The Lost Art of Mastery

There is value to honing and mastering a craft. But it takes time and experience.

by David Wynn

Director of Technical Services, PMPA

Published February 1, 2025

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I recently went down a rabbit hole watching various craftsman videos. Individuals carrying on traditions of long-lost trades. Things like Japanese long bows, wooden soup ladles, hand cut wooden shingles and hand-woven rope. All these steps take years to perfect. A person must dedicate large portions of their life mastering the techniques in every step of the process. From selecting the right raw material to final assembly, each area has multiple steps to learn. A person dedicates time and mental energy to learning how to recognize what is a conforming or non-conforming part. An intimate relationship between a person’s being and their craft develops. It becomes difficult to discern one from another. I think now about our current society. We live our life with a “drive through” mentality. It seems like we want it now. When I look at sports, I see a different story. Parents will tell their children to put in the time. Learn the basics and build up skills over time. Children are learning mastery of a craft. It is this attitude that we should bring to our work when we become adults.

We will spend between one-quarter and one-third of our life at work. We should pick a craft we love. Why do we feel we do not have to put years of work learning our way up through a company? Why do we feel entitled to start at the top at work? Why are we so offended when someone asks us to sweep the floor and wash parts? I remember when I started out that was all I got to do. Later, I was moved to secondaries, slowly moving my way up to setups. It was better this way. I learned every step of the process. I knew who the internal customers were. When I was washing parts, I did not want to receive a pan full of bar ends and chips. So as an operator, I kept that stuff out.

I think society has forgotten mastery of the craft. We no longer plan on three-to-five-year apprenticeships to build our knowledge for our career. There are pockets of this still — in the medical field, for instance. A surgeon must commit to a one-to-three-year fellowship after medical school, a time spent with a senior surgeon to hone your craft. It is a time of mastery, putting all that a doctor learned in school into practice.

As shop owners and managers — and as parents to the next generation — we must sell the importance of mastery better. We need to explain to the younger generation it is not demeaning to learn a craft. On the contrary, it is the ultimate job security. We have masters in our shops and they are valued. Most of the time, we keep them working part time after they retire. I was always told no matter what you do, do it at your best. If you are going to sweep the floor, then strive to be the best floor sweeper ever. We have a notion that certain types of work are demeaning. They are not! All tasks work together to make our shops run like well-oiled machines. Would you run your car without the oil? Pride in our work is essential to mastery. A level of never being satisfied.

The master is always striving to do it better the next time. Masters become masters not because of what they know, as much as it is that they know there is always more to learn.

To the next generation: Do not be afraid to take the path of mastery. Just like coming to a new team in freshman year, you must start at the bottom. Work your way to the top and prove yourself. Do whatever someone asks of you and do it well. Do not just do it well, do it best. If you want to find your way up a ladder, find the tasks no one wants to do and jump on those. Volunteer to do the tough work. Those who do what no one else does get noticed. You will also find that tough work teaches you lessons that will enhance your capabilities through your whole career. Put in time and effort and you will go far. We need you in this industry. The work pays very well and is rewarding, but the price for admission is your commitment. If you love it, then commit to it, and you will be rewarded with a distinguished career for which you will want to spend a third of your life.

 

Author

David Wynn is the PMPA Director of Technical Services with over 20 years of experience in the areas of manufacturing, quality, ownership, IT and economics. Email David

 

PMPA Craftsman Cribsheet #136: ISO Material Groups: Cast Iron

Published February 1, 2025

By David Wynn, Technical Services Manager, PMPA

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Cast irons are divided into three main grades for machining. Within those categories, they can be broken down into subgroups of ferritic and pearlitic cast iron. Ferritic cast irons are more ductile and have higher dimensional stability in higher temperatures. Pearlitic cast iron has a higher resistance to fretting corrosion. Fretting corrosion occurs in air when surfaces rub under oscillation, rotation or vibration under load. Pearlitic cast irons also have higher hardness and higher mechanical properties.

Some cast irons can be heat-treated to martensitic with higher hardness values. Hardness numbers in the chart are approximate ranges. Machinability varies widely in each category because cast irons of each type can vary widely in ductility and mechanical properties. The less ductile the material, the better the chip will break. There is little industry standard on the naming of the categories from insert manufacturers. Below approximates the categories and ranges.

