Nagato/Mutsu armor

[wdolson]

ORIGINAL: wdolson
A few months ago somebody posted an article on some Yamato class armor the US tested after the war. It was made for one of Yamato's sisters and discarded. It may have been the Shinano.

ORIGINAL: Symon
Some data would be nice, my friend. "Some guy posted it" doesn't quite cut it.

I figured that my posting that would stir someone's memory. The person who posted the article in the first place may be reading this thread. I did say I couldn't find it.

I recall the article said that the USN found the thick armor to be very fragile and easy to penetrate.

Once again, some data would be nice. The statement is, of itself, a metallurgical non-sequitor. Fragility is a function of 'inclusions'. If one can make decent medium plate, one can make decent thick plate, so long as one has the requisite thickness on one's rolling mill. Face hardening is another issue, but it has nothing to do with the quality of the base-plate.

Hopefully somebody will remember the article and post the link.

They also tested some Japanese cruiser armor and it proved to be some of the best armor tested, exceeding British, German, and US armor of the same thickness.

That is rank, utter, nonsense. Sorry, Bill.

How the armor is made is another factor in its effectiveness. Japanese industry could produce very good armor of medium thickness, but when they went to thicker armor, they couldn't control the crystal size in the metal which made the resulting armor brittle.

Another metallurgical non-sequitor. I have a friend that can make a 6" boule of perfect crucible steel, in his backyard in 16 hours. There is no secret to steel. Face hardening is a bitch, but that has nothing to do with what's underneath.

The grand total of my formal metallurgy training was a few days in a strength of materials class over 20 years ago. I probably misremembered something from the article. I do recall the article said the steel was brittle due to a manufacturing defect.

I believe I read elsewhere the Germans were particularly good at making thick armor. It was another contributing factor to the ability of the Bismarck to take punishment.

Everybody who thinks on these things knows exactly what the parameters of Krupps finest were. Notwithstanding the "everything German is perfect" little kiddles, Krupp armor was pretty much average, and had nothing special to recommend it.

Have a doc with hundreds of contemporary primary sources to support this.

I recall the article making a comparison to German armor plate, but again I could be wrong. Ship armor is far from my area of expertise.

Bill

[Big B]

Gentlemen, the world's published leading expert on guns and armor plate for naval weapons and ships of the 2nd World War (whose work is readily accessible) is Nathan Okun.

His work speaks for itself....

ORIGINAL: wdolson

ORIGINAL: wdolson
A few months ago somebody posted an article on some Yamato class armor the US tested after the war. It was made for one of Yamato's sisters and discarded. It may have been the Shinano.

ORIGINAL: Symon
Some data would be nice, my friend. "Some guy posted it" doesn't quite cut it.

I figured that my posting that would stir someone's memory. The person who posted the article in the first place may be reading this thread. I did say I couldn't find it.

I recall the article said that the USN found the thick armor to be very fragile and easy to penetrate.

Once again, some data would be nice. The statement is, of itself, a metallurgical non-sequitor. Fragility is a function of 'inclusions'. If one can make decent medium plate, one can make decent thick plate, so long as one has the requisite thickness on one's rolling mill. Face hardening is another issue, but it has nothing to do with the quality of the base-plate.

Hopefully somebody will remember the article and post the link.

They also tested some Japanese cruiser armor and it proved to be some of the best armor tested, exceeding British, German, and US armor of the same thickness.

That is rank, utter, nonsense. Sorry, Bill.

How the armor is made is another factor in its effectiveness. Japanese industry could produce very good armor of medium thickness, but when they went to thicker armor, they couldn't control the crystal size in the metal which made the resulting armor brittle.

Another metallurgical non-sequitor. I have a friend that can make a 6" boule of perfect crucible steel, in his backyard in 16 hours. There is no secret to steel. Face hardening is a bitch, but that has nothing to do with what's underneath.

The grand total of my formal metallurgy training was a few days in a strength of materials class over 20 years ago. I probably misremembered something from the article. I do recall the article said the steel was brittle due to a manufacturing defect.

I believe I read elsewhere the Germans were particularly good at making thick armor. It was another contributing factor to the ability of the Bismarck to take punishment.

Everybody who thinks on these things knows exactly what the parameters of Krupps finest were. Notwithstanding the "everything German is perfect" little kiddles, Krupp armor was pretty much average, and had nothing special to recommend it.

Have a doc with hundreds of contemporary primary sources to support this.

I recall the article making a comparison to German armor plate, but again I could be wrong. Ship armor is far from my area of expertise.

Bill

[Alfred]

ORIGINAL: Symon

ORIGINAL: wdolson
A few months ago somebody posted an article on some Yamato class armor the US tested after the war. It was made for one of Yamato's sisters and discarded. It may have been the Shinano.

Some data would be nice, my friend. "Some guy posted it" doesn't quite cut it.

