Heat Treating - Can someone help me understand what Murray Carter is doing?

kuraki said:
Hitachi's resistance to selling outside their domestic users doesn't surprise me at all. Dealing with Fanuc, Okuma, Toyoda (yes with a "D"), over the years, I groan whenever any issue requires getting bumped from the domestic (US) office to the Japan offices. Even though they sell us their machines/technology with willing eagerness, I can't help but feel they resent having to do it.

You can also see the stubborn resistance to change. Fanuc makes extremely stable, dependable machine controls. I haven't bought a machine since 2012 but even then, they still resisted installing a USB port on one, and to my knowledge still do not offer it as standard, only a purchasable option. This is quite ridiculous, even on a networked machine, having a USB port either as a backup NC program delivery system, or for creating program changes from a laptop at the machine, is incredibly useful and such low cost as to make it mind boggling that in 2016, it's not standard, but RS232 still is. Even on Windows based controls.

Our brand new Okuma MCR double column mill burned up the right angle head bearings after only weeks of use because of a failure to check whether the oil mister that lubricated it was actually delivering oil or not. Okuma would not let Okuma USA repair it. It had to be sent to Japan and took months to be fixed. We're talking about replacing spindle bearings, some helical bevel gears, adjusting for backlash and run out. Something done all over the place on a daily basis. And given the relative rarity of that device there wasn't one on the shelf anywhere.

Things like that I can intellectually grasp a cultural difference, but still cannot wrap my head around it and understand.
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Even worse with mazak. But man can that machine perform! :-)


Sent from my iPhone using Tapatalk
 
I have good experiences with Mazak. Unfortunately at my company before my time the guys were soured on them from experience with an old used machine. And we pick machine purchases by committee. I almost had them convinced we should buy an Integrex at one point, but they decided to go with a DMG, which everyone regrets.
 
He buys it from Dictum in Germany, where mot of us who use a good bit buy from. With the dollar strong right now, it is pretty darn cheap. Some types are available in 1 meter length, which is really nice.
The other supplier is Workshop Heaven in the UK.
 
lazlo said:
Funny - Din 1.2519 is AISI O7 is Hitachi Super Blue. It's a tool steel made for planer blades and paper cutting shears.

http://sij.metalravne.com/steelselector/steels/OW3.html
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Yeah, they're pretty close, but not identical. Hitachi blue has less chromium (.2–.5%) and is shallower hardening, as far as I understand it. 1.2519 is also one of Roman Landes' favorite steels for thin edges, which should count for something in favor of Hitachi blue as well.
 
Tenebr0s said:
Yeah, they're pretty close, but not identical. Hitachi blue has less chromium (.2–.5%) and is shallower hardening, as far as I understand it.
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Varies from vendor to vendor. The AISI O7 spec specifies 1.1 - 1.3% carbon, .35 - .85 chromium, 1 - 2% tungsten (for red hardness). Super Blue is 1.3% carbon, .5% chromium, 2% tungsten.
The Germans have a family of DIN designations to micromanage the chromium, tungsten: I.2414 1.2419. 1.2442. l.2516, 1.2519. The important thing is that these are all dirt common tool steels used in industry for 70 years.

 
Totally agree. Nothing magical about the steel.

The hype for Hitachi blue is silly (O7 and 1.2519 are very similar and common); but that doesn't mean it's not first-rate for thin edges.
 
Tenebr0s said:
The hype for Hitachi blue is silly (O7 and 1.2519 are very similar and common); but that doesn't mean it's not first-rate for thin edges.
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Oh yeah, those alloys are design for thin, keen edges at very high hardness, with low impact strength. Tailor made for a chef knife.
 
I use 1.2519 as well and i agree with Tenebros.
As many high strenght steels, they are in the area where they can be subjected to misunderstanding, hypes and undeserved bad reputations.
They will easily get hard, but to say they are easy to HT is BS.

Not many industrial raw materials/ intermediate products are being sold to the private citzen in small amounts... IMHO the fear of getting bad reputation from the unexperienced smiths it is not even considered, the management of small orders and related cost is.
 
Trust me, it is not just the small orders that is the problem. Many folks, including suppliers, have tried to make orders in the tons and have been told no.
 
stezann said:
I use 1.2519 as well and i agree with Tenebros.
As many high strenght steels, they are in the area where they can be subjected to misunderstanding, hypes and undeserved bad reputations.
They will easily get hard, but to say they are easy to HT is BS.

Not many industrial raw materials/ intermediate products are being sold to the private citzen in small amounts... IMHO the fear of getting bad reputation from the unexperienced smiths it is not even considered, the management of small orders and related cost is.
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What makes these steels so hard to heat treat?

Hoss
 
they are hypereutectoids, and alloyed with W, in the case of 1.2519(Blue); the fact itself you find them chippy when heat treated "by eye in a forge" should be explanatory enough.
But even the White, hypereutectoid steel, simple in that it has pretty much just iron and carbon it's difficult to HT BECAUSE it has nothing else to help with slowing grain growt, avoiding precipitation of cementite at the grain boundaries and with dept of hardenability....a chippy steel for the backyard HT'er it's round the corner very easily.
On the other hand if what they say it's correct one could count on steady makeup numbers due to the purity granted by the Hitachi production processes, and this would provide repeatable performances once the variables of HT had been addressed, and claimed vibrant hamons, i don't know.
I understand there are a lot of alternatives in the same game field to choose from, and one should choose its favorite steel among the ones at hands. And i am the first getting suspicious when i hear of a steel surrounded by hype claims, being suitable only for a few genious smiths, but i wouldn't easily disregard steels i might not really know much about.