Find the specific grade of cast iron in a reference manual to get surface feet per minute (sfm) with high strength steel (HSS). Multiply the HSS number by 2-2.5 and it will provide a reference point for what sfm you should use with carbide. The sfm guidelines given based on material groups above can vary widely, which can be seen in the machinability range.

 

 

 

 

Author

David Wynn

David Wynn, MBA, is the PMPA Technical Services Manager with over 20 years of experience in the areas of manufacturing, quality, ownership, IT and economics. Email: gro.apmp@nnywd — Website: pmpa.org.

What Does the Future Hold for Leaded Steels?

12L14 and other leaded steels are no longer melted in the U.S.

by Miles Free III

Director of Industry Affairs, PMPA

Published February 1, 2025

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My 50-plus-year career in steelmaking and manufacturing took me to employment at mills and meltshops in four different states, four different melt shops and authority over quality at 10 steel mills — both hot and cold finished. Leaded steel was a product of these plants.

In addition to the aforementioned plants, our cold finished mills often sourced leaded steel hot roll bars from Inland Steel or Bethlehem Steel. We cleaned, cold drew and straightened these bars, selling millions of pounds for hose fittings, carburetor and fuel line parts and many other automotive and non-automotive applications. Leaded steels provided machining shops with economies of production through increased tool life, increased speed, increased production rates and superior as-machined surface finish. Leaded steels were the optimum input for the screw machining industry in those days.

While leaded steels were often the most important product for our sales throughout the 1980s and 1990s, there were also enhanced grades: LedAX from Inland Steel and Beth Led B from Bethlehem Steel. Their higher price (mostly due to higher yield loss at the hot mill during rolling) could be justified when trying to hold difficult tolerances, finishes or cutting the finest threads. Despite the abundance of choices, the market was filled with rumors about the upcoming banning of lead, by customers, the Europeans or the EPA. A host of substitute materials — some containing bismuth, selenium, tellurium and even tin, were developed and brought to market. My counsel to our company’s customers — many of whom were PMPA multispindle screw machine shops making hose fittings for automotive and fluid power applications — was to not get too upset by all of these rumors. Leaded steels were plentiful in the market and would remain so despite all of the angst in the marketplace.

My final steel manufacturing employer, Republic, had two EPA permits to melt lead: one at Lorain, Ohio’s Basic Oxygen Furnace, and Continuous Caster (formerly U.S. Steel, where I was lab supervisor) and one at the Canton Electric Furnace Meltshop and Cast Roll (formerly Republic). I have been bullish on leaded steels as an appropriate and readily available input for our industry throughout my career.

Until the Lorain works (which had been integrated into the Bartech/ Republic Steel operations) were destroyed by a series of catastrophes starting with a cold weather fish-kill event. The fish clogged the cooling water intakes — crippling the blast furnaces. Without hot metal from the blast furnaces, there could be no steelmaking at the BOF/ Continuous Caster. An Electric Arc furnace was constructed to restore steelmaking at Lorain. A fire, just days before the scheduled start-up, made that construction a total loss. All steelmaking was destroyed at Lorain, which had one of the two valid EPA permits for melting leaded steel here in the U.S.

The Republic Canton Plant was owned by a Mexican firm, Grupo Simec. They shut down all of the Republic non- Mexican steel operations last summer when they moved all orders to their newer plant in Tlaxcala, Mexico (bit.ly/PMPA-PM0225a). The Republic Canton Meltshop had the second EPA permit for melting leaded steels.

All 12L14 and other leaded-grade special bar quality (SQB) bars that I know of in our shops are imported as hot rolled bars for cold drawing by U.S. or Canadian cold finishers from European sources — Germany and Great Britain being the primary countries of origin to my knowledge. There are supposed to be some changes in the British Steel Industry as they try to wean themselves off of Blast Furnace BOF production (Port Talbot) for “carbon/climate reasons,” which I expect could take the Brits out of the 12L14 game for more than a couple of years (bit.ly/PMPA-PM0225b).

