The Propeller That Doesn't Need to Be There
On making beautiful things when no one asks you to
The lower bearing support on the Mikros One is shaped like a four-bladed propeller. Officially, it's part number MK356. Unofficially, it's a memorial to a Spitfire, a squadron, and the collision of engineering necessity with personal history.
What My Father Taught Me
My father could build machines without drawings. Just a mental model, raw materials, and his lathe. He taught me this from age three, how to see the finished thing before it exists, how to work metal until it matches what's in your head.
But he also taught me something else: useful things should be beautiful.
He'd spend hours adding chamfers no one would see, polishing surfaces that would never be touched, shaping components into forms that worked no better than simple cylinders, but looked right. It took longer. Cost more. Wasn't "necessary" by any rational measure.
I asked him once why he bothered. He said, "Because you'll use this tool for twenty years. Every time you pick it up, it should remind you that someone cared."
That shaped everything I've done since.
A Life Around Aircraft
I fell in love with engineering early, tanks, ships, firearms, aircraft. Anything mechanical. But aircraft especially.
At thirteen, I joined the Air Cadets, 92 Squadron. At nineteen, I joined the army as an aircraft maintenance engineer.
You learn things when you maintain aircraft that you don't learn from books: how parts fail under stress, which engineering decisions were brilliant and which were compromises, that the best-engineered machines have a certain rightness to them, form that serves function perfectly.
And you learn to spot the difference between engineers who did the minimum and engineers who cared.
The Rolls-Royce Standard
Rolls-Royce became my benchmark for what engineering should be.
Their Merlin engines, the ones that powered Spitfires and Hurricanes, had hand-polished internal surfaces. Not because it improved performance measurably. Because excellence includes details no one asked for.
The engineers who designed those engines could have made them work just fine with rougher finishes. They chose not to. They chose to make something that was beautiful even in the parts you'd never see. Undoubtedly driven by honouring Sir Henry Royce, a man whose passion mirrored my fathers.
That philosophy, function first, but beauty always, became my standard too.
When Necessity Meets Memory
The first design used three blades. It looked right, but testing revealed insufficient torsional stiffness under grinding loads. We needed more material, better geometry.
Four blades solved it. The additional spoke increased rigidity without adding significant mass. Engineering necessity, nothing more.
Then I realized what I'd drawn.
The Mk9 Spitfire has a four-bladed propeller. The BBMF (Battle of Britain Memorial Flight) operated MK356, a Mk9 painted in 92 Squadron colours, my squadron. It crashed in 2024. Gone.
The Mikros One is our Mk9 model. Fourth-generation design, ninth iteration of the grinder concept. I'd been calling it the Mk9 for months before I made the bearing support four-bladed.
I didn't plan this. The engineering required four blades. History provided the rest.
I named the part MK356.
Why It Matters
Most brands invent heritage. They construct narratives about craftsmanship traditions they have no connection to, or engineering lineages they've never practiced.
This propeller wasn't invented for marketing. It exists because:
- We needed stiffness (engineering)
- I refused to make it purely utilitarian (craft)
- The form that solved the engineering problem happened to connect to a squadron, an aircraft, and a memorial (serendipity)
You can't manufacture that kind of alignment. You can only recognize it when it happens and choose to honour it.
The Honest Engineering Position
Here's what the four-bladed geometry actually does:
Functionally: Increases torsional rigidity by adding material at optimal radial distance from the centre axis. The four-spoke configuration also provides better finger purchase during assembly and disassembly, natural grip points for technicians.
Aesthetically: It looks like a Mk9 Spitfire propeller because it has the same blade count. That wasn't the design goal, but it became meaningful once I realized the connection.
We won't claim the propeller shape is purely aesthetic if it serves function. And we won't invent performance benefits if the real reason is memorial. Both are true. Engineering and memory, intersecting in a part number.
Heritage as Differentiator
Our heritage isn't invented: a father who taught precision machining to a three-year-old. Decades maintaining military aircraft. 92 Squadron. A lifetime studying engineering that prioritizes beauty alongside function. An allergy to bullshit inherited from a man who'd rather spend an extra day making something right than ship something mediocre on time.
That heritage shows up in odd places. Silicon carbide bearings with asymmetric ball counts. Vernier scales on hand grinders. A bearing support numbered MK356, shaped like the propeller from a Spitfire that's gone, from a squadron I served in, on a grinder model that carries the same mark designation.
We make things the way my father taught me: as well as we can, because anything less feels wrong.
The Bottom Line
Part number MK356 makes the grinder work better, four blades provide the stiffness three couldn't deliver. But it also makes it ours in a way circular bearings never could.
If you're the kind of person who appreciates when engineering necessity aligns with personal history, if you understand why Rolls-Royce polished parts no one would see, or why a part number can be a memorial, then you'll understand why this matters.
If you think it's sentimental? We're probably not your brand anyway.
We're building tools for people who care about the same things we do: precision, honesty, craft, and the belief that sometimes engineering gives you exactly the form you need for reasons you didn't plan.
The propeller stays. Four blades. MK356.
