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 > Knife Making Discussions > Heat Treating and Metallurgy

Heat Treating and Metallurgy Discussion of heat treatment and metallurgy in knife making.

Reply
 
Thread Tools Display Modes
  #46  
Old 02-04-2016, 12:29 PM
Doug Lester Doug Lester is offline
Hall of Famer
 
Join Date: Sep 2006
Location: Decatur, IL
Posts: 2,482
As long as your blade does not get over 1500 you should be fine as far a grain growth goes. Going over 1475 may cause too much carbon to go into solution and increase retained austenite. HOWEVER, even that can be corrected for with repeated tempering cycles. Fun, isn't it?

Doug


__________________
If you're not making mistakes then you're not trying hard enough
Reply With Quote
  #47  
Old 02-04-2016, 04:30 PM
David Eye David Eye is offline
Enthusiast
 
Join Date: Dec 2015
Location: North Central WI, USA
Posts: 74
Thanks Doug, yes it will be fun and I'm getting anxious to build my kiln and get going on things.
I will take every precaution that my blades don't get over 1475F, give or take a few degrees.
I will definitely make sure my kiln is well stabilized first and my controller and TC will be of high quality too.

The way I am going to heat my blades in my elect kiln is exactly what many experienced people are doing, I believe some guys on this forum and many on another forum. A slightly longer soak actually accomplishes the same thing....please read on.
Basically, the method they are using that I described is just making sure the 1095 blade is actually up to set temp of 1475F BEFORE the timed soak. This equates to approx. the same amount of timed soak of no more than 10 minutes @1475F. It just takes approx. 4 minutes for the knife to actually first get up to 1475F.
Technically, the timed soak of no more than 10 minutes is NOT supposed to commence until the blade is actually at 1475F.

If I'm not mistaken, it's basically the same as Stuart described of putting the blade in when the kiln is stabilized at 1475F and waiting for the kiln to "rebound" to 1475F because he said it probably takes just a few minutes or so for that to happen anyway. He then did the timed soak after the kiln rebounded.
Soooo.... after my kiln is stabilized at 1475F for awhile, I will then introduce my blade to the kiln and have it in there for exactly 4 minutes (the kiln MAY or MAY NOT rebound in slightly less than 4 minutes, but the BLADE NEEDS 4 MINUTES to get to temp according to testing)......and then I will do the 5-10 minute soak. At no time should the blade get over 1475F if all goes well with my equipment. The average of 4 minutes for the blade to actually get up to 1475F was proven by extensive testing and I guess I am going to believe that based on their methods of testing.
I can always shorten the actual timed soak a little if need be.
I am planning on about 8 minutes of timed soak since I my research found that a soak of 5-10 minutes @1475F for 1095 was plenty.

As an added note, one individual on the thread I mentioned I found on another forum stated that you can help avoid temp overshoot by putting the elect kiln in some kind of "idle mode" during rebound when you put the knife in. This apparently keeps the heating elements from coming on right away, or too much or even at all....I'm not sure. This method will supposedly use residual kiln heat for a short time until you tell the controller to proceed to original set temp of 1475F.
I would gladly refer anyone interested to read said thread/posts on the other forum either right here or by PM, but ONLY if the moderator here gives me permission.
DAVID

Last edited by David Eye; 02-04-2016 at 06:10 PM. Reason: Important addition versus new post.
Reply With Quote
  #48  
Old 02-08-2016, 08:26 PM
mstrick96 mstrick96 is offline
 
Join Date: Jan 2011
Posts: 3
This is a fascinating thread. I am also planning to heat treat 1095 had similar questions, and the discussion has helped a lot.

I have already built an electric kiln and it works great. It should go to about 2200 degrees F, possibly higher, but I have only taken it to 2000.

My question that I think will add to this thread is concerning canola oil as a quenchant. The commercial quenchants generally publish the GM Magnetic Quenchometer speed numbers and the quenchants are grouped into fast, medium and slow speed ranges. It seems that the recommended quenching speed for 1095 is in the 7 to 8 second range or so.