I recall the article said that the USN found the thick armor to be very fragile and easy to penetrate.

Once again, some data would be nice. The statement is, of itself, a metallurgical non-sequitor. Fragility is a function of 'inclusions'. If one can make decent medium plate, one can make decent thick plate, so long as one has the requisite thickness on one's rolling mill. Face hardening is another issue, but it has nothing to do with the quality of the base-plate.

They also tested some Japanese cruiser armor and it proved to be some of the best armor tested, exceeding British, German, and US armor of the same thickness.

That is rank, utter, nonsense. Sorry, Bill.

How the armor is made is another factor in its effectiveness. Japanese industry could produce very good armor of medium thickness, but when they went to thicker armor, they couldn't control the crystal size in the metal which made the resulting armor brittle.

Another metallurgical non-sequitor. I have a friend that can make a 6" boule of perfect crucible steel, in his backyard in 16 hours. There is no secret to steel. Face hardening is a bitch, but that has nothing to do with what's underneath.

I believe I read elsewhere the Germans were particularly good at making thick armor. It was another contributing factor to the ability of the Bismarck to take punishment.

Everybody who thinks on these things knows exactly what the parameters of Krupps finest were. Notwithstanding the "everything German is perfect" little kiddles, Krupp armor was pretty much average, and had nothing special to recommend it.

Have a doc with hundreds of contemporary primary sources to support this.

[/quote]

wdolson and Symon,

I think this is the thread wdolson referred to:

tm.asp?m=3527060&mpage=2&key=yamato

Post #37 from Disco Duck has the hyperlinks which I think have been alluded to.

Alfred

[wdolson]

The pictures look familiar, but I don't recall the article being on navweaps.com. The date of that post is about right. I recall it was in the last six months.

My memory for the details of this must be faulty.

Bill

[geofflambert]

ORIGINAL: Symon


Another metallurgical non-sequitor. I have a friend that can make a 6" boule of perfect crucible steel, in his backyard in 16 hours. There is no secret to steel. Face hardening is a bitch, but that has nothing to do with what's underneath.

I believe I read elsewhere the Germans were particularly good at making thick armor. It was another contributing factor to the ability of the Bismarck to take punishment.

Everybody who thinks on these things knows exactly what the parameters of Krupps finest were. Notwithstanding the "everything German is perfect" little kiddles, Krupp armor was pretty much average, and had nothing special to recommend it.

Have a doc with hundreds of contemporary primary sources to support this.

[/quote]

I use that "I have a friend" trick all the time, good work. Bet he couldn't make Damask steel.

OT a bit. I bought some Chinese manufactured sewing needles and every time I threaded the needle and tried to sew (this is extraordinarily difficult for gorns, with our claws) the eye would break. Every single flipping time. I got some Czech manufactured ones and they were excellent. I think generally Czech steel metallurgy is second to none, these days, and the US isn't even 3rd. Also from my experience in mechanical engineering, Italian metallurgy in brasses and bronze is the best there is. Remember when (some of you) were young and "Made in Hong Kong" and "Made in Japan" told you the stuff was crap? Then later, especially in regard to Japan, that became a symbol of quality. The Chinese know how to produce quality things in many categories, but they often choose not to when there's a US buck to be made.

[geofflambert]

Oh, and JWE, you need to stop drawing the moderator into arguments, that's a conflict of disinterest. (That's a joke Bill)

[String]

ORIGINAL: Symon

ORIGINAL: wdolson
A few months ago somebody posted an article on some Yamato class armor the US tested after the war. It was made for one of Yamato's sisters and discarded. It may have been the Shinano.

Some data would be nice, my friend. "Some guy posted it" doesn't quite cut it.

I recall the article said that the USN found the thick armor to be very fragile and easy to penetrate.

Once again, some data would be nice. The statement is, of itself, a metallurgical non-sequitor. Fragility is a function of 'inclusions'. If one can make decent medium plate, one can make decent thick plate, so long as one has the requisite thickness on one's rolling mill. Face hardening is another issue, but it has nothing to do with the quality of the base-plate.

They also tested some Japanese cruiser armor and it proved to be some of the best armor tested, exceeding British, German, and US armor of the same thickness.

That is rank, utter, nonsense. Sorry, Bill.

How the armor is made is another factor in its effectiveness. Japanese industry could produce very good armor of medium thickness, but when they went to thicker armor, they couldn't control the crystal size in the metal which made the resulting armor brittle.

Another metallurgical non-sequitor. I have a friend that can make a 6" boule of perfect crucible steel, in his backyard in 16 hours. There is no secret to steel. Face hardening is a bitch, but that has nothing to do with what's underneath.

I believe I read elsewhere the Germans were particularly good at making thick armor. It was another contributing factor to the ability of the Bismarck to take punishment.

