Scrap blade steel

[Marulaghost]

Hi there new guy here though i've been lurking here for a while now.

My question pretty much involve the manufacturing process. I'm not sure if these would be considered company secrets but I'll ask anyway.

I understand that for the most part all the blanks for the blade would be cut out of large sheets. But I'm wondering what happens to the rest of the steel that won't become part of a knife. Would it be sent back to the original forgery or just tossed?

I'm also curious about what happens to scrap laminate sheets. Is there a way to separate the two steels or would they have to get blended if they were to be reforged?

Seeing as I'm on a roll here, my last inquiry would be about the shavings that come from grinding the blade blanks. Is it possible to gather that all up after the grinder is done?

I've been wondering about that ever since hearing that opinel keeps all their words shavings so they can light their furnace and keep warm in the winter

[zhyla]

I don’t know what Spyderco does but I imagine best case it goes in the recycle bin.

When I make a knife I usually keep any sizeable cutoffs. They are handy for making small tools like tiny chisels.

[Marulaghost]

I mean to me it would make perfect sense. Even scrap wood can be used for something even as simple as a door jam

I'm just wondering what spyderco would do with it considering their production volume. Would the remaining blade steel be enough for the original foundries to want back?

[FK]

Manufacturing plants will sell the steel scrap to dealers who specialize in that area. This includes sheets, tooling chips and grinding particles.
The steel will be loaded onto railroad cars along with automobile components, appliances and various steel scrap.
It ends up in "Mini Mills" that do not process iron ore and coke to make steel.
These steel Mini Mills are a significant part of the steel producing economy and contribute approx. 67% of USA steel production. The exact alloy content is adjusted at the electric arc furnace when the scrap is melted.

The traditional Integrated Steel mills making product from iron ore make up approx. 30% of steel production in the USA.

Some specialty steel producers also have Mini Mills to make stainless steels and high alloy steels.

Research Steel Mini Mills vs. Integrated Steel production for more details.

All of the knife manuf. worldwide use sheet steel for the blades,,,, forging is low volume and limited to mainly custom small production. The sheet steel can be hot rolled or cold rolled into coils. Some blades are punched out in a press and others are laser or water jet cut to shape.

Regards,
FK

[ferider]

Manufacturing plants will sell the steel scrap to dealers who specialize in that area. This includes sheets, tooling chips and grinding particles.
The steel will be loaded onto railroad cars along with automobile components, appliances and various steel scrap.
It ends up in "Mini Mills" that do not process iron ore and coke to make steel.
These steel Mini Mills are a significant part of the steel producing economy and contribute approx. 67% of USA steel production. The exact alloy content is adjusted at the electric arc furnace when the scrap is melted.

The traditional Integrated Steel mills making product from iron ore make up approx. 30% of steel production in the USA.

Some specialty steel producers also have Mini Mills to make stainless steels and high alloy steels.

Research Steel Mini Mills vs. Integrated Steel production for more details.

All of the knife manuf. worldwide use sheet steel for the blades,,,, forging is low volume and limited to mainly custom small production. The sheet steel can be hot rolled or cold rolled into coils. Some blades are punched out in a press and others are laser or water jet cut to shape.

Regards,
FK

Very interesting, FK. Is this true for powdered exotic steels as well ? I would imaging that "CPM scrap metal" could just be ground and reused to make new sheets ? Just wondering.

Roland.

[abbazaba]

I saw these for sale in a store once, almost bought a sheet

[The Meat man]

I saw these for sale in a store once, almost bought a sheet

Interesting! Do you know what steel?

[zhyla]

Manufacturing plants will sell the steel scrap to dealers who specialize in that area.

That makes sense for mainstream manufacturing steels, but do they do this for cutlery/tool steels too? Or do they not care about the composition much?

[abbazaba]

I saw these for sale in a store once, almost bought a sheet

Interesting! Do you know what steel?

German 4116 supposedly.

