1080 steel HT

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how does everyone do their Heat treat for 1080? Im trying to see what ill need if i decide to go with this as my first real steel. thanks again guys for helping me out!
 
Hey Hurley, welcome to the forums and good choice for a steel. This is my way of Hting 1080, I heat it up 1500 and quench into a fast oil and temper for 1 hour and 30 minutes twice, I also clay coat mine to bring out a hamon. Before I had a thermocouple I would heat until a magnete wouldnt stick and then put it back in the forge for 5 to 10 seconds then quench in a fast oil. If you quench it to hot the edge will be brittle when you begin to sharpen it. Its a fairly easy metal to learn, and should serve you well, Hope I helped alittle,Charlie Edmondson
 
Hurley,

Howdy, I was instructed by 'Masterbladesmith Dan' to
'bring the blade to non-magnetic and quench.'

Now, there's more to it than that.
Non-magnetic is not that hot and you don't want to over heat.
Get a good magnet handy,
{mine is stuck to the iron table the forge itself is resting on.}
Hold the blade with your tongs and don't lay it down.
Non-magnetic is between red and 'barely orange'.
Check the blade often, count...
2-3 seconds and test the magniticity.
2-3 seconds and test the magniticity.
"
"
When non-magniticity is reached...
See... you have to be aware how hot this blade is all the time.
A thin steel like I use, 1/16" must be quenched in UNDER! a second.
But be aware by counting where your blade is in relation to magnetism.
If it is still magnetic... keep heating.
If it is not magnetic...
it still may be too late to quench
if you messed around too long with the magnet.
A second more in the fire and then quench.
I quench in used motor oil with 20% transmission fluid in it.
{It can burst into flames so keep a piece of plywood cut to size to cover your quench bucket}
{The fumes stink and are bad for you so keep a fan blowing}
Temper in an oven for 2 hours at 400 degrees.
{I have a little electric oven to temper outside}
{and don't temper in 'My Oven'}

Now, I am just practising giving heat treating advice
I don't know what I am doing,
as I am just learning this 'heat treating stuff myself.'
{or trying to}
Like most things I have learned in my life,
'It's easy if you know how.'
Hmmm...


Good luck...


J. Knife
http://jacksknifeshop.tripod.com/
 
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Hurley,
1080 is eutectoid steel - It has the simplest HT. You need to heat it evenly ( avoid overheating the edge) to 1500F and quench as soon as the blade is at that temperature. No need to soak ( hold at austinitization temp) for any length of time. Quench in fast oil, like parks #50,. Water or brine will work, but blades can crack or warp much more likely. Temper twice at 450F. This will give you a hard and tough blade.

Read Kevin Cashen's post at the top of the page "Working with three steels". The entire process is explained.

My advise would be to avoid blends of old motor oil and ATF. It will work for many steels, but for shallow hardening steels, it may be less than optimal. Buying a gallon or two of proper quench oil will be a good investment.
1080,1084,1095, W1, W2 all need fast quench oil.
1070 and below often need water or brine to quench them.
O-1, L-6, 5160, S7, and other high alloy steels need a medium speed oil quench.
A-2. D-2,and stainless steels are air quenched, often using quench plates to avoid warping.

You will hear and read a lot of conflicting info about HT procedures. One advantage of 1080/1084 is that most all of those procedures will work for it. The one critical step is the quench. Assuming the steel is about the right temperature, the quench is where the austinite ( what forms above non-magnetic) converts into martensite ( what we want for a knife blade). Cooled too fast...it cracks or warps, cooled too slow...the blade is too soft or only partially hardened. Most blade steels between 1080 and W2 ( from .80% to 1.00% carbon) have only about one second to lower the steel temperature from 1500F to below 900F. That is what the words "fast", "medium", and "slow" mean in quench oil ratings.

As to using a magnet to determine the blade temperature....it is a good system. At about 1300F the steel changes from one structure to another. It looks the same, but the new structure is not magnetic. Checking the steel by using a magnet ( the cheap telescopic pick-up magnets work well) as the blade heats up will tell you when this change occurs. At this point it is not ready to quench ( even though many will tell you to quench then). It has to heat up about 150-200 degrees more. You observe the color at non-magnetic, and heat it up a shade or two brighter. That should put you in the ball park. The things you want to do are keep the blade moving and turning, so the thicker spine and the thinner edge are as near the same temperature as possible. Avoid overheating the edge...that the part you are going to use in cutting.

Once the blade is at the austinitization temperature, quench in a smooth and even plunge into a gallon or more of the proper quenchant. Quench straight in, point first. Only move the blade up and down, or in a cutting motion from spine to edge. Avoid moving it from side to side or it may warp. After about 7-10 seconds, pull the blade out and check it for warps. If it has some warp or twist, immediately straighten them with gloved hands or on a 2X6 with a wooden mallet. You have until the blade cools to 400F to do any straightening. At 400F the steel converts into martensite, and will become very hard and very brittle. Do not attempt to straighten any more. Allow to cool to room temperature, wash off the oil, and as soon as possible , place in the oven at 400-450F to temper for one to two hours. Take out and let cool to room temp and put back in the oven for a second temper cycle. Now your blade is hard and tough.