Currently, the U.S. has tariffs imposed on steel bars coming in from overseas under Section 232. According to the U.S. International Trade Commission, the tariffs increased the average prices of steel and aluminum by 2.4% and 1.6%, respectively, disproportionately hurting “downstream” industries that use steel and aluminum in their production processes. Despite no domestic source of leaded steels, our imports of leaded steel are still covered by the tariff “to protect” domestic industry.

The re-election of Donald Trump has ensured that tariffs will be a major policy in the new administration. So now that we are forced to purchase leaded steels overseas, because there is no domestic melt source, we will be forced to pay even higher prices due to cost off shipping, current tariffs and expected new additional tariffs. If our domestic cold finishers can find leaded hot roll to cold draw for our shops.

So, I am no longer as bullish about the prospects for leaded steel availability in the United States. To the best of my knowledge, we have lost all domestic melt capacity for leaded steels. Great Britain is closing their leaded steel producing operations for at least a year. And importing leaded steel — regardless of supplier or country of origin — will result in much higher costs due to transportation, ongoing and increasing tariffs. We have yet to see how proposed Carbon Border Adjustments, or “Carbon Taxes,” will impact the market or availability.

If there was a hope, it would be that under the new administration, U.S. steelmakers might find an opportunity to apply for a permit to produce leaded steel bars for machining. Quite unlikely. So, I would advise all of us, as precision machining shops and purchasers of precision machined components, to start researching to develop process modifications and investigate available steel grades, new tools and coatings that we can adopt to deliver similar performance and economics as our traditional leaded steels continue to decline in availability and application, while increasing in price.

 

 

 

Author

Miles Free III is the PMPA Director of Industry Affairs with over 50 years of experience in the areas of manufacturing, quality and steelmaking. Miles’ podcast is at pmpa.org/podcast. Email Miles

 

Hiring A New Generation — Generation Z

Be prepared and understand what many don’t know about Gen Z.

by Veronica J. Durden

Events Coordinator, PMPA

Published February 1, 2025

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Most people are aware of the differences between workforce generations and the stereotypes that come with each. Generation Z is the newest generation entering the workforce, and they might be unlike anything you’ve seen before.

Perceptions Versus Reality
Online and social media often mock Gen Z for their fashion, speech, eating habits and sensitivities. However, they will be valuable assets to both the team and the company. This generation brings a fresh perspective and innovative ideas that can drive your company forward.

Preparing for Gen Z Employees

  • Loyalty: They may not automatically be loyal; companies will need to earn Gen Z’s loyalty by showing interest in their professional development. Building a strong relationship with Gen Z employees involves understanding their career goals and providing opportunities for growth and advancement.
  • Salary: According to Forbes, salary is a significant factor for Gen Z when choosing where to work. They are willing to sacrifice personal time to achieve financial stability, having witnessed the 2008 recession’s impact on families. Offering competitive salaries and benefits can attract and retain these employees.
  • Education and Experience: According to O.C. Tanner, members of Gen Z will have more degrees but less experience. They are eager to make a change and establish themselves in their organizations. They value growth and professional development and understand the importance of technology, potentially helping with social media. Providing mentorship and training programs can help bridge the experience gap and integrate them into the company culture.

Job Hopping
An important factor to remember is that job hopping is common among Generation Z. According to ResumeLab, 83% consider themselves job hoppers, leaving jobs for reasons like wages, company culture, work-life balance and meaningful job growth. This generation is not afraid to seek out new opportunities that better align with their values and career aspirations. Companies need to focus on creating a positive work environment and offering clear career progression paths to retain these employees.

Welcoming Gen Z
Generation Z will bring new perspectives to the workplace. Be open-minded and receptive to their ideas.

They seek not just a paycheck but a workplace with a culture that complements their lifestyle, such as flexible hours, environmental friendliness and diversity. Embracing these values can lead to a more dynamic and inclusive work environment. Ultimately, all generations share the same goals: stability, capability and the opportunity to flourish in an organization. Is your organization ready?

 

 

 

Author

Veronica Durden, MA, SHRM-CP is a human resources and workforce issues professional who specializes in manufacturing. Email: gro.apmp@nedrudv — Website: pmpa.org.