Everybody who thinks on these things knows exactly what the parameters of Krupps finest were. Notwithstanding the "everything German is perfect" little kiddles, Krupp armor was pretty much average, and had nothing special to recommend it.

Have a doc with hundreds of contemporary primary sources to support this.

[/quote]

I suspect the article being referred to is this one : http://www.combinedfleet.com/metalprp2002.htm
by Nathan Okun. Search the article for "JAPANESE VICKERS HARDENED NON-CEMENTED FACE-HARDENED ARMOR (VH)" to find the passage detailing the high quality armor plate and which also sheds some light on the penetrated armor plate currently on display in the US.

An experimental 7.21" (18.15cm) VH plate (#3133 at NPG, Dahlgren) seems to have been made from a German KC n/A (see above) specification added to an otherwise standard VH plate. It had a 535 Brinell maximum face hardness 3% into the plate, which is harder than all heavy VH production plate, though only by a small amount, with the hard point the closest to the face surface (about the same distance from the face surface (0.22" (0.55cm)) as with most cemented non-German KC-type plates), and a back hardness of 210-215 Brinell, which is slightly higher than production VH, but still well below average foreign World War II-era KC-type plates. The steel used was identical to the production VH plates that had been tested previously (rather dirty steel again of circa-1910 quality) and the hardness curve showed a typical VH-style pattern for the high-hardness portion. However, the major difference between this plate and all other VH plates was that the transition layer was much wider, extending to 43% into the plate (57% unhardened back), almost identical to German KC n/A, though with a higher average hardness than KC n/A in the decrementally hardened region. Since Germany and Japan were allies during World War II, it is not surprising that the Japanese may have obtained such information on German Krupp armor and made test plates to compare it with their own armor. The U.S. test personnel at the U.S. N.P.G. did not expect it to be much different from the production VH plates, especially due to its relatively poor steel quality. However, this plate was found to be the best face-hardened plate of its thickness ever tested at the U.S. N.P.G.! (The next best plate of similar thickness was also an experimental non-cemented face-hardened plate of 7.6" (19.3cm) thickness made by Carnegie-Illinois Steel Corporation during World War II, which was only slightly inferior to this VH plate.) It required the late-World War II, improved, super-hard-capped (650-680 Brinell all the way through) U.S. 8" (20.3cm) Mark 21 Mod 5 AP projectiles to completely penetrate this plate in "effective" condition at 30o obliquity (the standard U.S. armor test in World War II)--the older Mod 3 projectiles, similar but with a maximum cap hardness of 555-580 Brinell, were torn up badly even when they completely penetrated (a rare feat against these U.S. projectiles!) and needed a much higher striking velocity to do so. Against the Mod 5 projectile, my calculations indicate that this plate was 1% better on an equivalent thickness basis than an average KC n/A plate (probably because the VH plate does not lose any resistance due to the existance of the thin, but very brittle, cemented layer used in KC n/A armor), meaning that it would take an average 7.28" KC n/A plate to replace this 7.21" VH plate--a pretty big improvement from regular VH armor in a single step! The U.S. test personnel were at a loss to explain this, but to me it seems that the Japanese personnel used the face tempering process of KC n/A, possibly with some of their own expertise added, in addition to just increasing the chill thickness. Japanese metallurgists (and most other technical personnel) obviously were (and are still) just as good as anybody else when allowed to set their own standards of excellence, as the post-World War II world has discovered big-time!

and

NOTE: The 26" (66cm) VH turret face plates on the YAMATO Class were inclined back 45o and were the only plates that could not be completely penetrated by any gun ever put on a warship--these plates could be holed at point blank range by a newly-lined World War II U.S. Navy 16"/50 gun with late-World War II hard-capped AP projectiles, but even these projectiles would always ricochet; the YAMATO's own 18.1" (46cm) hard-capped AP projectiles, which were designed to an only slightly-improved British circa-1921 armor penetration specification, could not even make a hole in these plates at any range, though the impacts might crack them!

[Dili]

http://www.navweaps.com/index_nathan/me ... pt2009.htm

An article where there is a round up of armor types and its qualities.

[String]

ORIGINAL: Dili

http://www.navweaps.com/index_nathan/me ... pt2009.htm

An article where there is a round up of armor types and its qualities.

It's the same article, just on a different website

[offenseman]

Is it very hard to penetrate the actual facts of this subject.

+1 on the Czech steel too BTW. Some of the best steel and artisan metal workers are in Czech Republic.

[pontiouspilot]

wplson's thread mentioned above re Yamato armour is under War Room Jan 21'14, derhexer's thread (can you tell I'm too incompetant to paste it over here). In that thread there is under someone's response the test item on actual armour.

[Symon]

ORIGINAL: geofflambert
I use that "I have a friend" trick all the time, good work. Bet he couldn't make Damask steel.

