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Olson Manufacturing – Featured Customer

Featured Image Courtesy of Logan Olson, Olson Manufacturing

Located in northern California, Olson Manufacturing specializes in handcrafted, customizable golf products that are made with utmost attention to detail from the highest quality materials. Logan Olson, its owner, was introduced to the game of golf by his grandparents at a young age and fell in love with the sport, especially how individualized it is, and how one’s own effort and dedication is paramount. It is because of this love of golf that Logan began designing, and making, his own putters. Soon after, Olson Machining was born.

Now with years under his belt, Logan took time to reflect about Olson Manufacturing, his passion for golf, high-quality tooling, and where his inspiration for his designs originated.

Photo Courtesy of: Logan Olson, Olson Manufacturing

How did you get started and learn how to machine?

I got started in manufacturing coincidentally with making putters: A project that went from a solely digital design to learning a CAD program. It turned into something I wanted to bring into tangible space. A friend of mine introduced me to a manual machinist that had a small machine shop at his house. He had just purchased a personal hobby-sized CNC machine and was kind enough to let me hobble my way through learning the fundamentals of machining on it to design a putter. A year later, I held a barely recognizable chattery mess of a putter and my journey was just beginning.

Where does your passion for golf come from?

I was introduced to the game of golf early on by my grandparents. The individual nature of the game, surrounded by the need to depend on your own effort and dedication as a means to success, has really paved the way for me as a business owner. The need for honesty and integrity, even when it might be easier to take the other road out, has allowed me to stick through the challenging aspects of creating a machine shop and allow my business to thrive in this fast pace, ever-changing world.

What is the inspiration in your designs?

From a design aspect, my number one priority is to do my absolute best to execute the task of creating the best putter I can for the end-user. Customization, additional design aspects, as well as other details, are a welcome addition to a putter that will perform at the highest level. When it comes to the design of creating a custom build, I try to forget that the piece I am working on is a putter altogether and pull my inspiration from other places and different crafts.

It’s always fun when people ask what I do as a machinist to tell them I make golf clubs. There’s always a hesitant humorous laugh as they respond with an, “oh that’s nice, or good for you”. That always seems to change as soon as I show them what I actually make.  The following response is usually more on the stream of “you seriously make these, or wow, that’s not at all what I expected.” The detailed craftsmanship of sword makers, clockmakers, and jewelers is where I try to pull my main inspiration from.

 I do a lot of commissioned work for customers ordering a specific putter that they themselves design, however, I think my true voice as an artist and machinist lies with the putters I make where the designs can flow out of my own imagination with no guidelines or restrictions.

What is your favorite putter you’ve designed?

I’ve had the opportunity to create a ton of really cool and unique projects in my years as a putter maker. It’s really hard to pick out a favorite. I try to say that my favorite putter I’ve ever made is the one I’m currently working on or excited about. I could probably make a list of the top 20 maybe, but picking an individualistic favorite would be tough.

Who is the most famous contact that you have worked on a project with?

I’ve been lucky enough to work with a handful of professionals on the PGA tour as well as the LPA tour and Web.com tours. Feedback from this caliber of players is really the driving force of development for what I do. They can offer some of the most keynotes that help drive changes every year. I have a hard time picking apart a favorite project, but every time a professional golfer comes aboard I always seem to learn something new.

What sets Olson Manufacturing apart from the competition?

In a world where mass production and system efficiency control the consumer market, utilizing old world craftsmanship in companion with cutting edge technology, I can create one of a kind personalized and unique products. That’s not a touch you can find buying something off of a shelf. Knowing that only 1 pair of hands might have spent hours, days, even weeks just creating a putter, I think is something a person holds value to once they acquire one of my putters.

What machines do you currently have in your shop and what materials are you machining?

I use all vertical mills at my shop. With the exception of one of my largest machines, having a 4th axis. Everything I run is all 3 axis machining. I really cut everything under the sun. The bulk of my machining consists of stainless steel, mild alloy carbon steel, and aluminum, for fixture making. However, with that said, I do a very large amount of copper as well. The bulk majority of my inlay work is done in superalloys and some exotic blends such as Zirconium-Titanium alloys, Titanium Damascus (Timascus), pre-hardened high carbon Damascus steels, mother of pearl, bronze, and a handful of other materials.

Why is high quality tool performance important to you?

When I’m working in an environment where the part I am making is a one-shot kind of deal or the material is incredibly hard to get/ expensive, not having the ability to remake the part is why customer support and applications engineers are indispensable. When you’re off purchasing a cheap tool from an unknown company you are unlikely to be able to pick up the phone and say “hey, I’ve got a .030” tool going 1” deep in titanium, this tool can’t break haha can you help me out?”

