The 5 Rules of Good Cookware - Heritage Steel

30 Jun.,2025

 

The 5 Rules of Good Cookware - Heritage Steel

Defining the ideal cookware

We generally want two basic properties in a utensil. Its surface should be chemically unreactive so that it won’t change the taste or edibility of food. And it should conduct heat evenly and efficiently, so that local hot spots won’t develop and burn the contents... [Multiclad stainless steel] hybrids are the closest thing we have to the ideal chemically inert but thermally responsive pan

If you are looking for more details, kindly visit KLS.

- Harold McGee | On Food and Cooking

According to renowned food scientist and writer Harold McGee, effective cookware has two main attributes:

  1. Even & Efficient Heating
  2. Chemically Inert & Durable

Here we will explore how and why multiclad stainless steel cookware is the best combination of those two attributes, as well as how to evaluate the quality of multiclad stainless steel cookware.

Even & Efficient Heating

Cookware is made out of two basic types of materials:

Insulators such as glass, ceramics, or earthenware conduct heat very inefficiently because of their molecular structure. They can be used effectively in ovens but not on the stovetop.

Conductors are metals such as copper, aluminum, or cast iron that conduct heat much more efficiently given the free flow of electrons in metals. However, not all conductors are equally efficient - heat flows significantly better in copper and aluminum than cast iron, carbon steel, or pure stainless steel.

Thermal Conductivity (Btu/hr.ft.degF):

 Copper Aluminum Cast Iron Carbon Steel 218 126 27.7 25.9

Let's compare evenness of heating in three different types of cookware:

1. Thick Pan, Low Conductivity: Cast Iron, Carbon Steel

Because of the relatively low conductivity of cast iron and carbon steel, heat travels slowly through these pans. Combined with their thickness, this creates hot spots on the cooking surface that are unlikely to even out because of the heat lost at the surface via radiation.

2. Thin Pan, High Conductivity: Aluminum, Thin Multiclad Stainless

Heat travels much more quickly through aluminum than cast iron or carbon steel. However, when a highly conductive metal is used in only a relatively thin layer, it can create hot spots, as well as other problems in cooking performance.

3. Thick Pan, High Conductivity: Quality Multiclad Stainless

When there is a thicker layer of aluminum to travel through, the heat in the pan has a better opportunity to distribute itself evenly. This creates a cooking surface with little to no heat differential.

Material Combinations

In order to solve the problem of conductivity and reactivity, many types of cookware combine materials, using a conductive core and a non-reactive surface. However, these combinations all suffer from drawbacks in durability.

  • Non-stick pans cover conductive materials with various non-porous coatings that don't directly react with foods. However, these coatings will degrade at high temperatures and are prone to scratching and chipping.
  • Enameled cast iron uses a thin layer of ceramic on the surface to prevent chemical interaction. The surface can, however, chip, scratch or crack, exposing the cast iron beneath and leaving an uneven cooking surface.
  • Anodized aluminum uses a chemical process to create a thick layer of non-reactive oxidized aluminum on its surface. However, your dishwasher and certain cleaning agents will stain and degrade this surface.

Clad Stainless Steel

Clad stainless is a cookware construction that solves these problems. By using an aluminum interior sandwiched between layers of stainless steel, you can combine the conductive properties of aluminum with the non-reactivity and durability of stainless steel.

Stainless steel is a uniquely well-designed material for the exterior of cookware. Its high chromium content naturally creates a thick oxide layer that prevents rusting and chemical interactions with food, while also providing an attractive shine. Stainless steel is also uniquely durable, offering a lifetime of cooking reliability.

Why Value Durability?

We believe that the lifespan of cookware should be measured in decades, not months or years. Cookware should consistently perform at the same level as the day you bought it, not force you to replace it once it corrodes, cracks, or scratches.

The company is the world’s best steel clad supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.

Cheap cookware becomes much more expensive when you have to replace it on a regular basis.

What is the purpose of the middle layer in a clad knife with 3 steels?

What is the purpose of the middle layer in a clad knife with 3 steels?

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Post by Robstreperous » Tue Feb 23, 2:49 pm

[On edit: Changed this post title after @Mauichef's explanation below corrected my misunderstanding of san mai.]

I was speaking with a friend about her favorite knife which happens to be a san mai construction and she asked me a question I'd never considered:

The purpose of the edge steel is obvious. You cut with it. The purpose of the cladding steel is equally obvious. It's the outer layer of the knife.

What is the purpose of the middle layer? I theorized it might act as some sort of binder or transitional layer to toughen the softer cladding steel but.. the truth is... I really have no idea.

