We break down what common steel alloying elements add to a knife.
Alloy… in the knife world we hear the word often. Blade aficionados—many almost journeyman metallurgists in their own rights—pour over steel composition. Newbies to collecting and making, however, might be a bit perplexed over exactly what the material modification is all about.
With this in mind, we’ve boiled down what certain elements—when alloyed with iron—bring to the table for your knife. Now this isn’t a deep dive into the nitty-gritty of what each element does in a steel alloy, complete with phase diagrams and quenching charts. Honestly, if you need to cut to this quick, we recommend Larrin Thomas’ website KnifeSteelNerd.com. The son of BLADE Cutlery Hall of Fame member Devin Thomas and PhD metallurgist and material scientist, Thomas offers a much more in-depth look at steel from an engineer and knifemaker’s point of view.
What we have here is a quick and dirty guide to alloy elements and what they bring to a knife.
What An Alloy Is
If your high school chemistry class is a bit foggy right now, perhaps we should take a moment to do a quick review of exactly what constitutes an alloy. Quite simply, an alloy is a mixture of two or more elements, where at least one of the elements is a metal. Note alloys are mixtures, not compounds—the former is a physical combination, the latter a chemical. For a mixture, think of something like oil emulsified in vinegar to create a tasty salad topping, while a compound is two gases like hydrogen and water bonding together to form water.
Alloying elements is done to enhance the properties of a material. In the case of knife steel elements are combined to improve toughness, wear resistance, corrosion resistance or other factors. While we won’t delve that deep in this article, we’ll point alloys can be classified into two main types:
Substitutional Alloys: In these alloys, the atoms of one element replace or substitute for the atoms of another in the metal lattice. An example is brass, which is an alloy of copper and zinc.
Interstitial Alloys: In these alloys, smaller atoms fit into the spaces (interstices) between the larger metal atoms in the lattice. Steel, which is an alloy of iron and carbon, is an example of an interstitial alloy.
Since we’ve dusted off some of those long-lost materials lessons you learned, let’s get into the down-and-dirty of what each common alloying element brings to knife steel.
Knife Steel Alloy Elements
Carbon: This ingredient makes the difference between iron and steel; all steel will have some amount of carbon. It is the most important hardening element, but it makes hardness by combining with other elements. As a simple generalization, the amount of carbon in the steel tells you a lot about the quality of the steel. Low-carbon steel has 0.3% carbon or less, medium has between 0.4-0.7% and high-carbon steel is 0.8% and above, maxing out at around 1.2% carbon for knife steels. Up to a point, the higher the carbon content within the range, the harder the steel will get.
Chromium: Chromium combines with carbon to make chromium carbides, which are resistant to corrosion. Stainless steel knives will have chromium as a major ingredient, typically at a minimum of 12-13%. Chromium also increases the strength of a knife to a degree, but adding chromium in large amounts decreases toughness.
Cobalt: In small amounts, cobalt increases toughness.
Manganese: This changes the rate of hardening. Manganese in carbon steels yields “deeper” hardening, which requires a slower speed quench and gives a wider range of acceptable heat before quench. If added in high quantities, it can increase brittleness. Manganese makes steel etch dark in damascus.
Molybdenum: Adding this maintains the steel’s strength at high temperatures.
Nickel: Nickel adds toughness to steel. It also makes steel etch bright in damascus.
Nitrogen: This element is sometimes used as a substitute for carbon in steel.
Silicon: Silicon increases strength and removes oxygen from the metal while it is being formed. It’s typically present in small quantities in most steels.
Sulfur: This increases machinability but decreases toughness.
Tungsten: Adding this increases wear resistance and forms tungsten carbides that are very hard.
Vanadium: Vanadium leads to smaller grains within the steel. Vanadium carbides are very small and hard, which increases wear resistance and edge retention.
Bladesmiths outline which carbon steel combos they use and why.
Damascus steel is a broad category with nearly infinite variations. It includes everything from low-layer random patterns to powdered canister creations and complex mosaic patterns.
The basics of damascus include forge-welded combinations of steels. Changes in the steel choices, in the welding or forging processes, and even in the etching method result in a wide variety of patterns and looks. Let’s dive into the many levels of damascus through the work of a few excellent smiths.
Smiths Takes On Damascus Steels
ABS apprentice smith Chris McPherson began making knives only four years ago, but he had a strong start attending classes taught by ABS master smiths Jason Knight and Josh Fisher. Now he forges his own damascus. One of his fighters (IMAGE 1) features a blade of 1075 carbon and 15N20 nickel-alloy steels.
