Optimal hardness for 52100

Discuss Spyderco's products and history.
User avatar
sal
Member
Posts: 15911
Joined: Fri Sep 24, 2004 12:00 pm
Location: Golden, Colorado USA

Optimal hardness for 52100

Postby sal » Sat Aug 29, 2015 7:28 pm

Title says it. What are your thoughts?

sal

Ferris Wheels
Member
Posts: 750
Joined: Fri Apr 20, 2012 11:06 pm
Location: Denver, CO

Re: Optimal hardness for 52100

Postby Ferris Wheels » Sat Aug 29, 2015 8:19 pm

62RC in a thin, light, rounded spine 8" chef knife.

sbaker345
Member
Posts: 310
Joined: Sun Feb 02, 2014 1:32 pm

Re: Optimal hardness for 52100

Postby sbaker345 » Sat Aug 29, 2015 8:35 pm

I agree, 62RC+/-, it would be a waste if the steel was too soft to take a keen acute edge, and its not prone to massive chipping.

User avatar
Archimedes
Member
Posts: 665
Joined: Fri Feb 20, 2015 2:39 pm
Location: Nor Cal

Re: Optimal hardness for 52100

Postby Archimedes » Sat Aug 29, 2015 8:50 pm

Run it up to the high 60's. 68-69. Push the steel a little.

User avatar
SpyderNut
Member
Posts: 8337
Joined: Fri Sep 24, 2004 10:33 am
Location: Hoosier Country, USA
Contact:

Re: Optimal hardness for 52100

Postby SpyderNut » Sat Aug 29, 2015 9:10 pm

Archimedes wrote:Run it up to the high 60's. 68-69. Push the steel a little.
Wouldn't that make it too brittle though? I almost think that 64--66 would be a better compromise.
:spyder: -Michael

"...as I said before, 'the edge is a wondrous thing', [but] in all of it's qualities, it is still a ghost." - sal

User avatar
The Mastiff
Member
Posts: 5792
Joined: Sun Jun 04, 2006 2:53 am
Location: raleigh nc

Re: Optimal hardness for 52100

Postby The Mastiff » Sat Aug 29, 2015 9:13 pm

In a folder or smallish fixed blade I'd say there are good reasons to try rc 61 ( rc 60-63). IMO, there is a lot of performance gained going from rc 58 up to rc 61. With this steel one needs a bit higher hardness to get the steel to really perform. Depending on how things are done it can go higher or lower and still have good performance but for me I'd go for the sweet spot when I could unless there was a reason not to.

If I needed higher hardness than rc 62 I'd probably try a different alloy.

Thanks for giving this serious consideration. It's one of my favorites and I tune in every time I see it being discussed.

Joe

Cliff Stamp
Member
Posts: 3852
Joined: Sat Dec 31, 2005 2:23 pm
Location: Earth
Contact:

Re: Optimal hardness for 52100

Postby Cliff Stamp » Sat Aug 29, 2015 9:24 pm

Archimedes wrote:Run it up to the high 60's. 68-69. Push the steel a little.
It would take some pretty demanding cycles to get 69 HRC in 52100.

Cliff Stamp
Member
Posts: 3852
Joined: Sat Dec 31, 2005 2:23 pm
Location: Earth
Contact:

Re: Optimal hardness for 52100

Postby Cliff Stamp » Sat Aug 29, 2015 9:30 pm

sal wrote:Title says it. What are your thoughts?
Don't use hardness as a means to judge how to harden steel.

--

There are a few general ways to approach it based on what you are trying to achieve :

-If you want a balance of strength/toughness/wear resistance then soak just enough to put ~0.6% carbon in solution, leave most of the chromium undissolved, use an agitated oil quench to ensure minimal diffusion, cryogenics (if possible), to reduce retained austenite, and then temper ~350 F to 400F to get the plastic zone you want. Joe Calton has a video recently where he shows a very simple check you can do to estimate the start and extent of the plastic zone with very basic materials.

-If you want a very high toughness/durability then reduce the soak time a little, don't use cryogenics, and temper just in front of the 500F embrittlement zone. This will give a blade with a much wider plastic zone but a reduced strength and wear resistance.

-If you don't care much about toughness then soak a little hotter/longer, it is critical to use cryogenics as the retained austenite will be very high, and temper low, 325-350F. This gives the highest strength and wear resistance but you won't have much plastic deformation at all.