So what's the answer here? Why add that middle layer?

Thanks.. Last edited by Robstreperous on Tue Feb 23, 3:35 pm, edited 1 time in total.

Re: What is the purpose of the middle layer in a san mai blade?

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Post by ronnie_suburban » Tue Feb 23, 2:52 pm

Isn't the middle layer the edge steel? I know so little. =R=
Half of cooking is thinking about cooking.

Re: What is the purpose of the middle layer in a san mai blade?

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Post by Robstreperous » Tue Feb 23, 2:56 pm

I think san mai loosely translates to 3 flat things. During forging cladding is laid on the bottom middle layer in the middle edge steel on the top. Then the knife is folded in on itself so the edge steel meets and the middle layer is sandwiched inbetween the edge steel and cladding.

Re: What is the purpose of the middle layer in a san mai blade?

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Post by mauichef » Tue Feb 23, 2:57 pm

I'm confused...what middle layer? The middle layer is the cutting steel.
San-mai means 3 layers or 3 parts.
The middle Hagane and the 2 outer, Jigane.
I must be missing something here

Re: What is the purpose of the middle layer in a san mai blade?

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Post by mauichef » Tue Feb 23, 3:00 pm

Robstreperous wrote: ↑Tue Feb 23, 2:56 pm I think san mai loosely translates to 3 flat things. During forging cladding is laid on the bottom middle layer in the middle edge steel on the top. Then the knife is folded in on itself so the edge steel meets and the middle layer is sandwiched inbetween the edge steel and cladding.

Thats not quite right.
San-mai are 3 pieces of steel. They are layered on top of each other and forge welded.
Soft, cutting , soft.
There is no folding over of any steel in the making of a billet of true san-mai.

Re: What is the purpose of the middle layer in a san mai blade?

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Post by Robstreperous » Tue Feb 23, 3:20 pm

mauichef wrote: ↑Tue Feb 23, 3:00 pm
Robstreperous wrote: ↑Tue Feb 23, 2:56 pm I think san mai loosely translates to 3 flat things. During forging cladding is laid on the bottom middle layer in the middle edge steel on the top. Then the knife is folded in on itself so the edge steel meets and the middle layer is sandwiched inbetween the edge steel and cladding.

Thats not quite right.
San-mai are 3 pieces of steel. They are layered on top of each other and forge welded.
Soft, cutting , soft.
There is no folding over of any steel in the making of a billet of true san-mai.

Thanks for straightening me out Ray. I guess I need to figure out how to reword the question then.

I've got a knife with an edge steel, a mid layer steel, and the outer cladding. What's the purpose of the middle steel?

Re: What is the purpose of the middle layer in a san mai blade?

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Post by enjay » Tue Feb 23, 3:26 pm

Edge steel : san mai :: hand : arm in a sleeve

Re: What is the purpose of the middle layer in a san mai blade?

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Post by Ozno_flash » Tue Feb 23, 3:32 pm

Rob -> Unless you pull a rabbit out of a hat with a pic of some knife out of left field, I don't think you are seeing what you think you are seeing. Most likely you are mistaking the bevel transition from the edge to the cladding as a extra layer of steel based on it looking different in some knives.

What you are looking at most likely is Mauichef's pic in the middle where a middle layer is surrounded by two layers. In some knives you can actually make out the different layers on the back of the spine if it doesn't wrap around.

Re: What is the purpose of the middle layer in a san mai blade?

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Post by Robstreperous » Tue Feb 23, 4:06 pm

Ozno_flash wrote: ↑Tue Feb 23, 3:32 pm Rob -> Unless you pull a rabbit out of a hat with a pic of some knife out of left field, I don't think you are seeing what you think you are seeing. Most likely you are mistaking the bevel transition from the edge to the cladding as a extra layer of steel based on it looking different in some knives.

What you are looking at most likely is Mauichef's pic in the middle where a middle layer is surrounded by two layers. In some knives you can actually make out the different layers on the back of the spine if it doesn't wrap around.
Could be.... Let me check with Tim Johnson. He did one for me a couple of years back using this stuff. I need to check my notes but I really thought it was 3 layers.

Re: What is the purpose of the middle layer in a clad knife with 3 steels?

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Post by Bensbites » Tue Feb 23, 4:26 pm

5 layers is gomia I think. The new trend I am seeing is copper. The two reasons, 1) it looks good to many, 2) using copper as a shim is different than forgewelding steel. Copper melts below temps where you forge.

The knife above could be carbon migration... that’s still three layers but the carbon can move between forging and heat treating.

