Atelier Durdan
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Sorry for the late reply,
yes, this version is available for all our razor heads.
Atelier DURDAN News
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yes, this version is available for all our razor heads.
Atelier Durdan
Forum GOD!
Hi everyone,
I've spent the past few months writing what I hope will be a useful reference article on safety razor geometry. I wanted to share the core ideas here, because I think there's a widespread misunderstanding in our community about what makes a razor shave the way it does — and it starts with how we talk about blade gap.
The problem with gap-only thinking
When we discuss razors, the conversation almost always comes down to the gap number. "0.70 mm, it's mild." "1.20 mm, it's aggressive." We've all been there. But when I design a razor head in CAD, the gap is just one of four geometric parameters I work with — and honestly, it's not the most important one.
Two razors can have the exact same gap and shave completely differently. I've seen this in my own designs, and I think most experienced shavers have felt it too without necessarily having the vocabulary to explain why.
Here's the framework I use. Every razor head is defined by four parameters:
1. Cutting angle — the angle at which the blade meets the skin relative to the shave plane (the line between cap and baseplate contact points). This is the first thing I set when I design a razor. A narrower angle penetrates more easily — efficient, but less forgiving. A wider angle skims the surface — safer, but can scrape instead of cut. My razors generally sit above 30°. Below 25° gets dangerous on most geometries. Above 35°, cutting quality drops.
This is the parameter almost nobody talks about, yet it's foundational. Take two razors identical in gap, span, and exposure — change only the cutting angle, and the narrower one will feel noticeably more aggressive.
2. Blade gap — the vertical distance between the blade edge and the baseplate at its closest point. Yes, it matters. But it only measures a height at one point. It tells you nothing about the shape of the baseplate beyond that point — and that shape is what determines how the skin actually deforms during the shave.
3. Guard span — this is the one I wish more people knew about. The span is the distance between the blade's cutting edge and the point where the baseplate contacts the skin — measured along the skin surface, not vertically. It's the length of "free" skin that can deform unsupported.
Why does it matter so much? Because the wider the span, the more skin can bulge toward the blade, and the more efficiently the hair is presented to the edge. There's also a pressure effect: more free skin pushing against the blade means more cutting pressure. It's the span, not the gap, that determines how efficiently a razor actually cuts.
A concrete example: La Faulx with the Classique baseplate has a gap of 0.56 mm. Sounds mild, right? But the span is 2.67 mm — a span-to-gap ratio of nearly 5:1. The baseplate extends far outward, creating a wide skin deformation zone. That's why La Faulx in Classique is surprisingly efficient for its gap number. The span is doing the work.
4. Blade exposure — the position of the blade edge relative to the shave plane. Positive = the blade protrudes beyond the line between cap and baseplate (more direct, more blade feel). Negative = the blade sits behind that line (milder, skin has to "reach" the blade). This is the comfort dial — but it's also an efficiency lever, because more exposure means more blade pressure on the hair.
An often-overlooked factor here: skin firmness. Supple skin deforms easily and reaches the blade even with negative exposure. Firm skin may not deform enough — and the razor feels like it doesn't cut, not because of a design flaw, but because the geometry doesn't match that skin type.
How they interact
None of these works alone. The cutting angle sets the safety framework. The span drives real-world efficiency. Exposure sets comfort and contributes to closeness. And the gap is a visible consequence of the head geometry — correlated with span, but not a replacement for it.
That's why on Le Maurice, I keep exposure fixed at +0.05 mm across all baseplates (0.80 to 2.00 gap). The efficiency increase comes entirely from the growing span — not from making the blade more exposed. Efficiency up, aggressiveness constant. That's the whole concept.
And it's why the Vestige can have a 0.19 mm gap and still shave effectively — the span is created laterally through arch-shaped openings in the baseplate, not in the conventional cross-section direction.
The full article
I've written all of this up in much more detail — with technical diagrams, measurement methodology (CAD + microscope verification with a precision dowel pin), data for each razor in the range, and a practical guide by user profile.
The article is available in English and French on our blog: here
Happy to answer any questions about razor geometry, my design process, or how I approach the balance between these parameters. This is the stuff I think about every day at the workshop — and I genuinely enjoy discussing it.
Augustin
I've spent the past few months writing what I hope will be a useful reference article on safety razor geometry. I wanted to share the core ideas here, because I think there's a widespread misunderstanding in our community about what makes a razor shave the way it does — and it starts with how we talk about blade gap.