There are guys on HypeFree who have the exact cycles on each one of these and have described how they behave in terms of rope cut and flex and impact tests. Most people tend to do the first one because it tends to have decent performance over a broad range of tasks and users.

ohcyclist
Member
Posts: 494
Joined: Mon May 20, 2013 11:25 pm

Re: Optimal hardness for 52100

Postby ohcyclist » Sat Aug 29, 2015 9:42 pm

Ferris Wheels wrote:62RC in a thin, light, rounded spine 8" chef knife.
This would be fantastic. Even better if you pair it with a nice micarta handle a la the temperance two but polished.

On a more serious note I would vote just over 60. I have a couple of kitchen knives in this steel and they are fantastic.

A question I should have asked before giving an opinion: what type of blade do you have in mind?

Final slightly off topic comment, what about the kiwi 4 in this steel? Polished g10 and non ambidextrous wire deep carry pocket clip.

User avatar
Mic1
Member
Posts: 479
Joined: Thu Jul 16, 2015 9:17 am

Re: Optimal hardness for 52100

Postby Mic1 » Sat Aug 29, 2015 9:59 pm

MS J Neilson who makes all my fixed blades out of 52100 just sent me a text 58-59. Same for MS Bill Burke and MS Ed fowler I believe don't quote me on that . Both Burke and Fowler have study 52100 for knife use more than anyone I bet .In practical application and scientific methods like metallurgy. Either MS Fowler Or Burke would be a great wealth of knowledge. I bet they would be more than happy to take your call Sal. If not I know J. would no problem he is a great guy easy going knows his business and does not mind sharing his knowledge and experience.
Last edited by Mic1 on Sat Aug 29, 2015 11:20 pm, edited 1 time in total.

User avatar
Ankerson
Member
Posts: 6570
Joined: Sat Jul 24, 2010 1:23 pm
Location: Raleigh, NC

Re: Optimal hardness for 52100

Postby Ankerson » Sat Aug 29, 2015 10:57 pm

sal wrote:Title says it. What are your thoughts?

sal
Hi Sal,

I would have to ask optimal for what type of knife? :)

As optimal for a slicer would be much different than optimal for a chopper and both would be different than optimal for something in the middle as in all around use.

For a Kitchen knife that is thin I would say around 63-64 range.

For a Slicer, smaller fixed blade 4" to 5" or so something in the 62-64 range depending on exact geometry.

For a folder I would say 61-62 with more normal geometry, maybe slightly thinner than normal in the .015" range or so.

For larger fixed blades or choppers, hunting knives etc that will see harder use something around 58-61 max depending on what the knife is exactly.

All of that is taking into count the production process and not heat treating one or two knives at a time.

All of this is just my opinion based on what I have seen over time, geometry would have a large impact on what the final hardness ranges were as would the actual use based on the design of the knives.

The actual HT process is going to vary greatly depending on what the actual needs of the end product will be and how the testing goes to narrow it down. So without knowing what you have in mind I am just shooting from the hip at this point.

Jim

User avatar
anagarika
Member
Posts: 1687
Joined: Sun Jul 15, 2012 5:59 pm

Re: Optimal hardness for 52100

Postby anagarika » Sun Aug 30, 2015 12:50 am

I have bluntcut's slicer @ 62-63 HRC. He knows his 52100. Meanest yet smoothest cutter and even shave (dry face stubble) with no irritation.

My hope is going up seeing this being asked :D
Chris :spyder:

elena86
Member
Posts: 3260
Joined: Fri Sep 03, 2010 6:59 am
Location: Somewhere in Europe

Re: Optimal hardness for 52100

Postby elena86 » Sun Aug 30, 2015 3:40 am

Don't push it ; 61-63 HRC is my bet.I hope for a FFG folder since not everyone need a chef knife or a fixed blade.But don't go beyond 63HRC.

Cujobob
Member
Posts: 844
Joined: Sat Aug 31, 2013 9:26 pm

Re: Optimal hardness for 52100

Postby Cujobob » Sun Aug 30, 2015 5:42 am

62-63 for a folder. Optimizing for toughness given the purpose behind most of Spyderco's knives doesn't make much sense to me. I've seen this steel likened to AEB-L/14C28N (different steels but similar) and that steel is far better optimized at 62 rc vs 59-60 as far as a balance of toughness and edge retention IMO.

User avatar
sal
Member
Posts: 15911
Joined: Fri Sep 24, 2004 12:00 pm
Location: Golden, Colorado USA

Re: Optimal hardness for 52100

Postby sal » Sun Aug 30, 2015 12:00 pm

Thanx for the input. I told Annika to make them 62-63, but I thought to check with my "consultant steel junky's".