I can count back just in the last year at least a dozen times I’ve spoken with a Harvey Tool rep on one of my micro tools for a cutting recipe recommendation for an application that kept me out of the dog house. I think we could all talk about coating, cutting life, and tool performance all day long, but I could argue that being able to make a phone call and have an engineer reassure you something will work, is the most important thing of all when it comes to quality tool performance.

What is the smallest Harvey tool you have used and the largest Helical tool?

I’ve used a .02” diameter 3 flute tool for stainless and carbon steel, which would likely be the smallest. I regularly store a .04” tool in my tool changer for pocketing on small inlay work. I used to be scared to sneeze on them in fear of them breaking, now they’re as dependable as any tool in my library and I require them daily for all kinds of machine work. The largest tool I run from Helical is a 6 flute ½” endmill for HEM roughing. I find that’s really as large as I need to go.

If heavier cutting is necessary I’ll lean on an insert tool. I really think some people would be amazed though, at the MRR you can get with a ½” tool. These modern toolpaths are incredibly powerful in comparison to some of the older style machining strategies. Give me a ½” tool in stainless full depth at 250 inches a minute and I can move some metal.

Can you talk about a time that Harvey Tool or Helical products really came through and helped your business?

This would go back to one of my earlier answers for the customer support argument. I was running a billet of pre-hardened Damascus steel for a putter I was making. I don’t know if you’re familiar with Damascus at all, but if you picture high carbon steel blended, smashed, and forged together with a nickel alloy, then hardened, I think you can paint a picture. Oh yeah, and nickel alloys are famously fun to machine… think Inconel, Monel, and Hastelloy… fun stuff. So take that billet and make a putter out of it haha.

Anyways, this stuff is harder than a coffin nail and is eating my 80 dollar endmills for breakfast like it skipped dinner the night before. I was down to my last ½” tool that could do the machine work on this putter and didn’t know what I was going to do. I called up Helical, and an applications engineer not only gave me a recipe that ended up saving me but sent me the skew for a tool that worked way better than the one I had in the spindle. I ordered a package of them, and ever since that day, they are my go-to in Damascus.

If you could give one piece of advice to a new machinist ready to take the #PlungeIntoMachining, what would it be?

My biggest piece of advice would be to learn as much as you can. In today’s world, the internet is an incredibly powerful tool and platform for the machining community. There is basically a video out there somewhere you can watch that can probably answer any question you might have. It’s insane. I’m 24 years old and started as a machinist at 19-20. There is absolutely no way I could have gotten to where I am today without countless hours of YouTube scrolling and video binge-watching. It’s great stuff and you should soak it in like a sponge as fast as you can. 30 years ago the machinists would look at the stuff we are doing today and call it Wizardry. We truly are living in an incredible time. Live, learn and love what you do.

To see more of Logan and Olson Manufacturing, you can follow him on Instagram @olsonmfg

Workshops for Warriors – Featured Customer

Featured Image Courtesy of Workshops for Warriors

In 2008, Hernán Luis y Prado, a United States Navy officer, noticed his fellow service members looking for a successful path in life after service. Hernán decided he needed to make a change. He set out to make a difference for his fellow service members by starting Workshops for Warriors, a state-licensed, board governed, fully audited, nonprofit school. Its mission is to provide quality training, accredited educational programs, and opportunities for its students to earn third-party nationally recognized credentials to enable Veterans, transitioning service members, and others to be successfully trained and placed in their chosen advanced manufacturing career field.

We had the honor of speaking with Marine Veteran Scott Leoncini, an instructor at Workshops for Warriors, about the accomplishments and amazing work Workshops for Warriors does for our Veterans.

What Does Workshops for Warriors Offer for Our Veterans?

Workshops for Warriors offers two primary tracks of training, both taught by Veterans: welding and machining, Scott explained. After choosing a track, students become a part of the 16-week accelerated program. Those with only a minimum of four months and one nationally-recognized certification can walk across the shipyards and gain employment. Workshops for Warriors remains committed to providing free training to Veterans who do not have access to living-wage jobs. U.S. Veterans often face challenges as they transition to civilian life, including significant barriers to civilian employment. In addition to the hard technical skills, our students are also learning soft skills such as attitude, communication, work ethic, teamwork, time management, problem-solving, critical thinking, and conflict resolution.

A proven path into a rewarding career can eliminate problems like unemployment, homelessness, broken families, and suicide. The problem of Veteran unemployment does not have easy, short-term solutions. Workshops for Warriors is uniquely positioned to expand proven innovative techniques to give Veterans marketable employment that will allow them to build careers and families. 

How Did You Find Workshops for Warriors and Become an Instructor?

After I left the Marines in 2009, after serving two tours in Iraq as a combat engineer, I desired an action-packed career. I thought my best option was to start a career in law enforcement. I got a job at a security company and worked there for a few years. During this time, a close friend of mine tragically passed away in a helicopter crash, leaving behind his pregnant wife. This made me reevaluate my current life with my wife and two children. I decided I didn’t need that action-packed career, and that my family comes before anything.