The problem with gap-only thinking
When we discuss razors, the conversation almost always comes down to the gap number. "0.70 mm, it's mild." "1.20 mm, it's aggressive." We've all been there. But when I design a razor head in CAD, the gap is just one of four geometric parameters I work with — and honestly, it's not the most important one.
Two razors can have the exact same gap and shave completely differently. I've seen this in my own designs, and I think most experienced shavers have felt it too without necessarily having the vocabulary to explain why.
Here's the framework I use. Every razor head is defined by four parameters:
1. Cutting angle — the angle at which the blade meets the skin relative to the shave plane (the line between cap and baseplate contact points). This is the first thing I set when I design a razor. A narrower angle penetrates more easily — efficient, but less forgiving. A wider angle skims the surface — safer, but can scrape instead of cut. My razors generally sit above 30°. Below 25° gets dangerous on most geometries. Above 35°, cutting quality drops.
This is the parameter almost nobody talks about, yet it's foundational. Take two razors identical in gap, span, and exposure — change only the cutting angle, and the narrower one will feel noticeably more aggressive.
2. Blade gap — the vertical distance between the blade edge and the baseplate at its closest point. Yes, it matters. But it only measures a height at one point. It tells you nothing about the shape of the baseplate beyond that point — and that shape is what determines how the skin actually deforms during the shave.
3. Guard span — this is the one I wish more people knew about. The span is the distance between the blade's cutting edge and the point where the baseplate contacts the skin — measured along the skin surface, not vertically. It's the length of "free" skin that can deform unsupported.
Why does it matter so much? Because the wider the span, the more skin can bulge toward the blade, and the more efficiently the hair is presented to the edge. There's also a pressure effect: more free skin pushing against the blade means more cutting pressure. It's the span, not the gap, that determines how efficiently a razor actually cuts.
A concrete example: La Faulx with the Classique baseplate has a gap of 0.56 mm. Sounds mild, right? But the span is 2.67 mm — a span-to-gap ratio of nearly 5:1. The baseplate extends far outward, creating a wide skin deformation zone. That's why La Faulx in Classique is surprisingly efficient for its gap number. The span is doing the work.
4. Blade exposure — the position of the blade edge relative to the shave plane. Positive = the blade protrudes beyond the line between cap and baseplate (more direct, more blade feel). Negative = the blade sits behind that line (milder, skin has to "reach" the blade). This is the comfort dial — but it's also an efficiency lever, because more exposure means more blade pressure on the hair.
An often-overlooked factor here: skin firmness. Supple skin deforms easily and reaches the blade even with negative exposure. Firm skin may not deform enough — and the razor feels like it doesn't cut, not because of a design flaw, but because the geometry doesn't match that skin type.
How they interact
None of these works alone. The cutting angle sets the safety framework. The span drives real-world efficiency. Exposure sets comfort and contributes to closeness. And the gap is a visible consequence of the head geometry — correlated with span, but not a replacement for it.
That's why on Le Maurice, I keep exposure fixed at +0.05 mm across all baseplates (0.80 to 2.00 gap). The efficiency increase comes entirely from the growing span — not from making the blade more exposed. Efficiency up, aggressiveness constant. That's the whole concept.
And it's why the Vestige can have a 0.19 mm gap and still shave effectively — the span is created laterally through arch-shaped openings in the baseplate, not in the conventional cross-section direction.
The full article
I've written all of this up in much more detail — with technical diagrams, measurement methodology (CAD + microscope verification with a precision dowel pin), data for each razor in the range, and a practical guide by user profile.
The article is available in English and French on our blog: here
Happy to answer any questions about razor geometry, my design process, or how I approach the balance between these parameters. This is the stuff I think about every day at the workshop — and I genuinely enjoy discussing it.
Augustin
Johnny Bravo
Forum GOD!
Thanks for the post, I really enjoyed reading this and learning something new.
Atelier Durdan
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thank you for your feedback
Atelier Durdan
Forum GOD!
Hi all,
For those of you who follow our work here, I wanted to share an update directly with you before it goes wider. It concerns how the workshop is going to operate from 2026 onwards, and there are a couple of things some of you will want to act on.