PMPA Craftsman Cribsheet #135:
ISO Material Groups: Stainless Steel

Published January 1, 2025

By David Wynn, Technical Services Manager, PMPA

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The letter “M” is for all stainless steels in the ISO material group categories. Most manufacturers break it down into three subgroups. I have made it into five subgroups because of the tendency to put martensitic, ferritic, and precipitation hardening stainless steel into the P ( steel) categories.
Stainless steels require sharp tools and low to no dwell times. Stainless steel especially in the higher nickel alloys work hardens readily. Spending too long in the cut or pushing too much with tools with low to no rake angle can cause work hardening.
The material listings are not exhaustive but examples of materials found in that sub-group to provide context of what materials fit into that group. 

*Machinability is a percentage of 1,212 (1,212 = 100%).

Find a grade-specific reference in a reference manual to get surface feet per minute (SFM) with high-speed steel (HSS). Multiply the HSS number by 2-2.5 and it will provide a reference point for what SFM you should use with the carbide. The SFM guidelines given based on material groups above can vary greatly, which can be seen in the machinability range.

 

 

 

 

Author

David Wynn

David Wynn, MBA, is the PMPA Technical Services Manager with over 20 years of experience in the areas of manufacturing, quality, ownership, IT and economics. Email: gro.apmp@nnywd — Website: pmpa.org.

STATE OF MANUFACTURING – Missouri Manufacturing

by Joe Jackson

Marketing & Events Assistant, PMPA

Published January 1, 2025

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Fabricated Metal Products Manufacturing is a subsector of manufacturing that makes critical goods from metal components.

Precision Turned Products Manufacturing is a subsector of fabricated metal product manufacturing that makes the components that MAKE IT WORK!

 

MISSOURI ECONOMIC OUTPUT

Missouri Manufacturing
NAICS 31-33
$39,920,000,000

Fabricated Metal Product Manufacturing
NAICS 332
$7,354,098,000

Precision Turned Product Manufacturing
NAICS 332721
$278,492,000

MISSOURI MANUFACTURING ACCOUNTS FOR

Manufacturing Is Productivity –12.05% of Missouri’s total output (GDP)

Manufacturing Builds Businesses –5,,093 manufacturing establishments in the state of Missouri.

Manufacturing Creates Jobs – 9.52% of all the Missouri employees are in the manufacturing sector. (274,000 employees)

Manufacturing produces for Missouri

  • Manufacturing is the 3rd largest GDP Producer in Missouri.
  • Manufacturing employment in Missouri has grown 5.6% since 2019, passing the national average of 1.8% over that time period.

Missouri is a great place for a career in manufacturing

  • Manufacturing jobs pay on average 29% over the average job in Missouri. (according to NAM.org)
  • Job sites are currently reporting in excess of 4,000 available manufacturing job openings in Missouri.

 

Sources: NAM.org, US Census, statista.com, IndustrySelect.com
Data selected to show relative values. May not be directly comparable due to differences in sampling, analysis, or date obtained.

 

 

 

 

Author

Joe Jackson

Marketing & Events Assistant, PMPA

Email: gro.apmp@noskcajj — Website: pmpa.org.

Urgency or Importance — Which Rules Your Day?

Poka-yoke your time — filter out the urgent so you can work on what is important.