Another friend of mine actually told me about Workshops for Warriors and how it was giving him career skills in welding, and he talked about a machining program. When I showed up, I had no idea what was in store for me. I started learning all about CNC machines, and how to program and run these things. It was eye-opening and I was having a great time. After my first semester, I was asked to become a teacher’s assistant and I’ve been teaching here now for almost five years.

Where Does Your Passion for Teaching Come From?

I love teaching Veterans and helping them transition so they don’t have to go through the same five years I did of, “What am I going to do with my life?” I’ve gone through the same situation a lot of the people coming to us are currently in.

I think that there are three fundamentals that anyone looking for a career or path can apply to their lives and be successful. You have to show up on time, you have to work hard, and you have to be willing to learn. I didn’t know anything about machinery when I first got into this field. When I went through it as a student myself, I applied those three things to my work habits, and now I’m an instructor. I had pigeonholed myself for a long time. But you have to recognize that there’s always something else, something up next and that’s what I want to help teach the Veterans who come through here.

What Courses Does Workshops for Warriors Provide?

We offer many different courses, including CAD courses in Solidworks and CAM courses in Mastercam, and we offer welding courses for Gas Metal and Flux Cored Arc Welding. We also offer advanced training in Flowmaster Programming and Waterjet Operation, 3D Printing, and Robotics. With these courses, we offer many credentials to start a real career. The machining program is accredited by the National Institute for Metalworking Skills (NIMS). NIMS is recognized by the United States Department of Education. The welding program is accredited by the American Welding Society (AWS), which is the worldwide leader in certification programs for the welding industry.

Thanks to private donors, Veterans and transitioning service members are able to become trained and certified in our advanced manufacturing programs. Students can apply to enter one of our programs, or take specific classes that meet their needs.

What Jobs Have You Seen Veterans Acquire After Workshops for Warriors?

We have seen many success stories from Veterans once they leave Workshops for Warriors. One Veteran, in particular, visited us in search of direction in 2019. The machining program had one spot left for the semester, so he took it. He is now certified in machining and welding. He entered a job market that was struggling after his graduation. But he still had a job lined up with 5th Axis Machining in San Diego. His future plans are to own his own business to support his family.

How Could People Help Support Workshops for Warriors?

They can donate directly to us on our website, or on our Facebook page. Or, people looking to help support us can reach out to us by email, [email protected], or by calling us at 619-550-1620, with any questions. We also accept equipment donations for each program, welding, and machining. You can also support us by following on Facebook, Instagram, Twitter, LinkedIn, YouTube, or our newsletter.

What Advice Would you Give to Anyone Looking to Start a Career Path?

After leaving the service, I fell into a depression. I kept thinking, “I’ll never be as good as I was back then.” It was hard to not have “Marine” be the primary part of my identity, so I became blinded by my obsession with still being the superhero kicking down doors. Don’t paint yourself into a corner. Be flexible and make sure to show up on time, work hard, and be willing to have an open mind and ready to learn. Test your comfort zone. When I left the service, I only knew how to be the man with the gun. Workshops for Warriors gave me a chance to be more than that – it gave me a direction in life. I now get to do what I love and help my fellow Veterans.

To learn more about Workshops for Warriors and their mission you can visit their website or follow them on Instagram, Facebook, LinkedIn or Twitter.

Causes & Effects of Built-Up Edge (BUE) in Turning Applications

In turning operations, the tool is stationary while the workpiece is rotating in a clamped chuck or a collet holder. Many operations are performed in a lathe, such as facing, drilling, grooving, threading, and cut-off applications. it is imperative to use the proper tool geometry and cutting parameters for the material type that is being machined. If these parameters are not applied correctly in your turning operations, built-up edge (BUE), or many other failure modes, may occur. These failure modes adversely affect the performance of the cutting tool and may lead to an overall scrapped part.

When inspecting a cutting tool under a microscope or eye loupe, there are several different types of turning tool failure modes that can be apparent. Some of the most common modes are:

  • Normal Flank Wear: The only acceptable form of tool wear, caused by the normal aging of a used cutting tool and found on the cutting edges.
    • This abrasive wear, caused by hard constituents in the workpiece material, is the only preferred method of tool wear, as it’s predictable and will continue to provide stable tool life, allowing for further optimization and increased productivity.
  • Cratering: Deformations found on the cutting face of a tool.
    • This tool mode is a chemical and heat failure, localized on the rake face area of the turning tool, or insert. This failure results from the chemical reaction between the workpiece material and the cutting tool and is amplified by cutting speed. Excessive Crater Wear weakens a turning tool’s cutting edge and may lead to cutting edge failure.
  • Chipping: Breaking of the turning tool along its cutting face, resulting in an inaccurate, rough cutting edge.
    • This is a mechanical failure, common in interrupted cutting or non-rigid machining setups. Many culprits can be to blame for chipping, including machine mishaps and tool holder security.
  • Thermal Mechanical Failure (Thermal Cracking): The cracking of a cutting tool due to significant swings in machining temperature.
    • When turning, heat management is key. Too little or too much heat can create issues, as can significant, fast swings in temperature (repeated heating and cooling on the cutting edge). Thermal Mechanical Failure usually shows in the form of evenly spaced cracks, perpendicular to the cutting edge of the turning tool.
  • Built-Up Edge (BUE): When chips adhere to the cutting tool due to high heat, pressure, and friction.

Effects of Built-Up Edge in Turning Application

A built-up edge is perhaps the easiest mode of tool wear to identify, as it may be visible without the need for a microscope or an eye loupe. The term built-up edge means that the material that you’re machining is being pressure welded to the cutting tool. When inspecting your tool, evidence of a BUE problem is material on the rake face or flank face of the cutting tool.

built up cutting edge on turning tools
Image Source: Carbide inserts Wear Failure modes. | machining4.eu, 2020

This condition can create a lot of problems with your machining operations, such as poor tool life, subpar surface finish, size variations, and many other quality issues. The reason for these issues is that the centerline distance and the tool geometry of the cutting edge are being altered by the material that’s been welded to the rake or flank face of the tool. As the BUE condition worsens, you may experience other types of failures or even catastrophic failure.                     

Causes of Built-Up Edge in Turning Applications

Improper Tooling Choice

Built-Up Edge is oftentimes caused by using a turning tool that does not have the correct geometry for the material being machined. Most notably, when machining a gummy material such as aluminum or titanium, your best bet is to use tooling with extremely sharp cutting edges, free cutting geometry, and a polished flank and rake face. This will not only help you to cut the material swiftly but also to keep it from sticking to the cutting tool.

various turning tools

Using Aged Tooling

Even when using a turning tool with correct geometry, you may still experience BUE. As the tool starts to wear and its edge starts to degrade, the material will start building up on the surface of the tool. For this reason, it is very important to inspect the cutting edge of a tool after you have machined a few parts, and then randomly throughout the set tool life. This will help you identify the root cause of any of the failure modes by identifying them early on.

Insufficient Heat Generation

Built-up edge can be caused from running a tool at incorrect cutting parameters. Usually, when BUE is an issue, it’s due to the speed or feed rates being too low. Heat generation is key during any machining application – while too much heat can impact a part material, too little can cause the tool to be less effective at efficiently removing chips.

4 Simple Ways to Mitigate BUE in Turning Applications

  1. When selecting a tool, opt for free cutting, up sharp geometries with highly polished surfaces. Selecting a tool with chipbreaker geometry will also help to divide chips, which will help to remove it from the part and the cutting surface.
  2. Be confident in your application approach and your running parameters. It’s always important to double-check that your running parameters are appropriate for your turning application.
  3. Make sure the coolant is focused on the cutting edge and increase the coolant concentration amount.
  4. Opt for a coated Insert, as coatings are specifically engineered for a given set of part materials, and are designed to prevent common machining woes.
solid carbide turning tool

Heavy Duty Racing – Featured Customer

Featured Image Courtesy of Pete Payne, Heavy Duty Racing

Heavy Duty Racing is a manufacturing company based in Stafford, VA, that specializes in motocross, off-road motorcycle suspension, and 2-stroke engine modification. Its owner, Pete Payne, grew up racing motorcycles. Later in life, he even taught classes on how to race. Simply, Motocross and motorcycles became Pete’s passion.

Pete always looked for ways to enhance his motorcycle’s engine, but quickly realized that no shops in his area could design what he was looking for. To get access to the parts he would need, he would have to rely upon companies from far away, and would oftentimes be forced to wait more than three weeks for them to arrive. Because of this, Pete decided he would need to take part manufacturing into his own hands. He purchased a manual lathe, allowing him to make modifications to his two-stroke engines exactly how he wanted them. Quickly thereafter, Heavy Duty Racing was born.

Pete discussed with us his love of racing, how he first got into machining, the parts his shop has designed, and tips and tricks for new machinists.

Pete Payne Heavy Duty Racing
Photo Courtesy of: Pete Payne, Heavy Duty Racing

How did you get started in machining?