Image 2 ABS journeyman smith Brian Sellers used three steels instead of the standard two to help provide a darker look for his blade of ladder pattern damascus. As he observed, “Adding a third steel to damascus gives a unique depth to the finished blade, kind of like adding shades of gray to a tattoo.” (Jocelyn Frasier image)
“I made the knife for a local state trooper benefit, for the teenage son of an officer who lost his life in the line of duty in March 2023,” Chris explained. When asked about why he chose 1075 for his fighter, he said he “just wanted to try it out” after making other billets with 1095, 1084 and 1080 carbon steels. Though he’d heard that the 1075 may have a bit less contrast due to its lower manganese levels, it came out with beautiful contrast after a deeper etch.
Knifemaker Brian Sellers likes to mix things up a bit. In addition to the standard carbon steels of 1095 or 1084, Sellers occasionally includes 1080, 5160 or 52100. “Adding a third steel to damascus gives a unique depth to the finished blade, kind of like adding shades of gray to a tattoo,” he says. For example, in a recent Persian fighter (IMAGE 2), Sellers included 1080 and 5160 along with 15N20 in a ladder pattern blade. Brian indicated all the steels work well with his equipment. He uses a 50-ton Riverside hydraulic press and a 50-pound Little Giant power hammer.
Damascus is time and labor intensive, and the maker loses a good bit of the steel in the forging process. Bladesmith Blake Nichols knows this and is from the “waste not, want not” school of thought.
Robert Wayman uses a hydraulic press to weld and draw out his damascus billet.
“My mentor Greg Shahan gave me the end cut of a feather damascus billet a few years ago,” Nichols said. “It sat on my shelf for a long time before I incorporated it into [one of my] hunters.”
Regarding his damascus, he added, “I wish I had a profound scientific answer as to why I use 15N20 and 1095 but I do not. The simple answer is it’s what I learned on. I’m comfortable with the heat-treating process. I also feel like I get the performance out of that combination that I desire.” I agree with Nichols when he said, “No matter what it’s made of, it has to function like a knife. Even the fancy ones need to hold up to the performance standards.”
Why 15N20 In Damascus?
Image 3 For a great example of a go-mai (five layer) damascus blade with the visual “pop” of nickel, Robert Wayman provides the fireworks via his sujihiki. Damascus outer layers and a damascus core work together with the handle of live edge amboyna burl to make a stunning knife. Overall length: 16 inches. (SharpByCoop image)
You may have noticed one thing the featured bladesmiths all have in common: they include 15N20 in their damascus billets. The 15N20 is a simple carbon steel, basically 1075, but has a relatively large amount of a special ingredient: nickel. The nickel content makes 15N20 etch more slowly and show more brightly when polished. Because of the similar composition to the 10-series steels (1080, 1084, etc.), it welds well and hardens in similar temperatures, making it the perfect steel for high contrast in the damascus pattern.
Some smiths use pure nickel foil or sheet in their damascus for the same effect. The challenge is that the pure nickel won’t harden, so it must be kept away from the edge in the forging process. The contrast is great but the nickel itself won’t hold an edge. I like a nickel layer in between layers of san-mai or go-mai damascus. It really pops!
Bladesmith Robert Wayman illustrates the go-mai technique well on one of his kitchen knives (IMAGE 3). The blade was made from a patterned go-mai billet. There’s a core layer running down the center of the blade with two layers of material on each side. The core is 100-layer random pattern damascus forged from 1084 and 15N20. On each side of the core steel is a layer of nickel and on the outside of the billet is a layer of matching random pattern damascus.
Key Element Comparisons by Steel
Steel
1084
1075
1095
15N20
1080
5160
52100
C
.865
.750
1.000
.750
.75-.88
.60
.98-1.10
Mn
.750
.550
.450
.375
.06-.09
.80
.24-.45
N
—
—
.200
1.950
—
—
—
*C-carbon, Mn-manganese, N-nickel; the double hyphens indicate trace amounts. Note the relatively high amounts of nickel of the 15N20 and of manganese of the 1084, two elements beneficial for high contrast damascus. This chart is for the elements pertinent to the subject at hand only and does not list all the elements of each steel.
Once the final billet is forge welded, some of the cladding material is removed with a grinder to create a visual effect in the pattern, and then the billet is drawn out to length. Keeping the core material centered during the process is very important. “You want to take your time when laying out your billet,” Wayman advised. “I typically use a thicker core material and a thinner cladding material, but it’s definitely taken some time and practice to dial it in.”
Other Damascus Steels
Before 15N20 and 10-series combos became prevalent for damascus, one of the standard high-contrast combinations was O1 and L6 tool steels. While the latter combo makes great damascus, the two steels are harder to find in today’s market. Simply put, properly sized and affordable 15N20 and 10-series steels are much more available than all the other combos on the market.
Damascus can be made of many things, including other damascus. These component bars became part of Robert Wayman’s chef’s knife.
Copper is another material that has caught on in the forging of copper-mai and other forms of copper damascus. Outfits like Baker Forge specialize in the process in which the copper is often clad over a standard carbon steel damascus core, as the copper itself won’t harden.
