MEMBER ITEMS FOR SALE
Custom Knives | Other Knives | General Items
-------------------------------------------
New Posts | New PhotosAll Photos



Go Back   The Knife Network Forums : Knife Making Discussions > Custom Knife Discussion Boards > Ed Caffrey's Workshop

Ed Caffrey's Workshop Talk to Ed Caffrey ... The Montana Bladesmith! Tips, tricks and more from an ABS Mastersmith.

Reply
 
Thread Tools Display Modes
  #1  
Old 02-05-2001, 09:25 PM
Clinker
Guest
 
Posts: n/a
Hardening & Tempering ?


Been reading some of the other post's.I have a few ?
Using spring steel 5160
1-Triple Quench- How long should you waite between each quench? Heat it right back up,or waite 24 hours between?
2- Triple Tempering- 350 in oven for 1 hour X 3?
3-Draw the back-After the triple temper should I draw the back with a torch? Should I do it 3 times also?
The last 4 knives I made triple tempered and triple draw on the back only quenched 1 time.They seem ok so far when I get some handles on them Ill see how they hold up.
Thanks for your help.albums.photopoint.com/j/V...0&res=high

Reply With Quote
  #2  
Old 02-05-2001, 11:03 PM
Ed Caffrey
Guest
 
Posts: n/a

#1. Leave the blades IN the oil after hardening, long enough for the blades to cool down WITH the oil to room temp. (5160 and 52100)
I usually do my hardening towards the end of the day, so that the blades cool in the oil at least overnight.

#2. Temper 2 hours X3

#3. If you edge quench there is not need to draw the spine. If your drawing the spine with a torch (which is incredibly tough to do correctly) then you only need do that if the blade was entirely hardened. I personally do not like, nor recommend drawing the spine with a torch. Often times the person doing it does not take the time to do it right, and causes more harm than good.
Remember, the triple quench is something that will bring better things out of 5160/52100. It has little or no improvement effects on plain carbon or steels that do not have that little bit of Cr in them. The best calculations and experements I have come up with, suggest that steels with less than 3% Cr derive the greatest benifits from the multiple heat treating methods. From spectrographs I have had done, blade that follow the triple pattern from normalizing, all the way can achieve grain structures of less than .5 microns, and 99.9% conversion to austinite. That's better than any of the commercial heat treater can even come close to. What this all means is that with care, you can heat treat your blades better than anyone else can do it for you.
There is one other thing........don't take my word for it, I always encourage folks to experiment for themselves, and find what works best for you. The items you hear me talk about are always the things that I have found work best for me, under the conditions in my shop. I never what it to appear that I think my way is the only way, it's not! It's just the best way that I have found. Hope this was of some help. :rollin:
Reply With Quote
  #3  
Old 02-06-2001, 02:16 AM
Kris M
Guest
 
Posts: n/a

Hello, Mr. Caffrey, for future reference(since I don't forge yet), I was wondering what type of oil you prefer for quenching 5160 and 52100, or if it makes much difference, and what temperature you heat it to? I was thinking different oils would have different cooling rates, and I know you have to cool steel to below a certain temperature(Ms temperature?) in a certain amount of time, that varies according to the steel being used, in order to get maximum transformation to martensite. I was wondering if the chromium in these steels cause them to need a different quench medium than plain carbon steels, because, as you pointed out in an earlier post, that seems to be what causes them to benefit from the multiple heat treat method.

Another question I have is, have you ever done any cryo-treating of your 52100 blades? I was looking back in some old Blade magazine issues, and saw an article by Wayne Goddard that showed a huge increase in wear resistance on cryo-treated 52100. I was wondering if the cryogenic treatment and the triple heat treat would achieve similar results.

Kris M
Reply With Quote
  #4  
Old 02-06-2001, 07:09 AM
Ed Caffrey
Guest
 
Posts: n/a

Hi Kris!
You bet! I routinely cryo my 52100 and 5160 blades. I didn't mention that in the above post, simply because sometimes that tends to put folks in "infromation overloade". Anyway, after my final tempering cycle I go to the liquid nitrogen, which adds 2-3 Rc points of hardness to the blade. I then temper one more time at 25 degrees higher than the previous tempering temp. The cryo is where the retained austinite gets transformed.

On the oil.....I've been using vet. grade mineral oil for several years for my 5160/52100 blades. It's more economics than anything. Standard quench oils can only be had in 50gal lots around here, and it's just too spendy to justify. I experimented with several different alternatives, and the mineral oil gave me all the results I was seeking, at around $7.50 per gallon. Compared to around $18 per gallon for arco brand light quenching oil. Just about any oil with a high flash point and viscosity of 10-15 will do well with 5160 or 52100. It's also useful for plain carbon steels. I keep four different quenches in the shop.....plain used motor oil for tools, hammers and such. "Super quench" for mild steel, ATF for plain carbons, and the mineral oil for 5160, 52100, and some damascus.
Reply With Quote
  #5  
Old 02-07-2001, 02:48 PM
Don Carter
Guest
 
Posts: n/a

Ed, have you played with clay coatings (similar to the Japanese makers) for differential hardening? I am specifically asking about the technique as I want to try it with a few knives (as soon as the forge is built), steel is L6 bandsaw blades/nickel foil damascus.

Your thoughts are as always appreciated.
Reply With Quote
  #6  
Old 02-07-2001, 04:07 PM
Clinker
Guest
 
Posts: n/a

Ed could you tell me the how to on drawing the spine with a torch (which is incredibly tough to do correctly)?What I did was to keep the edge in a pan of warter and heat the back of the blade.I thought that was the way to do it to keep the hardness in the edge.
Thanks
Reply With Quote
  #7  
Old 02-07-2001, 07:11 PM
Ed Caffrey
Guest
 
Posts: n/a

Don,
I use a retort for my clay coatings when creating a hamon on given blades, it works very well. With the way the heat transfers due to the clay, I don't consider it suitable for anything other than plain carbon steels in the 1045 to 1060 range. When used on higher carbon contents, there is a lot of austinite left over, in fact as much so that even a cryo won't get rid of enough of it to suit my tastes.

Clinker,
The actual heating of the spine is not the difficult part. And your correct to place the edge in water. The portion that messes up a blade is what most folks do after the spine has been drawn to the desired color(s).... most folks get in a hurry, and rush getting the colors in the spine. The only way to do it is SLOWLY, to the tune of taking 10-15min to get the colors on a hunter sized blade....... and once the chosen color is achieved, they then cool the blade down by dipping it in the water........MISTAKE! This is when the crystalization of the grain takes place, and all the time and effort that has been spent, is shot in that fatal second it takes to cool the blade in water. The only method I recommend is to leave the edge in the water, and allow the whole thing to cool down to at least a temp where it can be handled, bare handed. The most common mistake that occurs with heat treatment is a lack of patience. Everthing in a steels structure deals with time and temp in the correct combinations, to achieve a given end product. Some can never overcome the thing of "hurry up" and get it done. Each of us must choose the route we take, and the "trade offs" we are willing to accept. I choose to take the long road, even if it means a customer's order will be a bit later than planned. This all comes back to the fundamental fact that a person can spend 20 years building a good reputation in the knife world, and loose it in 10 seconds because of being in a hurry.
Reply With Quote
Reply

Tags
blade, forge, knife, knives


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

(View-All Members who have read this thread : 6
davidw, dmiller, dmoye, Gary Roberts, mike kinzell, RAPOZINHO
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -5. The time now is 04:17 AM.




KNIFENETWORK.COM
Copyright © 2000
? CKK Industries, Inc. ? All Rights Reserved
Powered by ...

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
The Knife Network : All Rights Reserved