I don't want this to be a flame war, i'd been saying the same to a Japanese smith complaining 52100 as chippy and easy to heat treat in the same time :)
 
I think hard to heat treat means you need reasonable temp control, and the right quench medium, plus the ability to test the results to hone in your equipment. Basically, $2000-$2500 in equipment to get it right and repeatable. Once dialed no steel that we use is particularly difficult to heat treat with the right equipment.
 
All of the knives I tested and owned were made by Japanese or Japanese trained smiths.

These steels are designed to respond quickly to thermal cycling. They are made to move from forging to normalizing to annealing to quenching to tempering quickly. Murray Carter has a vidio that shows him making a knife in less than 30 minutes. He forge welds the core, forges out the blade, normalizes, anneals, hardens, tempers, grinds the blade and mounts a pre made handle in less than 30 minutes.

I lived in Japan for two years. I visited every kitchen knife maker, sword maker and custom knife maker I could find. I watched them make knives and not one of them had a complicated heat treatment. I believe that all steels require practice to heat treat properly. That does not make them difficult to heat treat.

Hoss
 
Lazlo, the bad news is that 1.2442/115W8 is no longer dirt common as its big users switched to HSS at the behest of the bean counters. I jokingly call that stuff Blue #1.5 because it has carbon content like #2 and tungsten content more like #1. . The only known knife maker source for that stuff of late has been from a special smelt that Achim Wirtz did at Lohmann. The others that you listed are still available. As best as I can tell, that is because they are still used heavily by the timber industry whereas 1.2442 was primarily used by the metals industry. I was told by Herr Wirtz that you could take that stuff up to 64 for kitchen knives, but for "hard use' blades, you should higher than 62. It is pretty darn tough that that hardness.
lazlo said:
Varies from vendor to vendor. The AISI O7 spec specifies 1.1 - 1.3% carbon, .35 - .85 chromium, 1 - 2% tungsten (for red hardness). Super Blue is 1.3% carbon, .5% chromium, 2% tungsten.
The Germans have a family of DIN designations to micromanage the chromium, tungsten: I.2414 1.2419. 1.2442. l.2516, 1.2519. The important thing is that these are all dirt common tool steels used in industry for 70 years.

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DevinT said:
All of the knives I tested and owned were made by Japanese or Japanese trained smiths.

These steels are designed to respond quickly to thermal cycling. They are made to move from forging to normalizing to annealing to quenching to tempering quickly. Murray Carter has a vidio that shows him making a knife in less than 30 minutes. He forge welds the core, forges out the blade, normalizes, anneals, hardens, tempers, grinds the blade and mounts a pre made handle in less than 30 minutes.

I lived in Japan for two years. I visited every kitchen knife maker, sword maker and custom knife maker I could find. I watched them make knives and not one of them had a complicated heat treatment. I believe that all steels require practice to heat treat properly. That does not make them difficult to heat treat.

Hoss
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this thread has certainly lost it's focus from the OP :-)
but anyway, I visited Murray in Dec last year for 5 days, since then in the last 11 months I've only worked with Hitachi laminated steels.
I don't have alot of experience but I would agree with Devin here, if I can do the HT, it's easy to HT :-)

My opinion is that it is in fact surprisingly easy and relatively fast.
As I mentioned earlier, one of the main reasons I like using this steel.

I remember in the class with Murray saying - "that's it?" meaning I was surprised at the simple procedure.

Following the proper steps I get 63-64 RC everytime.

regards
 
While I agree that once dialed in, any heat treat becomes repeatable or "easy", the problem is the variable of judging heat by eye. IIRC this was put to the test some years ago with well known smiths, who ended up being 100's of degrees off the mark. Also the fact that you can have a crappy knife read at 63HRC. That number doesn't tell you the whole story of the internal structure.
 
Not to start a flame war on heat treat methods, but Jim said it earlier. Traditional smiths make good knives in spite of their methods, not because of them. Traditional smiths are selling an image, a mystique. I have no problem with that. If people want to buy that mystique, they are free to do so. Most of my customers have simply said the upcharge for hitachi steels was not worth it compared to 52100 or W2. I've done a few hitachi blue #2 knives, but it wasn't the mystique that sold them, it was the tungsten and alloy banding in my stock.

Murray Carter has branded himself well, and he is a well known, successful knife maker, but one only has to look at his heat treat failure in FIF to see that a modern setup would have easily solved his problem.

The debate re:easy/hard is semantics. To get repeatable consistent results with hypereuctoid steels, you need strict temp control. My experience says +/-10f is the range that starts showing decreases in performance and inconsistencies in the steel structure. I don't care who you are, no human eye can recognize +/-10f in the 1400-1500f range.
 
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