Titanium alloys have been pattern welded, often called Timascus™, and can be anodized in an array of wild colors. Unfortunately, it’s difficult to produce and doesn’t harden, so Timascus blades are probably not in your future. Instead, Timascus makes a great folder frame, bolsters and other non-blade knife parts.
What Metals To Avoid
Are there any materials that don’t make a great contrasting damascus? Sellers reports that the “S” series high silicon steels like S5 and S7 don’t work. He speculated that it was either the steel composition or improper heat control, but welds of S5 and S7 don’t stick during forging.
Robert Wayman welded these five pieces of steel together to make the go-mai damascus blade of his chef’s knife.
I can attest that meteorite is a tempting addition to damascus because various samples are often high in nickel and mostly made of iron. Unfortunately, every meteorite varies widely in terms of content, so that individual pieces of the same meteorite each may have a very different chemical composition. As another confounding factor, many meteorites contain high silicon or other elements besides iron, carbon and nickel. Each new element adds its own problems to the process.
I was able to produce a satisfactory pair of billets containing some meteorite by putting small chunks in a canister with 1084 powder, and then welding and re-stacking the billet with more 1084 bar stock until the final layer count was over 1,000. By adding only 1084, I was assured that any bright spots in the final pattern were from the nickel in the meteorite. Even with this process, there were a few inclusions/flaws in the final product. Could I have continued to push the layer count and minimized the flaws further? We’ll never know.
Some may think AEBL stainless steel is nice and shiny. Can it or another stainless steel be put in the mix with carbon steel? If you think that “shiny” makes sense for high contrast, that part is true. Unfortunately, the high chromium in stainless steels causes problems for damascus makers in two ways. First, chromium steels don’t like to weld together. The chromium oxidizes quickly and prevents the welds from sticking. Second, the chromium changes the hardening properties. In a hypothetical AEBL and 1084 billet, the AEBL hardens from 1,900°F while the 1084 hardens from 1,500°F. If you quench the hypothetical billet from 1,900°F, the 1084 will have huge, brittle grain. If you quench the same billet from 1,500°F, the AEBL won’t harden.
For the blade of his fancy hunter, Blake Nichols employs a damascus of 1095 carbon and 15N20 nickel alloy steels forged by Greg Shahan. Blake said he is comfortable with the heat-treating process and also feels like he gets the performance he wants from the combination of the two component steels. Overall length: 10 inches. The scrimshaw is by Charles W. Conner III. (SharpByCoop image)
While there are smiths who have figured out how to weld multiple types of stainless steel together in contrasting patterns, the process requires careful and precise heating and mitigation of oxygen, both procedures which are often beyond the scope of the backyard smith. Because of the complex process required to make it, stainless damascus commands premium prices.
Final Cut
Modern damascus retains strong demand in the knife market. By combining a choice of several standard carbon steels and 15N20, smiths can create damascus patterns that will make any knife stand out. Whether the pattern is random or ladder, raindrop or mosaic and more, a high-quality damascus knife is sure to be a winner.
Some lean traditional, others modern and others “whatever’s in my pocket is fine”.
There are times when a pocketknife is essential and times when it’s not pragmatic. Though I’m guessing most BLADE readers wouldn’t be the ones who’d cause a problem, have you ever had a knife confiscated by the Transportation Security Administration? Sure, it’s in the name of world peace or whatever, but if you find yourself frequently in airports the best pocketknife might be the one you leave at home.
I’m fixing to admit a heresy: As a knife writer and knifemaker with a work-from-home day job, I don’t often carry a pocketknife. I have a small imported Benchmade on my work desk, and some of my “knife collection” is in my office, but that’s all. In my house I’ve got knives everywhere I go—kitchen, bedroom, office, outdoor shop, all over the place. I rarely carry one yet rarely go without. I also fly occasionally, so even my keychain knife has become out-of-pocket.
Let’s drill down through all the “it depends” and get to the final question: What’s the perfect pocketknife? Of course, there’s no definitive answer but there are some perspectives.
Jordan Wagner of DLT Trading
The Les George VECM is clean and ergonomic and checks the boxes for a high-end modern pocketknife: premium CPM MagnaCut stainless blade steel, titanium framelock and easy opening.
When it comes to the modern high-end folder, Jordan Wagner of DLT Trading said, “My favorite would be the Les George VECP. What sets it apart for me is Les’s tremendous attention to detail in both design and execution. His designs are clean and simple without being pedestrian, and they perform phenomenally in use. The VECP handle has fantastic ergonomics and is comfortable in multiple hand positions, while still feeling safe and locked in during use. The blade shape is functional and handsome, and his grinds tend to be extremely slicey. The VECP really hits all the buttons I look for in an EDC knife.”
Ben Petersen of Knafs
According to the author, the CIVIVI Sendy designed by Ben Peterson combines some of the best elements of traditional and modern design, including a barlow-shaped frame, choice of a clip-point (shown here) or spey pattern blade, Nitro-V stainless blade steel, a Micarta® handle, flipper tab, linerlock and the author’s favorite: a tweezers and toothpick that slides under the scales a la a Swiss Army knife.