What are the quenchometer quenching speeds for brine, water, canola, oil, etc? I have found some relative quenching speeds that were normalized with water at "1" and the rest proportioned to that, but have not seen actual quenchometer values?

MikeS
Reply With Quote
  #49  
Old 02-09-2016, 12:19 AM
Doug Lester Doug Lester is offline
Hall of Famer
 
Join Date: Sep 2006
Location: Decatur, IL
Posts: 2,482
I don't know if there is any equivalent data for canola oil. There may be for water an brine but I don't have the data for that if it exists. Be aware that not all 1095 out there is made equal. Some of it has less manganese that others and will require a faster quench. Ideally, you would have an HRc tester to test the as quenched steel. Baring that, you could check hardness by seeing if a sharp file will bite into the steel. If you tried to quench with canola, for instance, and it came out too soft on the tester or the file bit into the edge of the blade then you will have to step things up a notch. You could either suck it up and buy about five gallons of a fast quench commercial oil or go to brine. I wouldn't recommend water as it forms a bad vapor jacket around the cooling steel that can lead to warping or breaking. Still even with brine you will need to reduce all the stress raisers that you can.

Doug

Instead of retyping this whole thing I'll just post a correction to the above. If you have an HRc tester you will probably not be able to test 1095 at the ricasso on all but the thinnest blades, 1/8" thickness or less. You will have to make a coupon no thicker than that, and a little thinner won't hurt, and run it through the hardening procedure and test it on the machine. A piece of steel over around 1/8" may be too thick to harden depending on the size of the grain. A file on the edge of the blade should just about always work.


__________________
If you're not making mistakes then you're not trying hard enough

Last edited by Doug Lester; 02-09-2016 at 12:27 AM.
Reply With Quote
  #50  
Old 02-09-2016, 10:56 AM
mstrick96 mstrick96 is offline
 
Join Date: Jan 2011
Posts: 3
Thanks! This is helpful.

I haven't found much information on the GM Quenchometer on the forum. I'll look some more and if I still can't find anything, I might try to start a thread on it.
Reply With Quote
  #51  
Old 02-09-2016, 10:57 AM
samuraistuart samuraistuart is offline
Steel Addict
 
Join Date: Dec 2012
Location: San Antonio Texas
Posts: 134
Parks 50, as we know is a "fast" oil, has a nickel ball speed of 7 seconds.
AAA has a nickel ball speed of 9-11 seconds.
Quench K has a nickel ball speed of 7-9 seconds.
Canola oil at 130f is said to have a speed of around 9 seconds.

I can't seem to find any info giving nickel ball speed of water or brine.

I did find a chart that showed that a 10% brine solution has twice the cooling rate of water.

I figured I should edit this to add to that comment about brine/water.....I don't think that brine is actually TWICE as fast as water, but that the salt helps to break down the vapor jacket.....so in essence you get a faster quench rate.

Last edited by samuraistuart; 02-10-2016 at 10:30 AM.
Reply With Quote
Reply

Tags
1084, 1095, art, awesome, bee, blades, building, carbon, cold, degrees, first time, forge, forged, grinding, hand, heat, heat treat, hot, knife, knife making, make, making, newbie, sand, temper


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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Liner lock break in procedure ? Dave Kelly The Folding Knife Forum 7 10-10-2003 04:07 PM
A few questions??? Jeremy Krammes Knife Making Discussions 3 03-22-2003 10:31 AM
hello and three questions for you... PDCarby Knife Making Discussions 2 10-31-2002 12:46 PM
procedure for freezing blade Navajas The Newbies Arena 6 08-27-2001 04:32 AM
Normalizing procedure gthomas Ed Caffrey's Workshop 5 02-06-2001 06:06 AM


All times are GMT -5. The time now is 07:29 PM.




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

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
The Knife Network : All Rights Reserved