You would lose. I met him when the Yacht Club wanted a replica cannon for a sunset gun. He cast a perfect replica of an English brass 1726 4 pdr; carriage and everything. His shop makes almost all the replica weapons for Hollywierd. That's his income, but his interest is the history of metalurgy. He's been on CBS and had several 'specials' on PBS.

A very interesting man, that understands more about metallurgy than you will ever know. He is the only person in the world, since the 10th century, to make an "Ulfbert". He made three. The first is at Upsalla, the second is in the Smithsonian.

You have a wonderful day now, heah!

[geofflambert]

Had to look that up. These must be total crap.

http://www.darkknightarmoury.com/p-9505 ... sword.aspx

[witpqs]

ORIGINAL: geofflambert

Had to look that up. These must be total crap.

http://www.darkknightarmoury.com/p-9505 ... sword.aspx

You can find lots of swords for sale at that price and they must be the equivalent of $5 knives. One that gets housed at the Smithsonian... different story!

[msieving1]

ORIGINAL: witpqs

ORIGINAL: geofflambert

Had to look that up. These must be total crap.

http://www.darkknightarmoury.com/p-9505 ... sword.aspx

You can find lots of swords for sale at that price and they must be the equivalent of $5 knives. One that gets housed at the Smithsonian... different story!

Those particular swords are made by Windlass Steel Crafts, an Indian manufacturer of edged weapons. They're mass-produced, but are of reasonably good quality. People do use Windlass products for medieval style martial arts, and Windlass makes ceremonial swords for the military of several countries, including the US and UK. To be slightly on-topic, Windlass started during World War II making kukris for the British Army.

[witpqs]

ORIGINAL: msieving1

ORIGINAL: witpqs

ORIGINAL: geofflambert

Had to look that up. These must be total crap.

http://www.darkknightarmoury.com/p-9505 ... sword.aspx

You can find lots of swords for sale at that price and they must be the equivalent of $5 knives. One that gets housed at the Smithsonian... different story!

Those particular swords are made by Windlass Steel Crafts, an Indian manufacturer of edged weapons. They're mass-produced, but are of reasonably good quality. People do use Windlass products for medieval style martial arts, and Windlass makes ceremonial swords for the military of several countries, including the US and UK. To be slightly on-topic, Windlass started during World War II making kukris for the British Army.

Good to know. Thanks!

[Symon]

ORIGINAL: msieving1
Those particular swords are made by Windlass Steel Crafts, an Indian manufacturer of edged weapons. They're mass-produced, but are of reasonably good quality. People do use Windlass products for medieval style martial arts, and Windlass makes ceremonial swords for the military of several countries, including the US and UK. To be slightly on-topic, Windlass started during World War II making kukris for the British Army.

Yep. Lots of fakes out there, just like in the 10th century.

If you want the real deal, you should talk to John Clements or Fredrik Ljungqvist. John is the man who reproduced the crucible steel boule in his back yard and went on to make the first real ulfberht blade since the 10th century. Because he is a normal person, who actually does things that don’t turn out like ‘received wisdom’ says they should, he is cordially hated by much of the “sword and sorcery” community.

John’s a nice guy. Kinda short, nice bushy beard, likes scotch, really loves his work, knows more about metal than I ever will. Cast and turned a cannon for my Yacht Club and helped me understand a bit more about why some guns are just that much better than others (talking SA arty here).

It is his blade in the Smithsonian. Not some poor carbon copy (pun intended).

Ciao. John

[jwilkerson]

BTW, the armor rating for Mutsu/Nagato came from several sources but a new (at the time) Polish source was high on the list. As I unpack (just moved) I'll run across it and at least post the name/author. The Polish source named Japanese sources, as well as others, in its source list.

When Breyer first came out, in the 70s ... it was a "hot" item ... but it is probably a bit dated these days. I have a well worn copy.

[Dili]

There is a discussion here: http://warships1discussionboards.yuku.c ... s-on-armor


Pdf from one of particpants: http://www.navweaps.com/index_lundgren/ ... ndgren.htm

[Fallschirmjager]

What has not been mentioned is that 33mm of in game armor does not make a hell of a lot of difference.
You have to look at what the Mutsu/Nagato is being hit by in game. 33mm is not going to make a difference whether or not a 1000 lb GP bomb from a US divebomber penetrates the deck. It is not going to make a difference in any shell 12" or larger according to the editor ratings.
The only question is can the deck armor stop a 8" shell with that extra 33mm of armor and looking at the editor and my very rudimentary understanding of the armor penetration code, the answer is no. A 8" shell even at a very short range will still not penetrate even if the deck armor is the wrong thickness in game.

I am all for in game accuracy. But I don't think 33mm of deck armor has won or lost a game yet nor do I even think it has made the difference between one of those ships being sunk despite the tens of thousands of games played to this point.