In addition to being co-founder of Knafs, Ben Petersen also designs knives. His latest entry is a model produced under the CIVIVI brand called the Sendy. In an innovative genius kind of way, Ben combines some of the best elements of traditional and modern design. The knife comes in Nitro-V, a stainless steel that threads the fine line between ease of sharpening and edge holding. It compares favorably to the traditional carbon steel knives of old yet sharpens much easier than the newer powder-metallurgy super steels.
The Sendy’s overall profile resembles a traditional barlow, with straight lines and a butt end wider than the tip. The blade comes in both spey and clip-point patterns. Also thrown in are more contemporary features such as a front flipper tab, linerlock, ceramic bearings, and a deep-carry, reversible pocket clip. However, what really sends this one over the top for me is the inclusion of tweezers and a toothpick that slide under the scales in the traditional Swiss Army knife configuration. Ben successfully combined modern and traditional elements into a very versatile, user-friendly pocketknife.
Goldie Russell Of A.G. Russell
A pocketknife that appeals to the author is the Skinny Brute from A.G. Russell Knives, a traditional lockback in CPM S35VN stainless blade steel. There’s a choice of carbon fiber (2.6 ounces and $135 MSRP) or green G-10 (2.9 ounces and $99 MSRP) for the “skinny”—a half-inch thick at the swell—handle. Blade and closed lengths: 3.25 and 4 1/8 inches. Country of origin: China.
I reached out to BLADE Magazine Cutlery Hall-Of-Fame® member Goldie Russell, who with her late husband, Cutlery Hall-of-Famer A.G. Russell, basically invented mail-order knife catalogs. Over the years the A.G. Russell Knives brand has marketed a huge variety of pocketknives and fixed blades, domestic and imported. The current catalog includes some interesting designs that blend modern and traditional sensibilities. One that appeals to me is the Skinny Brute, a traditional lockback in modern materials.
“A.G. designed the Brute in the 1970s,” Goldie began. “He and handmade knifemaker W.C. ‘Bill’ Davis perfected A.G.’s idea that by using Micarta® a folder could be made without metal liners. The result of that collaboration was the A.G. Russell Brute. At some point in the late 1970s, A.G. stopped offering them. In the early 1990s, we began to work with Bill again and for a number of years they were again made by hand in the U.S.A. For over five decades our customers have loved the profile, the deep nail mark for one-handed opening, the weight and the rest of the features of the design. Now, after many years, it is back, with a handle that is just a little thinner.”
Joe Culpepper of Culpepper & Co.
Joe Culpepper of Culpepper & Co. and Old School Knife Works is a fan of the Case/BLADE Magazine Cutlery Hall-of-Fame® member Tony Bose collaboration swayback jack, as well as other swayback patterns, in either single- or double-blade configurations. (Old School Knife Works image)
When it comes to the traditional pocketknife, Joe Culpepper of Culpepper & Co. handle material supplies and Old School Knife Works is a fan of the Case/Cutlery Hall-of-Famer Tony Bose collaboration swayback jack, as well as other swayback patterns, in either single- or double-blade configurations. “I think the design is simple, clean and elegant, and,” Joe stressed, “jigged bone is a must!”
What’s In Your Pocket?
Even among industry insiders, not everyone has the same preferences or shares the same opinions on what makes a perfect pocketknife. Some lean more traditional, others more modern and others more “whatever’s in my pocket is fine.” No matter your preference, buy all the knives you can afford and carry them as often as you can. After all, you never know—the “perfect” pocketknife may just be the one you have on you when you need it most.
Decades ago in America the pocketknife was universal, with such patterns as the barlow, stockman, trapper and folding hunter well represented in the pockets of our fathers, grandfathers and great-grandfathers. But what about today, when the most likely pocketknife task is opening an Amazon box or trimming a string off a shirt? To find out not only what folks are carrying but why, BLADE® asked several industry insiders, “What makes the perfect pocketknife?”
Pocket Knife Funtionality
Let’s begin our hunt with a look at the past. Many BLADE readers know Joe Culpepper for his and wife Kristi’s knife handle material business, Culpepper & Co. For many years the Culpeppers have provided the knife industry with quality jigged bone, Sambar stag and other exotic materials. Joe is also a student of the slip-joint/traditional pocketknife in all its variations, and sells vintage knives under the business name of Old School Knife Works.
A Case knife in damascus is in the traditional fish knife pattern, an early folding fillet knife. (Old School Knife Works image)
“A good pocketknife first and foremost should perform and function reliably in the way it was designed,” he began. “Whether we’re talking about an electrician’s knife, fish knife, melon tester or trapper, the most important thing is that it does its job.”
