Heat Treating for a Hamon?

theWeatherman

Well-Known Member
I was wondering what you guys thought about taking 1084, W2, and heat treating for a hamon with a torch.

My plan is to take the two steels and use clay to coat. Let dry over night. Then to use a torch to do the heat treating. Take the metal to non magnetic and get the wet look and then quench in fast quench oil. My idea is that the clay would allow for the pattern to show instead of just a strait line, which you would get if you did not use clay.

I figure that if the old sword makers can do it in a forge and use the colors for a heat template then if done correctly it would be possible to get a similar outcome with a torch.
 
As long as you can get an even heat without overheating, you should be able to do it with a torch. You will find the W2 gets the better looking hamon of the two, the higher manganese in the 1084 causes it not to respond quite as well.
 
even heating is very important. With w2, so is the ability to soak it for at least a minute or so at temp prior to quenching. I would suggest making a charcoal forge with an air blast. Just dig a trench and put a pipe with holes in the bottom. Make a way to put a hair dryer blowing into the end of the pipe with a reducer or soup can and duct tape. block the far end of the pipe with a cap or whatever way you choose.

buy some real hardwood charcoal and break it into chunks about 1" cubed. Light a bunch of charcoal using one of those chimney starters, pour it over your new tuyere (the pipe with holes about 1 per 3/4" or so), and add more. To heat treat, you want the tuyere to be in a smaller trench just below the main trench. The depression with the pipe is about 1" deeper than the pipe is in diameter, and just wide enough to hold the pipe. The pipe section with the holes is about 4" longer on each end than the longest blade you plan to heat treat (I had a 44" pipe and used it for years. You can just cover the holes you don't need with duct tape). The main trench widens out to about 10" wide or a little less with straight walls. Make it about 6" from bottom of main trench to top of walls. You can pile charcoal higher if needed by putting firebrick along each side of the trench. You shouldn't need it unless you want to make orishigane or heat treat in the snow (I have done that, actually).

voilla ... a heat treating forge that will provide an even heat and allow you to control temperature by regulating air blast. Costs almost nothing. Put the blade into the pile of charcoal so that there is about 3" or more under it and 2" on top of it. Don't put it right next to the air blast. Move the blade back and forth a few inches at a time to keep the heat even. play with it. This will work better than anything except a propane forge or a kiln.

kc
 
Oh well, I guess I won't be trying to get any 1084 from Aldo, at least until he gets some more in. I might give AKS's 1080+ a try. Anyway, I saw some people at a hammer-in two years ago try out some of his 1095 and they were getting good hamons with it. It's also was formulated to heat treat well without the problems others have experienced with 1095 from other suppliers. Happy forging and I'll be looking forward to you posting some finished products or even WIP photos.

Doug
 
Hey Doug,

Aldo just didn't have any sizes that I needed he might have something though. I was saying he was taking a lot of stuff to Blade.

If I get the results that I am looking for I will definitely make a WIP and take pictures.
 
Thanks for the feed back. Even if you don't get the results that you want put up some WIP and finished photos. Maybe we could help you understand what happened, or didn't happen. Anyway, seeing pictures of other people's mistakes doesn't make us feel so dumb.

Doug
 
hey - the suggestion with torch to try and use Aldo's low manganese 1075 is a very good one. The bowie I posted in the neo-tribal area is that steel. It made a great hamon, and you don't have to soak it. Just get it up to nonmagnetic and even.
kc
 
This is all good info but I need to take this into a different direction, now. I did a lot of searching and I found a change in process for Heat Treating the 1095 in the past 3-4 years.

From what HAS NOT CHANGED:

1)1095 is hard to harden correctly. However, people say that the Aldo 1095 is pretty good, so that makes me feel better.
2) Need fast quenching oil (Parks #50)
3) Lots of post saying that 1095 is really hard to HT, and is persnicerdy.