Since I was a kid I have been riding motorcycles and racing motocross. I went to a tech school in the ’80s and learned diesel technologies. When I realized nobody in this area could help design the engines I wanted to make, I decided I needed to learn how to do it myself. I have a friend, George, who is a retired mold and die maker that also worked on motorcycle engines, I asked him for some advice on how to get started. George ended up teaching me all about machining and working on engines. I really learned from failures, by trying new things, and doing it every day. I started Heavy Duty Racing in 1997 and we have been modifying and designing the highest performing engines since then.

turning motorcycle part on lathe
Photo Courtesy of: Pete Payne, Heavy Duty Racing

What machines and softwares are you using in your shop?

We currently have a Thormach PCNC 1100 and a Daluth Puma CNC Lathe (we call it The Beast, it’s angry and grumpy but it gets the job done). We also have a Bridgeport Mill, Manual Lathe, and a Tiggwell. When we were choosing software to use, they had to be easy and quick to learn. We weighed our options and decided to use Autodesk Fusion 360 about 5 years ago. We mostly machine cast iron and steel since most engines are made from those materials.

What sets Heavy Duty Racing apart from competitions?

We have a small hands-on approach and treat every part with care. We don’t have a cookie-cutter process so we are very flexible when it comes to customer needs. Since each part is different, we don’t have set prices and have custom quoting on each part. We value our customers and tailor every build to the rider, based on the weight, fuel, and skill level of the rider. We make unique components for each rider so they can have the best experience when they hop on their bike. We are just focused on letting people do what they love.

metal racing parts made by Heavy Duty Racing
Photo Courtesy of: Pete Payne, Heavy Duty Racing

What is the coolest project you have worked on?

In 2016, MX Tech Suspension in Illinois gave us the opportunity to build an engine for them to display at their event. We got to go to California to watch them demo the engine in front of thousands of people. It was very nerve-racking to watch it live but the experience was amazing. The engine was later featured on the cover of Motocross Action magazine. It was very cool to see something we dedicated so much hard time toward get that much recognition.

Why is high quality tooling important to you?

We are making really difficult machine parts so we need tools that can last. Micro 100 tooling lasts and does the job. The thread mills we use are 3-4 mm and 14 mm and they last longer than any competition out there. The thread mills do not chip like the competition and the carbide is super strong. Breaking a tool is not cheap, so to keep one tool in the machine for how long we have has really saved me in the long run. We found Micro 100 one day looking through our distributor’s catalog and decided to try some of their boring bars. After about 5 holes, we realized that these tools are the best we have ever used! Micro has had everything I’ve been looking for in stock and ready to ship, so we have yet to need to try out their custom tools.

Most engine tolerances are no more than .0005” taper. You need the tooling to hold tight tolerances, especially in engines. Just like with tooling, minimizing vibration is key to getting the engine to last longer. We need tight tolerances to maintain high quality and keep engines alive.

machined metal racing part
Photo Courtesy of: Pete Payne, Heavy Duty Racing

If you could give one piece of advice to a new machinist ready to take the #PlungeIntoMachining, what would it be?

The same advice I’ve given to my son: Don’t be ashamed to start from the bottom and learn from the ground, up. Everybody wants to make cool projects, but you need to learn what is going on around you to master the craft. Learn the processes and follow the steps. It’s very easy to break a tool, ruin a part, or even hurt yourself. Don’t be scared of quality tools! Buying the cheap stuff will help you with one job, but the quality tools last and will save you in multiple situations.

Follow Heavy Duty Racing on Instagram, and go check out their website to see more about them!

Achieving Success in CNC Woodworking

Developing a Successful Cutting Direction Strategy

There are a number of factors that can affect the machining practices of wood in woodworking. One that comes up a lot for certain hardwoods is the cutting direction, specifically in relation to the grain pattern of the wood. Wood is an anisotropic material. This means that different material properties are exhibited in different cutting directions. In terms of lumber, there are different structural grades of wood related to grain orientation. If the average direction of the cellulose fibers are parallel to the sides of the piece of lumber, then the grains are said to be straight. Any deviation from this parallel line and the board is considered to be “cross-grain”. Figure 1 below depicts a mostly straight grain board with arrows indicating the different axes. Each of these axes exhibits different sets of mechanical properties. Because of these differences, one must be conscious of the tool path in woodworking and minimize the amount of cutting forces placed on the cutter in order to maximize its tool life.

straight grain wood board with woodworking axes
Figure 1: Mostly straight grain board with arrows indicating different axes

Cutting perpendicular to the grain is known as cutting “across the grain” in woodworking. In Figure 1 above, this would be considered cutting in the radial or tangential direction. Cutting parallel to the grain is known as cutting “along the grain” (longitudinally in terms of Figure 1). The closer you are to cutting at 90° to the grain of the wood in any direction, the larger the cutting force will be. For example, a tool with its center axis parallel to the tangential direction and a tool path along the longitudinal direction would have less wear than a tool with the same center axis but moving in the radial direction. The second type of tool orientation is cutting across more grain boundaries and therefore yields greater cutting forces. However, you must be careful when cutting along the grain as this can cause tear-outs and lead to a poor surface finish.

