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Stephan Hall




Location: Germany
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PostPosted: Thu 31 Jan, 2008 5:22 am    Post subject: Case hardened Armor         Reply with quote

Bestarmor.com offers to case harden their cold rolled armor they claim that the steels properties can be improved to almost spring steel quality .
Has anyone tested or owns such armor.
does anyone else sells case hardened armor.
Is the armour fully hardened or surface hardened.
it would be worth a testing i think.
a cold rolled steel breast and backplate costs about 1000 euro
casehardened 230 euro more
spring steel 1.0mm 1500euro
1.5mm 1700euro

so who knows something??????????
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Jean Thibodeau




Location: Montreal,Quebec,Canada
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PostPosted: Thu 31 Jan, 2008 5:41 am    Post subject:         Reply with quote

Well, case hardened by definition is greater surface hardness on a softer core: The core could also be hardened but not as much as the surface.

The idea being that maximum hardness on the surface means that weapons would have more difficulty bitting into the steel and the softer core would prevent the armour from being brittle.

The specifics of this makers armour I have no personal experience with them ? Could be very legit or marketing hype like " battle ready ".
( Assuming that this maker has a good reputation for honnesty and quality then it may well be worth the price )

No doubt that in principle armour was sometimes case hardened historically but like anything it can be well done or badly done.

You can easily give up your freedom. You have to fight hard to get it back!
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Allan Senefelder
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Location: Upstate NY
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PostPosted: Thu 31 Jan, 2008 7:27 am    Post subject:         Reply with quote

What I imagine is being done is this. There is a case hardeing paste that is applied to a surface, that surface is then heated to red and allowed to cool and the paste w/ heat case hardens the steel surface. It been around for a while, back prior to a during WWII a number of countries including the US used this stuff on helmets, it allowed the use of lower grade steel ( thus allowing the better grade steels to be used for other purposes like gun and artillery barrels) for helmets. Farmers used it to treat the edges of agricultural equipment after repairing pieces broken out of an edge or after grindign a new edge, alot of DPW's did the same thing with thier snow plow blades. McMaster-Carr used to carry the stuff I don't know if they still do or how common its found these days.
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James Arlen Gillaspie
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Location: upstate NY
Joined: 10 Nov 2005

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PostPosted: Thu 31 Jan, 2008 8:47 am    Post subject:         Reply with quote

My very first attempts at heat-treating armour began with casehardening. A big concern was holding the pieces at proper temperature to achieve good penetration of the carbon (the hotter, the better, up to a certain limit) and the inevitable side - effect... warping. Quenching makes it worse. Spring steel isn't (well, certainly shouldn't) be held at such high temperatures before quenching, so it warps less. In my experience, case hardening can indeed significantly improve the characteristics of thicker items such as helms and breastplates, but can make thinner items a bit brittle. It does make it a lot harder to scratch the surfaces.
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Stephan Hall




Location: Germany
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PostPosted: Thu 31 Jan, 2008 11:58 am    Post subject:         Reply with quote

ok case hardening means to harden the surface of a steel wich has not enough carbon to be hardened this can be achieved by adding carbon (carburisation) or adding nitrogen(thats probably what allen is talking about) or boron.
we are talking about carburisation tere are different methods pack the mild steel in case add coal seal the case and heat it up for a long time and the seel will get more carbon tis method is used to improve the quality of tamahagane,japanese sword steel, others methods use horn or other carbon rich materials . A more modern uses hydrogencarbonates like acetylen propan methan to produce a flame with not enough oxigen to burn all carbon. so these can build into the steel strukture.
the thickness of the surface wich is hardened can easily be up to multiple milimeters. the only problem is that you have to heat it up very high so that the steel tends to warp or loose the form. I dont know wich method they use. the low pressure method seems to be best carburisation from both sides rather low temperatures.But a vakuum chamber has to be used and
a lot of steps are needed to get a good result.

and now to james you have craftet very nice stuff.how much is a breast and backpleate out of your skilled hands.
and how did you case harden your early stuff .
yours stephan
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James Arlen Gillaspie
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Location: upstate NY
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PostPosted: Mon 04 Feb, 2008 2:04 pm    Post subject:         Reply with quote

Hello, Stephan,

I used to use a couple of different commercially available powders (which had different properties so I mixed them to get an optimal result) we have in the U.S. and heat the pieces with a large propane torch. Experience showed me about how long to heat and add powder. I quenched in water. A bit of tempering is good, but not to blue. It takes a couple of weeks for the plates to become optimal; apparently, the carbon is still finding its optimal place in the structure. Don't be dismayed if, when you take it out of the quench, nothing seems to have happened; this is actually a good thing. You have a half hour or so 'window' to take warps out of the piece before it starts to set.

What style of breast and backplate did you have in mind?

jamesarlen.com
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Stephan Hall




Location: Germany
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PostPosted: Wed 06 Feb, 2008 2:59 am    Post subject:         Reply with quote

James tell me if I´m wrong first you used case hardening to harden an armor.
but now you use spring steel or high carbon steel.
Next thing not that I could afford a B&B plate.(poor bastard I am) So I`m just curios
whats your basic price for a 15.th century milanese B&B(tempered steel ofcourse).
If you don`t wnt to post it in public send me a private mail
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James Arlen Gillaspie
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Location: upstate NY
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PostPosted: Fri 08 Feb, 2008 11:06 am    Post subject:         Reply with quote

Yes, Stephan, I started out with case-hardening. I would charge about $5000 for a tempered cuirass in the mid 15th century Italian style.
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Eric Forster





Joined: 07 Mar 2009

Posts: 10

PostPosted: Fri 03 Sep, 2010 10:36 am    Post subject: Old thread but I'll try to add something useful         Reply with quote

I've been corresponding with Milan at bestarmor concerning the construction of a helmet.

He said that, for no more than a 50% addition to the list cost for mild steel (actual markup is dependent on the helmet-type), he can do spring steel quenched to 50 HRc Rockwell.

Mild steel is 20-25 HRc, so it could be worth it to protect your head if you do heavy contact. 50 HRc is in the range of high-quality swords, if I remember correctly. I'm sure armorers and metallurgists on this site can comment on this hardness for a helmet.

Cheers,
Eric
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