The melon tester pattern, here in an advertising knife configuration, almost always has a long, thin single blade. (Old School Knife Works image)
It has been a while since I used a knife to test a melon and Joe, too, was quick to acknowledge that many of the knife tasks of yesteryear have fallen by the wayside. “Frankly,” he admitted, “many of our pocketknives are simply just really nice box cutters.”
Pocket Knife Blade Size
Sticking with the nice box cutter theme, Knafs co-founder Ben Petersen added that he likes knives suited to the “dad life”—cutting apples cleanly without splitting them, opening boxes and whittling the occasional stick. “I’m not out to stab people,” he grinned. “For me, I think a 2.9-inch blade is perfect. Being under 3 inches keeps you safe from most restrictive knife laws, and it also is the perfect length for the finger test.” Ben went on to explain. “Most of the time when I cut, I put my index finger along the spine of the blade,” he noted. “I want the point of the blade right in the middle of my fingertip where it won’t cut me, but also gives me very precise control.”
Medford Knife & Tool offers a range of titanium framelock folders, including the Praetorian T in CPM S35VN stainless blade steel. Weight: 9.3 ounces. Closed length: 4.9 inches. MSRPs start at $785.
Ben had a fun take on the perfect knife. “You know,” he reflected, “to a 12-year-old a gas station knife* is perfect. The perfect knife is totally different to everyone.” I smiled, remembering how much joy my 14-year-old son got from a rusty Bass Pro Shops framelock, missing a screw, that we found in a pasture on a dove hunt.
Types Of Pocketknives
Most of us BLADE readers probably already have a good idea of what we like in a pocketknife. We know if we like small ones or bigger ones for everyday carry. We know the steel types we like, and whether we prefer a single or multi-blade. Joe offered some generalizations that match my experience.
Tradional
Another older Case edition, the hobo knife features a blade and fork in a handy pocket-sized folding knife. (Old School Knife Works image)
“As we get more into knives we tend to evolve into one of two categories, and they’re often correlated with age,” he reasoned. “The older generation tends to go for the more traditional slip joints with natural materials and carbon steel like their dad or grandad carried.”
Joe considers some “classic” patterns and brands among his favorites, particularly the knives manufactured pre-1970 by the old American firms that mostly have gone out of business. “When you hold an old Schrade, Empire, Robeson or even a vintage Case you get a certain sense of nostalgia,” he noted.
Modern
Jordan Wagner said the market is strong for high-quality USA-made titanium framelocks. Among those fitting the niche is the XM-18 3.5 flipper folder from Rick Hinderer Knives. Closed length: 4.75 inches.
As for the other category, Joe finds that younger folks tend to lean toward modern conveniences like pocket clips, modern steels and the more tactical types of knives like Benchmades. Being just a bit on the older side myself, as well as a bit of a traditionalist, I reached out to Jordan Wagner at DLT Trading for some thoughts about what makes a “perfect pocketknife” from a modern point of view.
From an online merchant’s perspective, he said the market is very strong for quality USA-made framelocks. Titanium framelocks from makers like Rick Hinderer Knives, Chris Reeve Knives, Medford Knife & Tool and custom knifemaker Les George in the $400-to-600 price range continue to be popular.
Knives in the modern category tend to have a few common characteristics. They feature premium blade steels. They all have some kind of one-hand-opening device such as a thumb stud, blade hole, flipper tab, etc. In general, these are mid-tech production or small batch customs made in shops as often as in factories. The next level below the mid-techs are the larger-batch manufactured knives by companies like Zero Tolerance, Spyderco and Benchmade. They’re often high quality, built in factories to tight tolerances and most often made in the USA.
Often within these and other brands are quality, lower-price-point knives made overseas as well, such as the production Demko AD 20.5 made in Taiwan. There are also quality knives made by China-based companies like Reate, WE and its sister brand CIVIVI and others.
Case remains the leader in the current production of traditional patterns. But is it because there’s a demand by knife users for a two-blade trapper? Maybe, maybe not. The folks at Case know and understand that there are two big segments of customers that they serve—users and collectors—and they make patterns to please both groups.
The Perfect Pocketknife?
I think about “perfect” in terms of pragmatism. When was the last time the average knife user needed a hobo knife with a fork? Have you ever seen a titanium framelock melon tester? Culpepper has his finger on the vintage-slip-joint market, and his take is that the rise of social media has opened up huge new audiences to the vintage knives.
“The unique patterns always have a market and a strong following,” he said. “For the unique vintage knives there’s good demand, whether they’re made in the USA or even England or Germany.”
A clutch player in the knifemaker’s shop, the tire hammer gives more control than other D.I.Y. power hammers.
Like a variable-speed hand drill, your backyard power hammer should be able to run slowly, at full speed or in between, depending on the task. The simplest way to guarantee it does this is to use a slipping clutch.