There is a lot more to HT than this, but that is a basic starter procedure. Again, reading Kevin's posts will provide a lot more detail.

Stacy
 
Second what Stacy said
non-magnetic is not hot enough anyone who tells you that it is does not know what they are talking about.
If you cannot afford real quenching oil (recommended) a less dangerous alternative to the motor oil/ATF mixture is olive oil heated to 130f it will work but not as well as real quenchant and it will not flashfire like the petroleum oils

Read the stickies and be safe

-Page
 
i know its not proper but would a veggie oil work?

For 1080? Not especially well. This steel needs a fast oil and vegetable oil (despite its popularity) is not a very fast quench.

Look at McMaster part number 3202K4. $15.00 buys you a gallon of relatively fast quench oil that will work for 1080.

How much does a gallon of vegetable oil cost? :rolleyes:
 
'Blad' dude,

The best... and most clearly written explanation.


Thank you...

"As to using a magnet to determine the blade temperature....it is a good system. At about 1300F the steel changes from one structure to another. It looks the same, but the new structure is not magnetic. Checking the steel by using a magnet ( the cheap telescopic pick-up magnets work well) as the blade heats up will tell you when this change occurs. At this point it is not ready to quench ( even though many will tell you to quench then). It has to heat up about 150-200 degrees more. You observe the color at non-magnetic, and heat it up a shade or two brighter. That should put you in the ball park. The things you want to do are keep the blade moving and turning, so the thicker spine and the thinner edge are as near the same temperature as possible. Avoid overheating the edge...that the part you are going to use in cutting."



Blad,

One point... edge?

I was told... "no edge" as the 'edge' heats up way to fast.
'Out of proportion to the rest of the blade.'
And do not grind, even a 'rudamental edge' before heat treating,
unless you are making 'Big Swords...!!!'
What degree of edge is appropriate?
My steel is 1/16' & 1/8'...
{real thin}


Thank you...
{lets git ignert and go coon hunting!}


J. Knife
 
Nathan DO you know what quench oil this is? I have been using Brownells tough quench, but 40 bucks a gallon is choking me right now!

For 1080? Not especially well. This steel needs a fast oil and vegetable oil (despite its popularity) is not a very fast quench.

Look at McMaster part number 3202K4. $15.00 buys you a gallon of relatively fast quench oil that will work for 1080.


How much does a gallon of vegetable oil cost? :rolleyes:
 
Nathan DO you know what quench oil this is? I have been using Brownells tough quench, but 40 bucks a gallon is choking me right now!

Yeah. It is "Super Brand" Quenchfast Quenching Oil. "Recommended for applications where very fast quench times are needed". It isn't Parks 50 - but it is going to be a better bet than any vegetable oil.
 
You were given the right advise. The "edge" should be flat, never sharpened, prior to HT. With carbon steel, like 1080, the edge on a knife before HT should be no finer than .040". That is about the thickness of a dime. If using 1/16" stock ( .065") most makers just profile the knife, harden the blade, and grind the bevels and edge after HT.

Stacy
 
Warm canola oil works too with 1084. This is not 1095, it does not have to be quenched quite as fast. The fast oil actually gave me some warping. I also tried the even faster water quench (to dull red) and quenched the rest in r.t. oil., that also works but also warps. I never got any cracking. A full water quench might crack it, never tried.
 
It always pays to mention this, and only because I've seen or heard of it being done more than once... Bring the steel out to the magnet to check it. Although the telescopic magnets do work well for this, resist the urge to stick them in the oven/forge... Some breeds of neodymium magnets can start to permanently lose their magnetism at around 300°...

-Eric
 
This thread is almost 5 years old.

There is some information that I gave above that was correct to my knowledge at the time, but since that time it has come to our attention that warm canola oil actually does a pretty good job. It isn't ideal because the quench properties are not controlled and it does go bad, but apparently the quench speed of canola oil is suitable for most of the fast quench steels.

I prefer an engineered oil because it doesn't really cost any extra and it is designed for the job and the properties are known and consistent, but when I said that a vegetable oil wouldn't work for this application I was wrong.
 
Nathan, thanks for clearing that up. It really is amazing how "what we know" changes over time.

John, In the same vein as my comment above... "I've always heard" that the IR thermometers aren't accurate enough for our needs. Maybe that's changed as well?
 
This thread is almost 5 years old.

There is some information that I gave above that was correct to my knowledge at the time, but since that time it has come to our attention that warm canola oil actually does a pretty good job. It isn't ideal because the quench properties are not controlled and it does go bad, but apparently the quench speed of canola oil is suitable for most of the fast quench steels.

I prefer an engineered oil because it doesn't really cost any extra and it is designed for the job and the properties are known and consistent, but when I said that a vegetable oil wouldn't work for this application I was wrong.

I figured somebody would comment on me reviving this thread, I've never worked with those steels but took on a heat treating project involving 1080/1084. I googgled it and this thread came up. Pretty cool all the info on here, so, I subscribed so I wouldn't lose the info.....:thumbup:
 
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