Re: What is the purpose of the middle layer in a san mai blade?

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Post by mauichef » Tue Feb 23, 4:38 pm

Robstreperous wrote: ↑Tue Feb 23, 3:20 pm
mauichef wrote: ↑Tue Feb 23, 3:00 pm
Robstreperous wrote: ↑Tue Feb 23, 2:56 pm I think san mai loosely translates to 3 flat things. During forging cladding is laid on the bottom middle layer in the middle edge steel on the top. Then the knife is folded in on itself so the edge steel meets and the middle layer is sandwiched inbetween the edge steel and cladding.

Thats not quite right.
San-mai are 3 pieces of steel. They are layered on top of each other and forge welded.
Soft, cutting , soft.
There is no folding over of any steel in the making of a billet of true san-mai.
Thanks for straightening me out Ray. I guess I need to figure out how to reword the question then.

I've got a knife with an edge steel, a mid layer steel, and the outer cladding. What's the purpose of the middle steel?
I think you need to post a pic. You are describing a knife with 5 layers and I've never heard of that before. Outside of the kind of damascus steel that Ben was discussing. Like copper layers between the steels. But I believe that is a form of damascus not awase. In fact Tim is making me a knife out of that kind of billet right now.

San-mai is a form of cladding (awase) that has a soft steel, hard steel, soft steel layering. The soft steel is NOT folded over the spine in true san mai.
If you take a soft steel and draw it out then bend it into a taco shape the hard steel can be inserted and forge welded. But that is not san-mai. That is called Warikomi.



Also do note that nowadays very few smiths laminate the billets themselves.
They buy pre laminated sheets or billets, then either hammer them or cut them to shape. Therefore there will always be 3 layers showing at the spine.

I think you are seeing the junction between Hagane and Jigane and thinking there is a 3rd steel there.

UNLESS.....

You are seeing a knife made in the way of swords in which case they do use a 3rd metal between the soft and hard steels. (Kawagane)

But I dont think it's the case here.

Re: What is the purpose of the middle layer in a clad knife with 3 steels?

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Post by Robstreperous » Tue Feb 23, 4:41 pm

I tried to send Tim a txt but wouldn’t you know it my txts to non iMessage aren’t working. Tomorrow.

Re: What is the purpose of the middle layer in a clad knife with 3 steels?

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Post by mauichef » Tue Feb 23, 5:31 pm

Bensbites wrote: ↑Tue Feb 23, 4:26 pm 5 layers is gomia I think. The new trend I am seeing is copper. The two reasons, 1) it looks good to many, 2) using copper as a shim is different than forgewelding steel. Copper melts below temps where you forge.

The knife above could be carbon migration... that’s still three layers but the carbon can move between forging and heat treating.
I guess Gomai is 5 layers of 2 different steels. Check out the cool diagram I found. Learn something new every day here

Re: What is the purpose of the middle layer in a clad knife with 3 steels?

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Post by ChefKnivesToGo » Tue Feb 23, 5:59 pm

The idea behind san mai construction is a simple solution to a problem. How to make a hard edge knife? The more you harden the steel the more chance there is that the knife will warp. Once a mono steel knife warps it’s time consuming to fix. You have to start over or toss it or tinker with it by hammering it cold and it will resist straightening like a spring. By cladding the knife in soft iron or soft stainless you can heat treat the edge steel quite high and if it warps, you can take advantage of that soft cladding and easily straighten the knife. It also allows the maker to save some money (iron and soft stainless steel are cheap) and to add some design elements like Damascus or many types of Nashiji and hammering finishes. All of these are pretty easy when using softer cladding.

This is why mono steel Japanese knives are rarely over HRC 60. Some examples are Masamoto VG, Konosuke HD2, Misono, Kanehide etc.
Mark Richmond
Co-Owner Chefknivestogo
https://www.chefknivestogo.com/newarrivals.html

Re: What is the purpose of the middle layer in a san mai blade?

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Post by Jeff B » Tue Feb 23, 6:20 pm

If you are looking for more details, kindly visit cladded plate.

Robstreperous wrote: ↑Tue Feb 23, 4:06 pm Could be.... Let me check with Tim Johnson. He did one for me a couple of years back using this stuff. I need to check my notes but I really thought it was 3 layers.

The gray colors you are seeing toward the bottom of the cladding is carbon migration that happens during forging and heat treating. That is a san-mai knife or three layers. A carbon core with a layer of stainless steel on each side. If God wanted me to be a vegetarian he wouldn't have made animals taste so good.