There are two main designs of slipping clutch. One uses a slack belt, a flywheel and pulleys. The drive pulley rotates within a slack belt. The foot pedal linkage pushes an idler wheel into the slack belt, increasing the belt tension to the point that the belt begins to turn the pulley on the flywheel.
The author modified the spring-arm-to-pitman attachment to make it adjustable. Depending on which attachment point is used, the leverage of the stroke changes.
Another design uses a tire clutch, where the foot pedal linkage pushes a drive wheel into an automobile tire, with the hub of the tire serving as the flywheel. The most common “tire hammer” design uses a similar clutch but turned the other way and connected to a linkage. Your available parts will dictate your design.
Why A Clutch
A function of the clutch is to reduce the RPM of the motor speed to get the hammer rate of beats per minute (BPM) into a safe and useful range. You want the hammer rate to generally end up between 150 and 250 BPM, though many variables change with each hammer. In general, a heavier tup (aka hammer head assembly) requires a slower BPM, whereas a lighter hammer can have a higher BPM. You do not want your hammer running faster than you can control it, nor so fast that the inherent forces tear it apart. My hammer uses a 24-inch tire and a 3-inch drive wheel for an 8:1 reduction of a 1750 RPM motor, yielding a calculated 218 BPM at full speed. Your hammer will run differently depending on your motor RPM, your drive and driven wheel diameters, and the hammer’s overall design. I rarely run my hammer full speed during general forging work, and the tire clutch gives good speed control. Full speed works acceptably well for drawing out damascus billets or breaking down large stock.
My tire clutch has an integral flywheel bolted to the hub. On the flywheel I welded several different nuts for attaching the pitman arm (for more on the pitman arm, see part three last issue). Each nut is a different distance from the center of the hub. This allows me to vary the length of the stroke, in my case between 6.5, 7 and 7.5 inches, based on where I connect the arm to the flywheel. Coupled with an adjustable-length pitman arm, this setup allows a degree of tuning to get the hammer hitting in a way that transfers the power directly to the workpiece with efficiency, yet in a way that doesn’t place undue stress on the hammer itself.
Choosing A Motor For Your Tire Hammer
As for motors, the size may vary a bit depending on the overall tup weight of your hammer. For most homebuilt hammer sizes, a 1 or 1.5 HP motor is plenty. My 40-pound hammer uses a 1.5 HP motor running on 110v and does not trip a standard 15-amp breaker, suggesting that 1.5 HP is more than plenty for a 40-pound head. Whether the motor runs on 110v or 220v will depend on your shop setup and what you have available, but you’d be best served either way with a motor that runs in the 1700 RPM range, not one that runs in the 3400 RPM range. There’s no need to go three phase or variable speed unless you’re already set up for either.
Doug Davis’ homemade hammer uses a series of pulleys and an idler. When you step on the treadle, the idler tightens the belt and engages the hammer.
You will need an on/off switch for your motor. To run the hammer, turn the motor on, then use the foot pedal linkage to engage the clutch.
Sourcing Dies
Most power hammers have a set of dies in between the anvil and the hammer shaft. Dies may be built in a variety of shapes and sizes, depending on how you want your hammer to move the metal. Two basic die designs are flat and crowned. Flat dies move the metal somewhat equally in all four directions, while crowned dies will draw out the length of your workpiece perpendicular to the crown on the dies. Some smiths design their hammers to accommodate various top or bottom tools, or spring swages as well.
The die attachment on Doug Davis’ power hammer is more robust on the ram-to-die connection, but time will tell how the bottom-die direct-weld works out. (Erik Greiner image)
On my personal hammer, the dies are built out of 1.5-inch square 4140 steel bar stock, heat treated and ground essentially flat, with slightly radiused corners. Some hammers are set up with dies that are interchangeable but mine is not. Full disclosure: My die attachment is one point of weakness in my design. I ultimately welded my bottom die plate straight to the anvil, and I’ve had to reinforce the top die connection and re-weld it several times. Perhaps a more skilled welder could have done better!
Creative Necessity
I can’t emphasize enough the creativity necessary to build a functioning power hammer from scrap. It’s one thing to watch a YouTube video and think, “It must be nice to have a power hammer.” It’s another thing entirely to watch the same video and try to discern how the rocker arm connects to the center post, or how the tire clutch axle is set up.
At the time of my hammer build, there was an online gallery hosted in Czechoslovakia that had hundreds of pictures of various homebuilt and factory built hammers. I couldn’t have built mine without those examples. I don’t speak Czech but the pictures tell the story well.
The Appalachian spring helve hammer, including springs, hammer head/tup and more.
Some people find great joy in precision and following rules and plans. For those of you who do, this is probably not your power hammer series. I enjoy the creativity of making a thing from scratch. It’s not the precision that turns my crank, it’s that eureka moment of, “It works!”