by Miles Free III

Director of Industry Affairs, PMPA

Published January 1, 2025

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As a manager, as a supervisor, we are often driven by the “tyranny of the urgent.” Th at phone call that just came in, that rush order that “just has to get out,” or a host of other compelling things that insist “Get it done — now!” But is our obedience to the urgent even worth it? Perhaps as leaders, we need to recalibrate our reflexive obedience to the tyranny of the urgent, and instead invest in developing processes that make urgency a thing of the past.
One of the advantages of working at PMPA is that we get to collaborate with colleagues, members and truly talented, smart people. So, when this topic of urgency versus importance was brought up, I was pleased to hear PMPA’s Carli Kistler-Miller’s immediate impression: “You know, Miles, these are not mutually exclusive.” I can agree, the are not necessarily mutually exclusive, but I hope to show that when they are, we should not give our service to the urgent.
Urgency is characterized by two characteristics:
1) Urgency is time denominated. If urgent items are not completed by a certain time — a deadline (how telling) —then they cannot be completed at all. 2) Th e tasks are not necessarily thoughtful or cognitive work. In our everyday language we define urgency as “putting out fi res.” It is interesting to me that the word comes from the Latin “urgentum,” which means “to press hard, to urge.” We can see from this fact that urgency is generally delivering for single constituency or beneficiary. An urgent need is literally, a “pressing” one. Synonyms for urgency include emergency, critical and desperate. It is the time limit that raises the emotional stakes for urgency.
Urgency, upon reflection, is a short-term focus. By definition, if the urgent task is not completed by the deadline, it is a failure. We are all motivated, incentivized, coached and counseled to avoid failure. No wonder that urgency is such a powerful tyrant, and we its obedient servants.
Importance is different from urgent in that, while important work may have a deadline, the deadline itself is not an aspect of importance. Importance suggests great significance — especially to the greater organization and all of its stakeholders. Synonyms of importance, which can help us see its meaning more clearly include vital, necessary and crucial. Interestingly, the synonyms for importance do not suggest being time-bound. They do, however, suggest great value or meaningfulness.
So, why is it that we permit urgency to dictate importance in our work lives? Th e time deadline is an obvious answer because if we fail to complete the urgent task by the deadline, we cannot complete at all. But is there more? Henry Mintzberg cited a 1956 study by Robert Guest, “Of Time and Foremen,” in Harvard Business Review that established that 56 foremen averaged 583 activities per eight-hour shift, an average of one activity every 48 seconds. Mintzberg describes the work pace for chief executives as “unrelenting.” If our management is so tied up doing the urgent, who is doing the important?
If an urgent task is being completed every 48 seconds, when does the important work get done? (Note: Th is was in 1956, before cell phones and email. Do we really think that the demands have decreased in urgency? If anything, these new technologies have raised the bar and shortened the deadlines.)
Another study of 160 British middle and top managers found, according to Mintzberg, that they worked without interruption for a half-hour or more only about once every two days. Again, this was before internet, email and cell phones. Urgency, it seems, is a feature — not a bug — in managerial and supervisory work.
Our highest and best use, regardless of our organizational title in our shops, is to continuously improve our processes and performance. How much time is left in our eight- hour shift ( wink, wink, nudge, nudge) for continuous improvement? How much time is left for the other important, high-value work that is ours and ours alone, as leaders, managers and supervisors? How much quality time is the tyranny of the urgent stealing from us as loving parents, siblings and good friends?
It is my observation that things move from important to urgent when our systems and processes fail. But rather than address our system failures directly, we respond, like conditioned subjects in a psychology experiment, to respond to the urgent stimulus.
Quality is the absence of waste. When we focus on the merely urgent, allowing them to fill our day, we are stealing our highest and best work from our company, from our team and from our loved ones. Track the urgent issues that are stealing your attention and efforts from what is truly important. I am convinced that if we spent just 10% more time on the important, rather than the urgent, our shops would be even more productive, profitable and even happier places to work. It is time for a revolution to remove the tyrant of urgency in our lives.
Do not let the deadline of time bully you into spending your precious time doing the urgent, rather than the important. Time is the greatest waste as it is truly unrecoverable. Poka-yoke your time. Filter it by urgency
to target the processes needing improvement. Identify, improve, change or eliminate the processes that are creating needless urgency in your company. Celebrate the processes and the people that drive the processes and deliver the important work without urgency, hysterics or emotional blackmail.
Urgency gives us that psychology experiment reward
in the short term. But have we done the emotional and business multivariate calculus as to what it is truly costing us and our performers in the long run?
And as for whether urgency and importance are mutually exclusive, I will have to wait until my colleague Carli comes back from her well-earned vacation.