Thanx for the input Cliff. Our heat treater is a metallurgist. I'll share your info with him.

I plan to put it in a Millie Jim. Mostly because I wanted one in 52100 as a work knife on the mountain. I figured you and Joe would probably want one as well. So we have 3. We'll make 1000. It was a real PITA to find it rolled to the thickness wanted. It's also a bugger to work with in a production environment. Not too many production folders out there in 52100. I can see why.

sal

User avatar
Ankerson
Member
Posts: 6570
Joined: Sat Jul 24, 2010 1:23 pm
Location: Raleigh, NC

Re: Optimal hardness for 52100

Postby Ankerson » Sun Aug 30, 2015 12:05 pm

sal wrote:Thanx for the input. I told Annika to make them 62-63, but I thought to check with my "consultant steel junky's".

Thanx for the input Cliff. Our heat treater is a metallurgist. I'll share your info with him.

I plan to put it in a Millie Jim. Mostly because I wanted one in 52100 as a work knife on the mountain. I figured you and Joe would probably want one as well. So we have 3. We'll make 1000. It was a real PITA to find it rolled to the thickness wanted. It's also a bugger to work with in a production environment. Not too many production folders out there in 52100. I can see why.

sal

Hi Sal,

Yes, I figured it would be a PITA to work with due to various reasons. :D

Oh yeah, you have that pegged, I think Joe would love one and I would as well, love 52100 personally, that and A2. :cool:

Jim

elena86
Member
Posts: 3260
Joined: Fri Sep 03, 2010 6:59 am
Location: Somewhere in Europe

Re: Optimal hardness for 52100

Postby elena86 » Sun Aug 30, 2015 12:10 pm

sal wrote:Thanx for the input. I told Annika to make them 62-63, but I thought to check with my "consultant steel junky's".

Thanx for the input Cliff. Our heat treater is a metallurgist. I'll share your info with him.

I plan to put it in a Millie Jim. Mostly because I wanted one in 52100 as a work knife on the mountain. I figured you and Joe would probably want one as well. So we have 3. We'll make 1000. It was a real PITA to find it rolled to the thickness wanted. It's also a bugger to work with in a production environment. Not too many production folders out there in 52100. I can see why.

sal
Count me in Sal.So we are 4 and counting :)

User avatar
Johnnie1801
Member
Posts: 2219
Joined: Sat Apr 26, 2014 10:29 am
Location: Europe

Re: Optimal hardness for 52100

Postby Johnnie1801 » Sun Aug 30, 2015 12:15 pm

elena86 wrote:
Count me in Sal.So we are 4 and counting :)
Make that 5 :D

I really hope to get one, love the Millie :D
Currently enjoying Spyderco's in - S30V, VG10, Super Blue, Cruwear x4, CTS XHP, S110V x2, M4 x3, S35VN, CTS 204P x2, S90V, HAP 40, K390, RWL34, MAXAMET, ZDP 189, REX 45


Jon

User avatar
bearfacedkiller
Member
Posts: 11227
Joined: Sat Jan 04, 2014 1:22 pm
Location: hiding in the woods...

Re: Optimal hardness for 52100

Postby bearfacedkiller » Sun Aug 30, 2015 12:18 pm

What was the mule run at? I have the 52100 mule and am happy with it's performance. I have used it mostly in the kitchen though. I always grab the s110v or m4 mule for hunting and fishing.

You can count me in on a 52100 Military. Sounds great. There was talk of making a 52100 UKPK, I wonder if that is still in the works?
-Darby
sal wrote:Knife afi's are pretty far out, steel junky's more so, but "edge junky's" are just nuts. :p
SpyderEdgeForever wrote: Also, do you think a kangaroo would eat a bowl of spagetti with sauce if someone offered it to them?

User avatar
Ankerson
Member
Posts: 6570
Joined: Sat Jul 24, 2010 1:23 pm
Location: Raleigh, NC

Re: Optimal hardness for 52100

Postby Ankerson » Sun Aug 30, 2015 12:34 pm

I wonder what color G10 they are going to be?

A multicolor would be nice I think, maybe black and red. :D :cool:

Would look nice with the patina that 52100 will have in time.


Return to “Spyderco General Discussion”

Who is online

Users browsing this forum: Araignee, Bdubs808, Bing [Bot], Google [Bot] and 46 guests