January 2022

The art of metal casting — melting metal, pouring it into molds, and shaping it into usable forms — is as old as civilization itself. Archeologists have uncovered metal casting relics from as early as 300 BC, possibly even older, depending on who you ask.

Most of the oldest artifacts come from Mesopotamia, where early craftspeople used clay molds and fire pits to cast copper, gold, and silver. It was here that the first alloy — bronze, a mix of copper and tin — was born. That single innovation sparked a new era of metal tools, weapons, and technology.

But like every great invention, metal casting has evolved. And the reasons are as much about human progress as they are about science.

Why Metal Casting Changed Over Time

Two major shifts drove the evolution of foundries:

Humans stopped migrating and started settling, giving rise to cities, economies, and steady production
Mining technology improved, giving us access to more raw material in less time

The result? Foundries got bigger, smarter, and more influential — shaping everything from warfare to water systems.

Foundry Highlights from the 19th Century

By the 1800s, metal casting was more than craft. It was an industry. The 19th century brought several major advancements:

Open-hearth furnaces for higher-quality steel
Sandblasting to clean castings faster and more effectively
Gear-tilted ladles to pour molten metal more safely

This era helped drive the industrialization of the United States, with foundries fueling the construction of railroad tracks, ironclad warships, and even America’s first submarine, launched in 1881.

Breakthroughs in the 20th Century

The 1900s ushered in a wave of innovation:

The coreless electric induction furnace changed how we melt metal
Low-carbon stainless steel opened up new use cases
Foundries began serving defense, aerospace, HVAC, and automotive sectors

This century saw foundries expand rapidly across North America. They became central to U.S. manufacturing.

Fun Fact:
The American Foundry Society (AFS) first met in 1896, but its first student chapter wasn’t launched until 1907 — in Minnesota. That same year, a patent was issued for high-pressure die casting machinery, a technology still used today.

The Foundry Industry Today

Metal casting remains a cornerstone of manufacturing — just more advanced than ever.

Today, the U.S. foundry industry is worth over $33 billion, with close to 1,900 active foundries and nearly 200,000 workers. Metal castings are found in 90% of durable goods, from clean water systems and farm equipment to energy infrastructure and transportation components.

And the modern foundry? It’s high-tech.

Many now use:

CAD software for design
3D printing for mold creation
Robotics and automation for efficiency
Casting analysis to improve quality and reduce waste

Foundries have never been more precise — or more important.

See It for Yourself

Want a closer look? Revisit our article on how steel is made and check out this factory tour of the St. Paul Foundry. You’ll see molten metal in action and the incredible technology that brings modern castings to life.

After that, look around. From the water pipes beneath your feet to the machine parts running your factory — metal castings are everywhere.

The National Institute for Occupational Safety & Health (NIOSH) defines Personal Protective Equipment (PPE) as the last line of defense in preventing workplace injuries, illnesses, and fatalities.

That means PPE doesn’t replace smart design or safer processes — but when a hazard slips through the cracks, PPE protects the individual. It can be the difference between a close call and a serious injury.

Here at FlexTrades, we believe safety starts with knowledge. So we’ve put together a quick breakdown of essential PPE and how to use it.

The Four Basic Categories of PPE

While each job site is different, PPE typically falls into one of four categories:

Face and Eye Protection
Respiratory Protection
Skin and Body Protection
Hearing Protection

A hazard assessment will help you determine which equipment is necessary. Below, we break down each category and offer practical tips to help you get it right.

Face and Eye Protection

This type of PPE shields you from sprays, splashes, flying objects, and high-heat tasks like welding.

Common examples include:

Goggles
Safety glasses
Face shields
Welding visors

Pro Tip: Always make sure your eyewear meets ANSI Z87.1 standards. Inspect lenses regularly for cracks or wear.

Respiratory Protection

Respiratory PPE is essential when you’re exposed to dust, fumes, gases, or biological hazards. It protects your lungs, airways, and internal organs.

Examples include:

Full-face respirators
Self-contained breathing apparatus (SCBA)
Gas masks
N95 masks and surgical masks

Pro Tip: Always fit test respirators and replace filters regularly to maintain effectiveness.

Skin and Body Protection

This category is broad — it includes anything designed to protect your skin or body from burns, cuts, impact, chemical exposure, or falls.