The Proper Formation of Wood Chips With CNC Woodworking

When cutting wood parallel to the grain, there are three basic types of chips that are formed. When cutting perpendicular to the grain, the chip types generally fall into these same 3 categories, but with much more variability due to the wide range in wood properties with respect to the grain direction.

Type 1 Chips

Type 1 chips are formed when wood splits ahead of the cutting edge through cleavage until failure in bending occurs as a cantilever beam. A large force perpendicular to the shear plane is produced, causing the wood ahead of the cutting edge to split, forming this tiny cantilever beam. When the upward force finally exceeds the strength of this tiny beam, it breaks off.  These types of chips cause comparatively little wear compared to types 2 and 3, as the material is splitting before coming in contact with the pointed edge. End mills with either extremely high rake or very low rake angles often produce type 1 chips. This is especially true when machining against grain slopes that are greater than 25°. Woods with moisture content less than 8%form discontinuous chips and are at a higher risk of tear-out.

Type 2 Chips

Type 2 chips are the most desirable of the three types in terms of surface finish. They are a result of material failure along a diagonal shear plane, extending from the cutting edge to the workpiece surface. Type 2 chips form when there is a proper balance between the properties of the wood, cutting parameters, and cutter geometry. Woods with a moisture content between 8% and 20%have a much higher chance of forming continuous type 2 chips while leaving a good surface finish.

Type 3 Chips

The last type of chip forms when the rake angle of a cutter is much too low. In this scenario, the cutting force is almost parallel to the direction of travel. This causes a soft material, such as wood, to be crushed rather than sheared away, leaving a poor surface finish. Generally, the surface left behind looks like tiny bundles of wood elements, a surface defect commonly known as “fuzzy grain.” This type of chip occurs more frequently in softwoods as the crushing situation is compounded in low-density woods.

types of wood chips in woodworking
Figure 2: Different types of wooden chips

Extending Tool Life When Woodworking

Speeds & Feeds Rules of Thumb

There are several different categories of tool wear that occur when cnc woodworking. General rules of machining still apply as RPM has the greatest influence on wear rate. Over-feeding can increase tool wear exponentially and also cause tool breakage. As with most machining operations, a balance between these two is essential. If you are looking to increase your productivity by increasing your speed, you must increase your feed proportionally in order to maintain a balance that keeps the tool properly engaged in the material.

Proper Management of Heat

When cutting tools are exposed to high heat, they begin to wear even faster, due to corrosion. The cobalt binder within most carbide tools on the market begins to oxidize and break free of the cutting edge. This sets off a chain reaction, as when the binder is removed, the tungsten carbide breaks away, too. Different species of wood and types of engineered wood have different corrosive behaviors at high temperatures. This is the most consistent type of wear that is observed when machining MDF or particleboard. The wear is due to the chlorine and sulfate salts found in adhesives as this accelerates high-temperature corrosion.  As with aluminum, when the silica content of a wood increases, so too does its corrosiveness.

Generally, increased tool wear is observed in wood with high moisture content. This trait is due to the increased electro-chemical wear caused by the extractives in wood., Moisture content in wood includes substances such as resins, sugars, oils, starches, alkaloids, and tannins in the presence of water. These molecules react with the metallic constitutes of the cutting tool and can dull the cutting edge. Carbide is more resistant to this type of wear compared to high-speed steel.

Best Coatings for Extended Tool Life in Wood

If you want a longer-lasting tool that will maintain its sharp cutting edge (and who doesn’t), you may want to consider an Amorphous Diamond coating. This is an extremely abrasive resistant coating meant for non-ferrous operations in which the temperature of the cutting zone does not exceed 750 °F. This coating type is one of Harvey Tool’s thinnest coatings, therefore minimizing the risk of any edge rounding and maximizing this edge’s durability.

Avoiding Common Woodworking Mishaps

Tear Out

Tear out, sometimes called chipped grain or splintering, is when a chunk of the wood material being machined tears away from the main workpiece and leaves an unappealing defect where it used to be. This is one of the most common defects when machining wood products. There are many different reasons that tear out occurs. Material characteristics are something to be considered. Tear out is more likely to occur if the grain orientation is less than 20°relative to the tool path, the moisture content of the wood is too low, or the density of the wood is too low. Figure 4 shows the grain orientation angle relative to the tool path. In terms of machining parameters, it can also occur if either the chip load, depth of cut, or rake angle is too high.

woodworking grain in relation to tool path
Figure 4: Example of grain orientation angle relative to the tool path