 

 

 

Author

Miles Free III is the PMPA Director of Industry Affairs with over 50 years of experience in the areas of manufacturing, quality and steelmaking. Miles’ podcast is at pmpa.org/podcast. Email Miles

 

Keeping It In The Family —
The Sixth Generation, Part 3

Seventeen-year-old Maya Bagshaw shares her perspective on the family business.

by Carli Kistler-Miller

Director of Programs & Marketing, PMPA

Published January 1, 2025

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In the last two articles, we heard from grown children who have taken over the family business and the parents who handed them the leadership baton. This month, we are going to get the perspective from a teenager who is looking to the future.

A Little Background
Aaron Bagshaw is the fifth-generation owner with his wife, Adria Bagshaw. Aaron and Adria own W.H. Bagshaw in Nashua, New Hampshire, which has been in business since 1870. (That is not a typo — the business has been around for 155 years.) W.H. Bagshaw is still the oldest pin maker in America, and it offers high-precision Swiss-style CNC turned parts.
Aaron and Adria did not assume that their 17-year-old daughter, Maya, would want to take over the business when they were ready to retire. Maya wasn’t the heiress-apparent and they didn’t push her. Even if her parents introduced Maya as the sixth-generation of owners, Maya thought, “Yeah, that’s what they say, but I’ll do something else.”

A Change in MIndset
Maya and I spoke at PMPA’s Annual Meeting 2024 in Dana Point, California.
Carli Kistler-Miller: You were thinking about doing something else. What was the “something else?”
Maya Bagshaw: When I was in middle school, I really wanted to be a teacher. I love babysitting and working with little kids, so being a teacher seemed like a good fi t. And then I wanted to own a bakery, or at least own my own business, but then Bagshaw will be my own business, so it’s OK, I realized.
C: What changed your mind about being the sixth-generation owner?
M: It was this February when we went to PMPA’s Management Update in Austin, Texas. My parents were introducing me as the sixth generation, the next CEO, and I got excited. I think I realized how many friends, opportunities, resources and experiences my parents have because of Bagshaw, and I love it. I wrote my college essay about my favorite smell — which is metal and oil — and I talk about growing up in the shop. And I realized, after seeing more of the business and starting to help my parents, that it was really interesting. I love walking around the shop with my parents and talking to everyone. It’s my favorite thing and I love working in the shop. Then I kept going to the PMPA conferences and meeting new people and it was really exciting. Hopefully, I get there.
C: What do you mean by “Hopefully, I get there?”
M: I can’t just assume that just because I’m their daughter that I will be the boss one day. I have to make sure that I take all the steps it takes to get there so that I can be the good leader that my parents are before I can take over. I’m looking at colleges and plan to major in business administration and I may minor in marketing. I have so much to learn, but I’m excited.

 

 

Author

Carli Kistler-Miller, MBA has over 25 years of experience with operations, event/meeting planning, marketing, writing and communications.
Email: gro.apmp@rellimc — Website: pmpa.org.

PMPA Craftsman Cribsheet #134:
ISO Material Groups: Steel

Published December 1, 2024

By David Wynn, Technical Services Manager, PMPA

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The letter “P” is for all steels in the ISO material group categories. Within that category there are subgroups. Most manufacturers break it into a range of four to seven categories. I find they are often broken down into five categories. Some manufacturers break it down as a range of machinability with P05 being the most free cutting to P40 being the most difficult. A few manufacturers who use seven groups include martensitic stainless steel as categories P5 and P6. I don’t like this in practice because I think stainless steel tends to be its own animal. Some manufacturers use a two number coding system rather than the single number seen below. The chart that will help you interpret where to find your material. The material listings are not exhaustive, but examples of materials found in that subgroup to provide understanding of what materials fit into that group. Find a grade-specific reference in a reference manual to get SFM with HSS. That will provide a reference point for what SFM you should use with the carbide. The SFM guidelines given based on material groups above can vary greatly, which can be seen in the machinability range. Machinability is calculated as a percentage of 1,212 (1,212 = 100%). 

 

 

 

 

Author

David Wynn

David Wynn, MBA, is the PMPA Technical Services Manager with over 20 years of experience in the areas of manufacturing, quality, ownership, IT and economics. Email: gro.apmp@nnywd — Website: pmpa.org.