Key areas of protection:

Head – Hard hats, bump caps
Body – Safety vests, flame-resistant suits
Hands – Cut-resistant gloves, heat shields
Feet – Steel-toe boots, anti-slip soles
Fall – Harnesses, lanyards, and anchor points

Pro Tip: If gear is damaged or contaminated, replace it immediately. Compromised PPE isn’t PPE at all.

Hearing Protection

Loud environments can lead to long-term hearing damage if proper protection isn’t used.

Options include:

Earmuffs
Earplugs
Ear caps

Pro Tip: Hearing protection is only effective if it fits properly. Dirty or worn equipment should always be discarded.

Your PPE Checklist Starts Here

If you’re not sure where to begin, use this guide as a PPE checklist to support your next hazard assessment. Improving your understanding of safety gear is a simple but powerful way to strengthen your facility’s safety culture.

Want to go further? Revisit our Every Technician’s Toolbox blog to learn more about PPE and other essential safety practices.

And if you already know your way around all this gear, you might be ready for your next opportunity in manufacturing. Send your resume to retoolrecruiting@flextrades.com and let’s see where you belong.

At FlexTrades, we believe in supporting American manufacturing from every angle — not just by providing workforce solutions, but by advocating for the skilled trades and the technical education that fuels them.

That’s why we’re kicking off this year’s Monthly Manufacturing Calendar Highlight with a reminder: CTE Month® begins February 1st.

This is your chance to celebrate, support, and elevate the future of the skilled trades. Let’s talk about what CTE Month is and how you can get involved.

What Is CTE Month?

Career and Technical Education (CTE) helps students of all ages prepare for high-wage, high-demand careers. And we’re not just talking about students in high school — adult learners, returning workers, and veterans are part of the movement, too.

CTE Month happens every February as a nationwide campaign to:

Raise awareness about CTE’s role in workforce development
Celebrate CTE programs and their achievements
Encourage partnerships between educators, employers, and policymakers

You may have even seen it featured during events like the Super Bowl — like this commercial from Oklahoma Career Tech.

How Can You Celebrate CTE Month?

Whether you’re an educator, employer, or just someone who believes in the power of skilled trades, there are plenty of ways to get involved:

Instructors / Educators: Host a tour or open house. Let the community see what CTE looks like up close.
Businesses / Employers: Partner with local schools or host a job fair. Share success stories about CTE graduates on your team.
Graduates / Technicians: Speak up. Share your story publicly. The Skills Gap grows wider when people don’t understand the value of your experience.
Everyone Else: Download a CTE Month Zoom background and use it during virtual meetings to show your support — no speech required.
No matter your role, there’s a way to advocate for CTE this month. Sometimes, all it takes is showing up and being visible.

What’s Next?

February is just the start. Manufacturing advocacy doesn’t stop with CTE Month. In fact, October and MFG Day will be here before you know it.

So get involved. Be loud. Share your story. Support the people and programs building the future of American manufacturing.

And if you know of an industry event worth highlighting, email our Writing Team — we’d love to feature it in the months ahead.

Manufacturing sits at the intersection of science, technology, engineering, and math. It’s where ideas become tangible and precision meets production. But behind the machinery and the measurements is a set of principles that most of us first encountered in a middle school science class.

So today, let’s talk about something that sounds simple but plays a massive role in manufacturing: static electricity.

What Is an Atom, and Why Does It Matter?

To understand static electricity, we have to go all the way down to the atomic level.

Everything you can touch, build, or break is made of atoms. These atoms are made up of particles — protons, electrons, and neutrons — centered around a nucleus. Here’s the shorthand:

Protons have a positive charge
Electrons have a negative charge
Neutrons are, as the name suggests, neutral

In most materials, the number of protons and electrons is equal, so the object carries no electrical charge. But rub two materials together — especially ones with different conductive properties — and you disrupt that balance. Electrons jump from one surface to another, leaving one object more negative and the other more positive.

That imbalance? That’s static electricity.

Want to dig deeper into atomic structure? Start here.

Conductors vs. Insulators

Not all materials behave the same. Some let electrons move freely. Others don’t.

Conductors (like water and metal) have loosely bound electrons, making them ideal for electron transfer
Insulators (like rubber and plastic) hold electrons tightly, limiting their movement

This difference is critical in understanding how static electricity forms — and how it affects real-world environments.

The Balloon & Hair Trick

It’s a classic. You rub a balloon on your head and your hair starts to rise. But why?

Rubber is an insulator, so it doesn’t let electrons move easily across its surface. Hair, on the other hand, acts more like a conductor. When you rub the balloon on your head, electrons from your hair transfer to the balloon. The balloon now has more electrons (and becomes negatively charged), while your hair has fewer electrons (becoming relatively positive).