What has changed is"
1) Temp ranges are from like 1475 degree F to 1550 degree F? (I am still going to use a torch but this is still good to know)
2) Warm Parks #50 to 130 degree F or leave at room temp? (I have seen post about horror stories saying don't heat it, then I have seen Kevin Cashen say he heats it to 130F)
3) Temp that 1095 becomes non-magnetic? (No good info found, one post said 1560F but that sounds a little high and weird)


It took a couple of hours of searching to find the different info and I may have missed something. The only other thing that would relate to Hamons and the HTing would be, I have noticed that some people say do not go back to the grinder after HTing? I don't use gloves so my steel stays pretty cool because I can feel it heating up so is that still ok when trying to get hamons?
 
Last edited:
What makes Aldo's 1095 better than others is that it was formulated with a higher manganese level than most have. You could use Parks #50 but when I saw others use it at a hammer-in two years ago they were using an oil, probably a vegetable oil. You could also try water or brine with a little detergent in it. Call Aldo now that the Atlanta show is over and ask him. Yes, it can be a little temperamental to work with. It will need a soak for about 5 minutes at 1475-1500 degrees so as not to exceed the upper critical temperature in cause grain growth. If you use Parks #50 use it at room temperature. I know that Kevin has a good reason for 130 degrees, if that's what he uses, but that's above spec's for that quenchant. Steels pretty much become non-magnetic at the same temperature around 1430-1440 if I remember correctly. It sure seems that way from the IT diagrams that I have.

You can use a grinder to do the finish grind after heat treating. Grind a little and cool in water often. The only time that I etched for a quench line I sanded on the grinder out to approximately 600 grit and then switched to wet/dry sand paper, lubricating with WD-40 out to 1800 grit and then etched in ferric chloride.
IMG_0137.jpg
Above is what I got with this process after differential hardening with a clay coat, similar to making a hamon, with 9260 on a test knife.

Doug
 
Here is how I treat 1095. 1. Heat the blade to 1200-1225 and air cool to black for a stress relief. 2 Heat it to 1475 and soak for 6-8 minutes then quench in Parks #50. Temper twice for 2 hours each time. The temp. that steel goes non-magnetic is 1414 and is called the Curie point. It is the same for all steels. I think what is meant is don't go back to the grinder until you temper the blade. It is necessary to grind the blade after H/T to remove the scale. As long as you don't exceed the tempering temp you will be fine. I grind with bare hands after H/T to insure that I don't get the blade too hot. If you can hold it with bare hands its not hot enough to hurt anything. Hope this helps.

Doug gave you good info.. I type too slow.
 
Last edited:
The only place that I would differ from what Darrin does is that I would still take the 1095 up to non-magnetic and air cool for three cycles, normalization. Darrin's method will relieve stress but it won't cycle the iron crystals in the steel through the phase changes to decrease grain size. I forge blades so that step is very important to me. On Kevin Cashen's advice, do not anneal 1095. The slow cool down will cause the from austinizing temperatures will cause the carbides to clump because the steel is kept hot too long.

One thing that I meant to mention from your first post. You said that you questioned the temperature of 1560 degrees to reach non-magnetic. One thing to be careful of is when refer to temperatures that they get with their equipment. Especially if that is the temperature of the forge that is being used, that may the temperature of the pyrometer in the forge not the temperature of the steel in the forge. I know that it seems contradictory but difference in the placement of the two will effect things. BTW, thanks, Darrin, for looking up the temperature of the Curie point. Didn't feel like digging into my texts last night and just went by what I saw on the IT diagrams.

Another thing that you can look for is (I know I'm spelling this wrong but it's not in the dictonary) decalessance. It's like a shadow that passes over the steel as it heats, the same thing also happens as the steel cools from above austinizing temperatures. As you heat the steel it will start to get brighter then you will notice that the steel will dull, like a shadow is cast over it. This will not be even across the blade as the thickness of the steel will influence this. The easiest way that I learned to see it is to get the steel above austinizing temperatures and then watch for the shadow, dim lighting will help, as the steel cools. Once that you're sure that you see it then look for the same thing as you heat the steel. Reduced lighting always helps, some go so far as only heat treating at night by the light provided by their forges, but once you know what you're looking for being out of direct light will be all that you need. I still check with a magnet as a backup.

Doug
 
Back
Top