[kodai78]

How expensive was it? Asking for a friend.

[abbazaba]

I honestly don't remember, but I think it was around $100.

[FK]

Theoretically if you are 100% certain of the exact original manuf and grade of steel, the scrap sheet can be reused in the furnace with new steel. The problem is what if somehow one sheet of different grade is mixed in,,, it destroys the composition of the entire new melt. It would be too expensive to do a metallurgy lab test on every sheet of scrap, then inventory each piece and secure it until it is returned to the steel mill.

More efficient to make a new melt (furnace heat) with known alloys. Many of our CPM steels have fractions of a percent for quality control. Scrap is a gamble and not worth it to the steel producer.

One of our customers is a specialty stainless steel producer,,,, their Mini Mill makes alloys for kitchenware, pots, pans and various products for the food industry,,, not terribly concerned about exact percentages of alloys.

To compete with imported steel from Asia and Europe, we must keep the costs low and automate as much as possible.
I visited a large Mini Mill several years ago where their electric furnace holds 50 tons of steel,,, a very large magnet picks up 20 tons of scrap at a time and drops it into the vessel, close the top and heat to liquid. A operator in silver heat resistant suit approaches the furnace with a long rod,, takes a small sample and goes to the metallurgy lab. They quickly get analysis and add any additional alloys as needed. The steel is immediately poured into a continuous hot cast plate and run through a 6 stand rolling mill. Note that 30 years ago this plant would employ 500-700 people,,, today about 50 staff, including admin, run the entire operation.

Our knife steels are made on a much smaller scale, I have visited Carpenter in PA, Crucible and several others with specialty steels. Sandvik visited with their chief metallurgist, he laughed and told me his guys are always experimenting with new CPM processes to make alloys,,, most end up in custom knife blades for the lab techs.
Hitachi owns a percentage of our Tokyo operations and when they visit the USA we have interesting discussions on steel alloys.

One of the large machine shops I deal with is in Ohio,,,, the President told me he can order steel made in Russia or South America delivered to his plant at a price lower than the USA mills actual cost of production (no profit included). His head of purchasing tried one order,,,, the quality was so poor, the product had to be scrapped and remade,,, lost money on that test run.

FK

[ferider]

Thanks !

[The Mastiff]

Interesting stuff FK. When I have bought steel it came with a composition sheet listing the exact composition of the steel. Tool steels and others have a set composition so all A2 or D2 steels should have comps that are pretty close to other AISI / SAE or JIS steels of the same grade. If you look at the comp sheets that come with the steels you can see the effect recycling has. Tiny amounts of things not listed in the specs will show up that got there because recycling steel with shredded steel in a pile lifted up will have things like copper,aluminum, selenium, lead and dirt, rocks and plastic and whatever else was in that pile of scrap steel that got into the melt. Yet it is still A2 or D2 or whatever and has the right amounts of chrome, moly, etc. I have seen people on forums who saw the posted comp deny it was A2/D2/whatever because of the additional stuff. You can get more pure/cleaner steels from processes like vacuum remelting but they do cost more. Powder processing steels are generally going to be cleaner too for obvious reasons.

joe

[FK]

We call the paperwork with steel shipments "mill specs" they are trusted if from reputible distributors. Some imported steels are not very accurate. The mills produce large amounts of steel, it is shipped to distributors who cut it into smaller pieces for end use machine shops.

At the temps the electric arc furnaces operate,, most of the impurites will escape as gasses.

FK

[Marulaghost]

I honestly didn't think I'd get such awesome responses. This is fantastic! You guys rock

[The Deacon]

Won this in a Spyderco contest a few years back...

[The Meat man]

Won this in a Spyderco contest a few years back...

Really?!

What steel is that?

[The Deacon]

Really?!

What steel is that?

Pretty sure it's S30V.

[Dutchman]

Won this in a Spyderco contest a few years back...

Really?!

What steel is that?

My guess would be that is before heat treat.