Fuzzy Grain Finish

Fuzzy grain looks like small clumps of wood attached to the newly machined face and occurs when the wood fibers are not severed properly. Low rake or dull cutting tools indent fibers until they tear out from their natural pattern inside, causing type 3 chips to form, resulting in a poor finish. This can be exacerbated by a low feed or depth of cut as the tool is not properly engaged and is plowing material rather than shearing it properly. Softer woods with smaller and lesser amounts of grains are more susceptible to this type of defect. Juvenile wood is known to be particularly liable for fuzzy grain because of its high moisture content.

fuzzy grain wood finish
Figure 5: Example of a fuzzy grain finish

Burn Marks

Burn Marks are a defect that is particularly significant in the case of machining wood, as it is not generally a concern when machining other materials. Dwelling in a spot for too long, not engaging enough of the end mill in a cut, or using dull tools creates an excessive amount of heat through friction, which leaves burn marks. Some woods (such as maple or cherry) are more susceptible to burn marks, therefore tool paths for these types should be programmed sensibly. If you are having a lot of trouble with burn marks in a particular operation, you may want to try spraying the end mill with a commercial lubricant or paste wax. Be careful not to use too much as the excess moisture can cause warping. Increasing your tool engagement or decreasing RPM may also combat burn marks.

burn marks from wood cutter
Figure 6: Example of burn marks

Chip Marks

Chip marks are shallow compressions in the surface of the wood that have been sprayed or pressed into the surface. These defects can swell with an increase in moisture content, worsening the finish even more. This type of blemish is generally caused by poor chip evacuation and can usually be fixed by applying air blast coolant to the cutting region during the operation.

Raised Grain

Raised grain, another common defect of woods, is when one or more portions of the workpiece are slightly lower than the rest. This blemish is particularly a problem when machining softer woods with dull tools as the fibers will tear and deform rather than be cleanly sheared away. This effect is intensified when machining with slow feeds and the wood has a high moisture content. Variations in swelling and shrinking between damaged and undamaged sections of wood exacerbate this flaw. It’s for this reason that raised grain is a common sight on weather-beaten woods. Work holding devices that are set too tight also have a chance of causing raised grain.

Differentiating Harvey Tool Wood Cutting & Plastic Cutting End Mills

Woodworking Upcut End Mill
Harvey Tool Upcut End Mill For Wood

https://www.harveytool.com/products/material-specific-end-mills/woodMachinists oftentimes use Plastic Cutting End Mills for woodworking, as this tool has very similar internal geometries to that of an End Mill for Wood. Both tools have large flute valleys and sharp cutting edges, advantageous for the machining of both plastic and wood. The main difference between the Harvey Tool plastic cutters and the woodcutters is the wedge angle (a combination of the primary relief and rake angle). The woodcutter line has a lower rake but still has a high relief angle to maintain the sharpness of the cutting edge. The lower rake is designed to not be as “grabby” as the plastic cutters can be when woodworking. It was meant to shear wood and leave a quality surface finish by not causing tear-out.

Harvey Tool’s offering of End Mills for Wood includes both upcut and downcut options. The upcut option is designed for milling natural and engineered woods, featuring a 2-flute style and a wedge angle engineered for shearing wood fiber materials without causing tear out or leaving a fuzzy grain finish. The downcut offering is optimized for milling natural and engineered woods and helps prevent lifting on vacuum tables.

For more help on achieving a successful machining operation, or more information on Harvey Tool’s offering of End Mills for Wood, please contact Harvey Tool’s team of engineers at 800-645-5609.

Understanding Wood Properties for CNC Woodworking Projects

Machinists oftentimes confuse wood for being an “easy to machine material” during CNC Woodworking because of how much softer the material is than metal. In some sense this is true, as you can program wood cutting parameters in CNC Woodworking with much higher feed rates compared to that of most metals. On the other hand, however, wood has many unique properties that need to be accounted for in order to optimize the cutting process for maximum efficiency.

Types of Wood for CNC Woodworking

There are 3 main categories of wood for woodworking: hardwood, softwood and engineered wood.

Hardwood

The textbook definition of a hardwood tree is an angiosperm, more commonly referred to as a broadleaf tree. A few examples would be oak, birch, and maple trees. These types of trees are often used for making high quality furniture, decks, flooring, and construction components.

Softwood

A softwood is a coniferous tree, sometimes known as a gymnosperm. These are typically less dense than hardwoods and are therefore associated with being easier to machine. Do not let the name fool you: some soft woods are harder than some hardwoods. Harvey Tool’s Speeds and Feeds Charts for its offering of Material Specific End Mills for Wood are categorized by Janka hardness for this exact reason. Janka hardness is a modified hardness scale with a test specifically designed for classifying types of wood.

Softwood is used to make furniture, but can also be used for doors, window panes, and paper products. A couple of examples are pine and cedar trees. Table 1 lists 20 common woods with their Janka hardness.