The Power of the Coating

Diamonds are pure carbon, and they will weld to the carbon in the steel.

by David Wynn

Director of Technical Services, PMPA

Published December 1, 2024

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Tool coatings are everywhere. Coatings can be found for all sorts of applications. With all the choices out there, it becomes confusing which ones to choose. How do we know the right coating for our application? When we understand tool coatings, we unlock the potential of our machine tools.

Cold Welding
One of the first considerations when evaluating a tool coating for an application involves avoiding cold welding. Cold welding is the process where like materials under extreme pressure are bonded together. The atoms bond and it becomes a homogeneous mass. But why does cold welding matter for tool coatings? The reason is cutting forces in our machines are extreme. When using a tool coating that is similar or the same as the material we are cutting, the tool will weld to the material. This is why there are recommendations for avoiding certain coatings with certain materials.

Cold welding is the reason diamond-coated inserts are not good for steel.

Diamonds are pure carbon, and they will weld to bond with the carbon in the steel.

What do we need our coating to do? Is it to remove heat? To reduce friction? Do we need it to have edge strengthening properties for interrupted cuts? Does it need to help protect the tool from highly abrasive materials that contain aluminum oxides? There are coatings that offer high performance in multiple categories. All-purpose coatings work well in most general applications; however something like AlTiN is not recommended for use in aluminum alloys because of cold welding.

Heat Is the Enemy
The enemy of our tool coating is heat. Specific types of coatings can take distinct levels of heat before they start to degrade. It is important to know the factors that generate heat in the cutting tool. In physics, friction is where the heat is generated. In machining, we say speed causes heat, not feed. I know people are going to say they both cause heat. Both can, but speed puts heat into the tool whereas feed puts heat into the chip. We all know you can feed so hard you break a tool, but the fracture occurred due to forces flexing the tool, not overheating causing coating and edge failure.

Notes to coatings:

Max Working Temp. The temperature the coating will start to break down. You need to maintain cutting temperatures below this value to preserve the coating. Coolant and speed will play a significant role.

Vickers Hardness. The higher this value the more edge protection your tool will have. A higher value provides protection against abrasive inclusions in material. All data in this article is in Vickers Scale HV 0.05.

Coefficient of Friction. Friction is the enemy of our tool coating. Lower values of coefficient of friction allow us to achieve greater speed without coating wear. A lower value will also reduce flank wear because of less pressure when rubbing.

TiN. Titanium Nitride coating has been around a long time. It is that familiar gold color on tooling we have all seen and is still a solid coating for general purpose applications. It has a max working temperature of around 1,000 degrees F. TiN has a Vickers hardness of approximately 2,300 (varies by manufacturer). TiN has a coefficient of friction about 0.40.

AlTiN. Aluminum Titanium Nitride is a great all-around coating. It is a black to gray shiny coating. It has a max working temperature of around 1,400 degrees degrees F. AlTiN has a Vickers hardness of approximately 3,500 (varies by manufacturer). AlTiN has a coefficient of friction about 0.70.

TiB2. Titanium Diboride is great in non-ferrous materials. It is a dull gray-white coating. It has a max working temperature of around 900 degrees F. TiB2 has a Vickers hardness of approximately 2,800 (varies by manufacturer). TiB2 has a coefficient of friction about 0.35.

DLC. Diamond-like carbon (or amorphous diamond) is great in non-ferrous materials. It is a dull black coating. It has a max working temperature of around 750 degrees F. DLC has a Vickers hardness of approximately 8,200 (varies by manufacturer). DLC has a coefficient of friction about 0.1.

Tool coatings are changing all the time. Companies like PH Horn are producing new coatings and reinventing old ones. Experiment with different companies’ coatings within the same families. For instance, one company’s AlTiN may be better than another for your current application. Within the standard families of coatings, there are hundreds of proprietary coatings offered. Stay up to date with your technical sales reps to get coatings that will work best in your application. Having a great relationship with your tech rep will go a long way to getting your job done as efficiently as possible. Here’s to more chips in the hopper and more parts in the pan!

 

Author

David Wynn is the PMPA Director of Technical Services with over 20 years of experience in the areas of manufacturing, quality, ownership, IT and economics. Email David