left raw in the handle butt to provide texture. The bog oak, he said, carried a “meaningful weight”—almost as if the material were an artifact of an older time.

“Something ancient that has been left to decay—but, as nature would have it, something happened in the process, and the original material got to evolve into something else—much like the fossil walrus ivory in the handle that was colored by minerals in the ground and because of the thousands of years it stayed there,” he mused.

Högström pointed out that some pieces of bog oak must be stabilized because they might be soft and the pores of the wood must be filled.

It depends on the project. However, for his ceremonial dagger, he said the unstabilized wood was “easy to work and medium soft.” He chose a fine-steel-wool finish to get into the wood’s grain, thus bringing out the most character. This was followed by a couple of coats of wax to protect the surface.

When customers learn of the bog oak’s history and the stories it evokes, Högström said they often react with “both amazement and amusement, as well as a certain reverence.”