1095 question

Larry Hensley

Larry Hensley

Joined
Dec 31, 2007
Messages
420
Ok this is going to be the mother of all stupid questions. (And i get to ask it HAHA)

when I look at the admiral steel price sheet and order line there are two different classifications of 1095. HR1095 and CRA1095, what are the differences and is one better for forging and one better for Stock removal?

And if so which is which?

Larry
 
HR stand for Hot Rolled and CR stands for Cold Rolled. Hot rolled is great for forging while the cold rolled is great for both. The cold rolled has a much nicer finish to the surface of the steel and no millscale. While with HR you need to grind the scale off.
 
Talking as a machinist here, not a knife maker,

Cold rolled steel is more accurate, has square corners and looks nice, but tends to have more rolled in stress. This means that long sections of it tends to warp if you cut or grind on it. It also can have "junk" rolled into the surface of it. It can also have an alligator tread kind of imperfection that goes pretty deep and shows when polished or etched. It costs more.

Hot rolled pickled and oiled (HRPO) is hot roll with the scaled removed. I'm kind of partial to it.
 
Nathan the Machinist said:
Talking as a machinist here, not a knife maker,

Cold rolled steel is more accurate, has square corners and looks nice, but tends to have more rolled in stress. This means that long sections of it tends to warp if you cut or grind on it. It also can have "junk" rolled into the surface of it. It can also have an alligator tread kind of imperfection that goes pretty deep and shows when polished or etched. It costs more.

Hot rolled pickled and oiled (HRPO) is hot roll with the scaled removed. I'm kind of partial to it.
Click to expand...

Ok you lost me with Pickled and oiled LOL I have not heard that term
 
Here's a question on cold rolling. Will the rolling cause the steel to work harden?
Click to expand...

Yep that's why the "A"

Also Chuck, sorry I wasn't trying to bust you chops or anything like that just figured someone would ask.
 
I have bought plenty of HR 1095 from Admiral and none had any scaling or outter coating? Grinds very easy also.
 
I got some cold rolled 1095 from Kelly Cupples a few years back that was nearly mirror finished! It was gorgeous... I couldn't bring myself to mess it up in the forge ;) so I did a stock removal blade or three out of it :eek: :D

It actually had super nice radiused edges as well.

Can't really add anything that hasn't been said already.
 
It helps to think of this question in terms of the flow of the steel through the production process. HR (Hot Rolled) is taking the metal from a large hot ingot into basic dimensions. If you guage the thickness of several pieces of hot rolled steel with a set of calipers or a mic you will see a pretty good size variation in thickness (I've measured up to 30 thousanths oversize). The edges typically tend to be sheared as well. Watch out for that because I've cut myself on burrs before. Alot of scale can be included as well. At this stage of the game, processing isn't very uniform. One may get a piece of steel that is very good dimensionally and have little scale or the exact opposite. For forging, HR is just fine.

CRA on the other hand has more and finer processing (a second stage of processing). The metal is allowed to cool quite a bit before it is put back through the rollers. This allows it to be less squishy (if you will) and a tighter tolerance can be held. CRA is within +- 10 thousanths of an inch (easy) and of course this applies to both thickness and width. The colder working temperature (going through the rollers) tends to work harden the material, as a result it needs to be annealed (done at the factory hence the name cold rolled annealed) so that anyone who puts a cutter to it has a good day instead of having the tips of their endmill trashed. For those who are looking for a piece of material which is more consistent dimensionally this would be the ticket. Oh, and by the way, the higher price paid for CRA is directly related to this "higher degree" of processing.
 
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