The short version
We're tightening the permanent catalogue and moving customisation into two dedicated windows per year. The reasons are straightforward: the workshop is two people, our production capacity is deliberately modest, and we've reached a point where the breadth of options on offer leaves no room for designing new things or improving what already exists. Le Maurice alone has 672 possible configurations. The premium polish takes a full day per piece on titanium. Add wooden handles, leather sleeves, custom boxes — and the workshop has spent the past year configuring, finishing, shipping, repeating. Not bad work. Just not what I started this for.
So we're changing course.
What stays available year-round
Four razors, each in their most-sold configuration:
On La Faulx, the Numéro 7 and the Horizon, we're stepping back from bronze, copper and the premium polish on a daily basis. These are the time-eaters that derail the rest of production. The technical range stays intact (gaps, adjustability) — what concentrates is materials and premium finishes.
The customisation windows
Twice a year, for one week each. Everything comes back: bronze, copper, premium polish, medieval finish, leather sleeves, wooden boxes, all variants of every model.
Process: dedicated form during the window → personalised quote → production at usual lead times. No more direct online ordering for custom configurations.
Le Vestige — discontinued
This is the part some of you may want to act on. The Vestige is being discontinued. It never really found its place in our sales, it's mechanically more delicate to produce than the others, and the workshop space it took up is going to other things. Production stops, the plates won't be remade.
The current customisation period — open until 11 May 2026 — is the last opportunity to order one. After that date, the Vestige won't be available to order, and it won't return during the customisation windows either.
For owners of an existing Vestige: please contact me directly at [contact email] for any specific need — I'll handle individual cases as best I can on a one-by-one basis.
A new project
There's something new in development that I won't go into in detail yet — something the workshop has never done before. Prototype exists, it's coming along well. A big part of why this restructuring is happening now is precisely to make room for it. More on that in the coming weeks.
I'm around for any questions — happy to answer them here directly.
Thanks to those of you who have shared feedback on our work over the years — it matters more than you probably think.
Augustin
For those of you who follow our work here, I wanted to share an update directly with you before it goes wider. It concerns how the workshop is going to operate from 2026 onwards, and there are a couple of things some of you will want to act on.
The short version
We're tightening the permanent catalogue and moving customisation into two dedicated windows per year. The reasons are straightforward: the workshop is two people, our production capacity is deliberately modest, and we've reached a point where the breadth of options on offer leaves no room for designing new things or improving what already exists. Le Maurice alone has 672 possible configurations. The premium polish takes a full day per piece on titanium. Add wooden handles, leather sleeves, custom boxes — and the workshop has spent the past year configuring, finishing, shipping, repeating. Not bad work. Just not what I started this for.
So we're changing course.
What stays available year-round
Four razors, each in their most-sold configuration:
- La Faulx — all gaps available
- Numéro 7 — all gaps available
- Horizon — adjustable, naturally
- Le Maurice — single version: 1.0, raw-machined stainless steel, smooth comb
On La Faulx, the Numéro 7 and the Horizon, we're stepping back from bronze, copper and the premium polish on a daily basis. These are the time-eaters that derail the rest of production. The technical range stays intact (gaps, adjustability) — what concentrates is materials and premium finishes.
The customisation windows
Twice a year, for one week each. Everything comes back: bronze, copper, premium polish, medieval finish, leather sleeves, wooden boxes, all variants of every model.
Process: dedicated form during the window → personalised quote → production at usual lead times. No more direct online ordering for custom configurations.
- First window 2026: 14–20 September
- Second window: early 2027 (date TBC)
Le Vestige — discontinued
This is the part some of you may want to act on. The Vestige is being discontinued. It never really found its place in our sales, it's mechanically more delicate to produce than the others, and the workshop space it took up is going to other things. Production stops, the plates won't be remade.
The current customisation period — open until 11 May 2026 — is the last opportunity to order one. After that date, the Vestige won't be available to order, and it won't return during the customisation windows either.
For owners of an existing Vestige: please contact me directly at [contact email] for any specific need — I'll handle individual cases as best I can on a one-by-one basis.
A new project
There's something new in development that I won't go into in detail yet — something the workshop has never done before. Prototype exists, it's coming along well. A big part of why this restructuring is happening now is precisely to make room for it. More on that in the coming weeks.
I'm around for any questions — happy to answer them here directly.
Thanks to those of you who have shared feedback on our work over the years — it matters more than you probably think.
Augustin