That difference in charge is static electricity. And it’s strong enough to pull your hair toward the balloon.

Fun? Sure. But in a manufacturing setting, it’s a different story.

Static Electricity in Manufacturing

Static electricity can be dangerous in a production environment. It’s not just an annoying zap. It’s a legitimate safety and quality risk.

Electrostatic discharge (ESD) — that tiny shock you sometimes feel when touching a doorknob — can do real damage. In manufacturing, ESD can:

Ignite flammable gases or vapors
Destroy sensitive electronic components
Attract dust and particles in cleanrooms
Cause materials to stick together or misalign

That’s why manufacturers go to great lengths to manage it.

How Manufacturers Manage Static Electricity

To minimize the risks of ESD, many facilities use specialized tools and processes, including:

ESD-safe clothing to reduce charge buildup
Antistatic wrist straps and grounding bracelets to safely redirect charges
ESD mats to neutralize static underfoot
Zero-charge hand lotions and cleaners to reduce friction on skin
Controlled humidity to reduce airborne electron movement

In highly controlled environments — especially in electronics manufacturing — these precautions aren’t optional. They’re essential.

Want to Learn More?

FlexTrades has a growing library of How It’s Made content that explores the science behind the trades. Check out more on our blog and see what else goes into the work behind the work.

What’s the craziest thing you’ve ever done? What about the most charitable?

At FlexTrades, we like to answer both questions with one story — the Polar Plunge.

If you’re not familiar, the Polar Plunge is a national fundraising event where brave souls jump into icy water in support of Special Olympics. It’s cold. It’s intense. And it’s one of the most rewarding things we do all year.

In Minnesota alone — where, by the way, we have 14,000+ lakes, not just the 10,000 you’ve heard about — this event is a big deal. Every winter, people cut holes in thick sheets of lake ice and dive in. For a cause. For the community. And for the joy of doing something that matters.

About the Special Olympics

The Special Olympics started small. In 1962, Eunice Kennedy Shriver hosted the first “Camp Shriver” in the backyard of her Maryland home. She wanted kids with intellectual disabilities to have a place to play, grow, and belong — because, at that time, they were often excluded from mainstream programs.

That first camp became an annual tradition, then a movement. On July 20, 1968, more than a thousand athletes from the U.S. and Canada came together in Chicago for the first International Special Olympics Summer Games.

Today, that same movement spans over 170 countries and reaches more than 5 million athletes worldwide. And it all started with one idea: everyone deserves a chance to compete.

My Personal Why

My support for Special Olympics didn’t begin with a plunge. It began with my cousin, Joey.

Joey was born with Down syndrome in 1960, during a time when children with special needs were often institutionalized and separated from their families. His parents were part of a generation that pushed back — advocating for inclusion before it had a name. And they found community and opportunity through Special Olympics.

By the time I was born, Joey was already competing regularly. Over his lifetime, he took part in more than two dozen Minnesota state games and a handful of national events. The skills, pride, and friendships he gained from competition changed his life — and the lives of those around him.

When I started my career at FlexTrades in 2017, I knew I wanted to support that mission more actively. That’s when I joined my first Polar Plunge.

FlexTrades Supports the Special Olympics

The experience was everything I’d hoped for and more — fun, moving, energizing. I couldn’t stop talking about it. And by the following year, several coworkers joined me.

That was the start of our official FlexTrades Plunge Team.

Since then, we’ve raised more than $14,000 for Special Olympics Minnesota. To put that in perspective: just $500 is enough to launch a new delegation in the state. It’s proof that a little support can go a long way.

Support Our 2022 Polar Plunge

Our fifth plunge took place on February 19, 2022, in Prior Lake, Minnesota. Even if you weren’t in the state — or willing to jump in yourself — there were still plenty of ways to get involved.

Plunge virtually — or toss something silly into the lake in your place (rubber chicken, anyone?)
Donate — support the FlexTrades team directly
Show up — spectators are always welcome and encouraged
Share your support — a few kind words on social media go a long way

And if you’re feeling inspired, you can start a plunge of your own no matter where you live.

Let’s Keep It Going

If you have questions about Special Olympics, the Polar Plunge, or how FlexTrades supports the cause, reach out to us at writingteam@flextrades.com.

And remember the athlete’s oath that has guided Special Olympics for decades:

“Let me win. But if I cannot win, let me be brave in the attempt.”