In this installment I’ll talk through the process of building a junkyard hammer in the Appalachian style. Junkyard refers to the DIY-type build made with what you can find. Appalachian refers to a common design that uses a spring helve. The most popular earlier Appalachian hammer designs were called the “Rusty” and the “Dusty.”
Rocker-Arm Springs
I used a set of leaf springs for my rocker arm. The arm is also called a helve. When it comes to selecting your springs, if you have several to choose from, choose a sufficiently stiff set. If you have the choice between sets that are more curved vs. those that are straighter, choose the straighter ones. If you have the choice between sets that are longer or shorter in overall length, either one will work, but you’ll have to consider whichever length you choose as you lay out the distance between the center post, the anvil and the drive wheel. The length of your spring pack coupled with your stroke length will impact the speed at which your hammer will safely run. The spring action and whip action of the spring set during cycling increase head speed at contact, which improves performance.
The author used a set of leaf springs for the rocker arm of his power hammer. The arm is also called a helve.
Your spring set needs to swivel or rock on top of your center post. I built my hammer with the springs riding on top of the shaft, and the shaft riding in pillow block bearings. Others are built with flange bearings, and others with the shaft above the springs. Any configuration is fine provided you have the clearance you need for the springs to rock back and forth as the hammer operates.
Your spring set will need a swivel on the end where it connects to the pitman arm (the rod that connects the spring arm to the drive wheel). Like the top pivot, there are as many different designs as there are guys building hammers.
The end of the spring set near the hammer head needs to be connected in a way where the arc of the spring travel is converted into direct linear up and down energy. Again, there are multiple ways to accomplish this. I went with a set of rollers on the hammer head, and the spring rides in and out on the rollers as it arcs up and down. I have seen designs with toggle linkage as well.
Hammer Head And Tup
The entire assembly that makes up the hammer head is called the tup. When a smith says he has a 25-pound power hammer, he’s referring to the tup weight. You are looking for a tup weight that is roughly 1/10 of your anvil weight. I built my hammer with a piece of 2-inch-solid-square stock long enough to make a 40-pound tup. For heads that weigh less, you can use a piece of solid stock for the contact area, and tubing or pipe to make up the extra length you need. While a solid anvil is critical to the function of the hammer, the hammer head itself only needs to be solid on the striking end to properly transfer the force.
The DIY spring helve hammer built freestyle by Doug Davis of Lubbock, Texas, is shown in both instances here from the pulley side.
The tup rides up and down in a set of guides. You’re converting an arcing spring movement into a linear up-and-down hammer movement. One consideration is that your guides need to account for lateral movement in all four directions. The simplest way is for the guide to completely enclose the hammer shaft. Contact surfaces between the hammer head and guide should be lubricated, and steel on steel is not advised. Bearing surfaces should be made of UMHW (Ultra High Molecular Weight Polyethylene) plastic or of bronze. These surfaces benefit from a degree of adjustability to make sure that the hammer head is aligned properly with the anvil.
I used set screws and a UMHW plastic cutting board on my hammer, with lithium grease as well. My hammer runs well with fresh grease and less well without. I grease the hammer shaft at the beginning of every forging session. The vertical position and length of your guides should accommodate the various stroke lengths of your hammer. You don’t want the hammer head hitting the bottom of the guide on the upstroke, nor the spring connector hitting the top of the guide on the downstroke.
Pitman Arm
A stiff arm connects the spring pack to the rotating wheel, converting the rotary action of the flywheel to a straight up-and-down rocking motion. This arm is called a pitman arm. It is adjustable for length, as the dimension will ultimately be changed as you tune your hammer by trial and error, or as you adjust your hammer to accommodate varying thicknesses of stock, or the use of swages, or top and bottom tools. I used a toggle linkage on the top and for the bottom of the arm I used large bolts welded to a piece of plate, which I then bolted to the hub of the tire used for a clutch. This is another area where your available parts and mechanical experience will dictate your design.
So, you’re going to build a power hammer… now’s the time to consider where to get your parts.
The first thing you’ll have to decide is which style of power hammer you will build. There are as many designs as there are folks who build hammers, but they fall into two basic categories: helve hammers and linkage hammers.
Power Hammer Styles
Linkage Hammer
At the basic level, a helve hammer has an arm that moves up and down on a fulcrum to move the hammer head up and down. A linkage hammer uses a wheel, tire or disk that rotates and uses the rotation to move the hammer head up and down. The Little Giant power hammer design uses a linkage, as does the commonly home-built tire hammer.
The Little Giant power hammer design uses a linkage, as does the commonly home-built tire hammer. ABS master smith/BLADE® field editor Joe Szilaski pounds away with his 50-pound Little Giant. (Lori Szilaski image)
Helve Hammer
I chose to build an Appalachian-style spring helve hammer because I had access to a variety of leaf springs, and because the design is more intuitive and less mechanically precise. I figured correctly that I could build a helve hammer design from scratch, but that a tire hammer had some engineering points that would be difficult for me to figure out. If you have access to uniform steel sizes or must buy your steel, I suggest a tire hammer. I had good scrap steel and didn’t want to buy much.