Common Name:Janka Imperial Hardness:
Balsa90
Buckeye, Yellow350
Willow, Black360
Pine, Sugar380
Cottonwood, Eastern430
Chesnut, American540
Pine, Red560
Douglas-Fir, Interior North600
Birch, Gray760
Ash, Black850
Cedar, Eastern Red900
Cherry, American Black950
Walnut, Black1010
Beech, American1300
Oak, White1360
Maple, Sugar1450
Apple1730
Cherry, Brazilian2350
Olive2700
Rosewood, Indian3170
Table 1: Janka Hardness of Common Woods

Engineered Woods

Engineered wood, or composite wood, is any type of wood fiber, particle, or strand material held together with an adhesive or binding agent. Although some of these materials are easier to machine than solid woods, the adhesive holding the material together can be extremely abrasive. This can cause premature tool wear and create difficulties when cnc woodworking. It’s important to note that some types of engineered woods are more difficult to machine than others, specifically those with a higher amount of binding material. These types should be programmed with less aggressive speeds and feeds. For example, medium density fiberboard (MDF) if more difficult to machine than plywood, but much easier to machine than phenolic.

stack of medium density fiberboard pieces for cnc woodworking
Figure 1: Example of Medium Density Fiberboard

Properties of Wood

Grain Size

Technically speaking, wood can be considered a natural composite material as it consists of strong and flexible cellulose fibers held together by a stiffer glue-like matrix composed of lignin and hemicellulose. If you think in terms of construction, the cellulose fibers would be the steel rebar, and the concrete would be the lignin and hemicellulose. Wood with large cellulose fibers are considered to be coarse-grained (oak and ash). Woods that have smaller and fewer fibers are considered fine-grained (pine and maple). Softwoods tend to be fine-grained and are therefore stereotyped as being easier to machine since they do not have as many strong fibers to shear. It’s important to note that not all hardwood trees are coarse grained and not all softwood trees are fine-grained.

diagram of natural wood fibers for cnc woodworking
Figure 2: Simplified diagram of fibers that constitute natural wood. The cellulose fibers run vertically in this depiction.

Moisture Content (MC)

Moisture content (MC) is one of the most important variables to consider when machining wood. An extremely common problem with building anything with wood is its tendency to warp. Moisture variability in the air inevitably affects the moisture content within the wood. Any change in moisture content (whether an increase or a decrease) will disturb the shape of the workpiece. This is why one must take into account what type of moisture a product will be exposed to in its final resting place.

Equilibrium Moisture Content (EMC)

Equilibrium moisture content (EMC) occurs when wood has reached a balance point in its moisture content. Interior EMC values across the United States average at about 8%, with exterior values averaging around 12%. These values vary around the country due to the differences in temperature and humidity. For example, the southeastern United States have an average interior EMC of 11% while the southwest averages about 6% (excluding the coastal region). It’s important to consider what region and application the final product is going to encounter so that the wood with the correct moisture content can be selected before machining. Most species of flat-grain wood will change size 1% for every 4% change in MC. The direction of warping depends on the grain orientation.

United States map showing average regional indoor EMC
Figure 4: Average regional indoor EMC

Generally, power requirements for an operation rise with increasing moisture content, mainly because of the surge in density. Density of wood increases with rising MC. The additional power may be necessary to push a heavier chip out of the cutting zone during CNC Woodworking. It’s worth noting that, like synthetic polymers, wood is a viscoelastic material that absorbs energy as it becomes wetter. The proportional limit of its mechanical properties intensifies as MC increases.

When machining some types of wood, cutting region temperature will surge with increasing MC, but in other species it will decline. Be safe and avoid rapid tool wear by decreasing SFM when machining a wood with a moisture content above 10%. Harvey Tool Speeds and Feeds Charts suggest a decrease of 30 per MC percentage point. As always, though, it depends on the type of wood being machined and the type of operation being performed.

Temperature change is not the only reason higher moisture content is associated with rapid tool wear. Moisture within wood isn’t just associated with water, but also with resins, sugars, oils, starches, alkaloids, and tannin present within the water. These substances react particularly well with high speed steel, and to a lesser degree with carbide.

Knots and Their Effect on CNC Woodworking

A knot is a portion of a branch or limb that has become incorporated in the trunk of a tree. The influence of knots on the mechanical properties of wood is due to the interruption of continuity and change in direction of wood fibers associated with it. These properties are lower in this portion of the wood because the fibers around the knot are distorted and lead to stress concentrations. “Checking” (cracking due to shrinking) often occurs around knots during drying. Hardness and strength perpendicular to the grain are exceptions to generally lower mechanical properties. Because of these last two exceptions, woodworking machining parameters should be reduced when encountering a knotted portion of the workpiece to avoid shock loading.

typical natural wood knot in hardwood
Figure 5: Photo of a typical knot