I’m focusing on the upright, heavier, more efficient metal-moving machines. Even so, it’s worth mentioning the smaller, simpler but less efficient helve hammers. I came across a good example in the shop of Shawn Moulenbelt, a Michigan bladesmith who was on season seven of Forged in Fire. His hammer used various sizes of hollow square tubing, a sledgehammer head and a half-horsepower motor. He used a slack belt clutch and interchangeable die plates. His hammer was built by Rusty Glovebox on YouTube and is a solid DIY (do-it-yourself) design.
Bladesmith Shawn Moulenbelt’s helve hammer uses various sizes of hollow square tubing, a sledgehammer head and a half-horsepower motor. On the upside, these hammers are quick and fairly straightforward to build. On the downside, they’re not all that great at their one job: moving metal. Even so, a similar light use-DIY power hammer is much more efficient than your arm, and much less likely to get tired.
On the upside, helve hammers are quick and fairly straightforward to build. On the downside, they’re not all that great at their one job: moving metal. Even so, a similar light use-DIY power hammer is much more efficient than your arm, and much less likely to get tired. In my mind, if you have the time and skill to build a small hammer, you can just as easily build a bigger one. Even so, the small helve hammers may be just the ticket for your shop.
The author’s home-built hammer combines a 5-inch piece of round stock with a heavy sleeve from a “mud pump” to make an anvil that weighs around 400 pounds.
Resourcing An Anvil
There are many different things that can make a suitable anvil for a power hammer and many more things that cannot. What you are looking for in an anvil is a solid piece of steel that weighs anywhere from 150 to 600-800 pounds, which can be difficult to acquire.
Sometimes you can find solid square or round bar steel. Some folks recommend railroad axles. Others suggest forklift tines welded together. I’ve seen sections of a 2-inch square bar welded together into a solid 6×6. I’ve seen pieces of 1-inch plate welded where the hammer strikes the ends. Whatever you can find needs to be solid or able to be welded into a solid, single, massive piece, and your welder has to have the power to stick it all together. My hammer is built on a 32-inch piece of 5-inch round bar welded inside a mud pump sleeve that has a 5-inch bore. The total weight of my anvil is around 400 pounds.
What Not To Use
Don’t be tempted to think you can get a piece of something hollow like pipe or square tubing and fill it up and make a suitable anvil. Each stroke of your hammer pounds the steel in-between the hammer head and your anvil, pushing your anvil toward the ground. If you have any movement, vibration or give in your anvil, the force is absorbed by the movement and not efficiently transferred to your workpiece.
Anvil To Hammer Head Ratio
When you finally locate this difficult-to-find thing, it won’t likely be the size or shape you want. My anvil was round, which doesn’t easily weld to square tubing, for example. I had to deal with it. As noted, my anvil was around 400 pounds total weight. Yours may be more or less. You should design your hammer with a minimum 1:10 head-to-anvil ratio. Since I had a 400-pound anvil, I built a 40-pound head. If all you can find is a 200-pound hunk of steel for your anvil, you should stick to a 20-pound head or so. Design your hammer around your anvil, as the anvil is the hardest part to find. Alternatively, find the weight you need for the anvil and use the tire hammer plans.
Another consideration is the base for your hammer. I’d recommend the thickest steel plate you can find, mounted on the firmest foundation you can muster. If I could have built on 1-inch plate and bolted it to a 24-inch-deep concrete pad set into a concrete shop floor, I’d have done it. I had to make do with what I could find in my “free” scrapyard, and deal with the limitations of my shop setting.
Power Hammer Center Post
For any hammer you need a center post. The post should be heavy enough to withstand the extreme forces involved in rocking a spring arm or linkage with a heavy hammer on one end. I used a piece of 4-inch tubing with half-inch walls. Others have used thinner-walled but larger cross-section square or rectangular tubing, heavy walled pipe or sections of I beam. The tire hammer plans call for a 6-foot-long piece of quarter-inch wall and 5-inch square tubing.
Final Cut
Another consideration is the base for your hammer. The author scored some 2-inch-thick, 30-inch-round, 300-pound base plates out of the “drop” pile at a local steel distributor, along with several other potential anvils.
My power hammer has become an essential tool in my shop, to the point that I sometimes wonder how I ever lived without it. I have only begun to explore its full potential. I built it for my appearance on Forged in Fire, where I was fortunate to make the final. I was able to come home and use my hammer to build my final edged piece for FIF. I lost the contest but ultimately still have a power hammer, and I can still take pride in the fact I built it myself from little more than a pile of junk.
It may take you a few months to gather all the primary parts, or you may get lucky and find them all in one place. Next month’s article will focus on building considerations for a spring helve hammer, and later we’ll discuss the Clay Spencer DIY tire hammer.
