Okay im working on a small knife.I have forge out the basic shape of the blade today and filed down the blade smooth.
Now i am starting to think about the finish on the knife, and would like to have a hamon ( temper line ) on the blade.
Now I know how it is don but what i would like to know could i use fire cement to put on the spine of the blade when Harding it.

Here is a small picture of the knife.



Any help would be of gait help to me.
Thank's.

First: Is it made from an alloy that produces hamons? Most don't.

Then: I know you can use furnace cement; I'm not sure what fire cement in Ireland translates to over here.
Most likely yes if you can get it to stick to the blade.

Okay im working on a small knife.I have forge out the basic shape of the blade today and filed down the blade smooth.
Now i am starting to think about the finish on the knife, and would like to have a hamon ( temper line ) on the blade.
Now I know how it is don but what i would like to know could i use fire cement to put on the spine of the blade when Harding it.

Here is a small picture of the knife.



Any help would be of gait help to me.
Thank's.

Like was said it needs to be a shallow hardening steel such as w1,w2 or 10xx.
Yes i use normal furnace cement to coat my blades and it does what i want it to.
Also it need to be a fast quenching oil or water if you choose water be prepared for some broken and cracked blades.

Good luck Bob

First: Is it made from an alloy that produces hamons? Most don't.

Then: I know you can use furnace cement; I'm not sure what fire cement in Ireland translates to over here.
Most likely yes if you can get it to stick to the blade.

The steel is 5160 as far as i know it is an alloy steel ( I use the search bar to find out that answer )
It's cut from a leaf spring a very thick one 10mm thick.

That's not a small pic if you click on it. Anyway, lookin' good.

Like was said it needs to be a shallow hardening steel such as w1,w2 or 10xx.
Yes i use normal furnace cement to coat my blades and it does what i want it to.
Also it need to be a fast quenching oil or water if you choose water be prepared for some broken and cracked blades.

Good luck Bob

I have old engine oil, the steel is 5160.

Thank's

For the heat treats I've done, I use old frying oil. it seems to work ok, though it does leave some undesirable crud on the blade.

Just found out that 5160 steel will not give me the temper line (hamon ) that i would like. so ill have to do with out
Search bar help me out again with this answer

Any way do i use oil for Harding ?

Thanks for the help so far :)

I've heard that using things other than oil can cause the blade to crack or even shatter when immersed. I'll wait for someone to back me up on that, but I'm pretty sure.

Yes use oil canola oil will work heat the oil up first then quench your blade.

Bob

If you don't know what to use; oil is a good first guess. If it's not hard enough (under any decarb layer), re-do it in brine. If it shattered in oil; well it was an air hardening alloy---not very common in the scrap stream though.

What exactly is the composition of brine? I know its salt and water, but what's the ratio?

Traditionally you added salt to your water till it would float an egg. I assume this would be a *fresh* egg in those days and not a dried out in processing and storage egg.

ok, well fresh water is 8.34 ppg, saturated brine is right at 14 ppg.sea water is 9.4 ppg on the avarage. but most brine quenches is in the 1:1 catagory...1 gal. water to 1 # salt.but i think anything between 9.5 to 10 ppg will work sufficently.hope this totaly confuses you, good luck, jimmy.

Okay guy's iv just don the heat treat ( Hardening ) of my knife. I used old engine oil, and as far as i can see no sing of crack's the tang is soft but the blade is hard.
Now Tempering of the blade, What's the easy-es way of doing it or the best way of doing it.

lol i stink of burnt engine oil

Here is a picture of the knife.

Stick it in your oven for a few hours at at least 350 degrees Fahrenheit, or maybe 150 Celsius. You need to do it quickly after hardening, I've heard stories of blades randomly shattering from internal stress because the smith waited too long to temper them. Ask someone else for the exact temperatures though, I've only done this once.

Stick it in your oven for a few hours at at least 350 degrees Fahrenheit, or maybe 150 Celsius. You need to do it quickly after hardening, I've heard stories of blades randomly shattering from internal stress because the smith waited too long to temper them. Ask someone else for the exact temperatures though, I've only done this once.

Thank you for telling me that Iv put it in the oven to at 350d* F.

Oh do i leave it to cool down in the oven after it's bin in for a few hours, when i tern the oven off ?

Dean
I would temper at 400f for two hours should be around rc60 then let it cool in the oven to room temp. It never hurts to do it twice.

Bob

Dean
I would temper at 400f for two hours should be around rc60 then let it cool in the oven to room temp. It never hurts to do it twice.

Bob

Cool thanks for the info

Sorry but what dose rc60 mean i tried the search bar but could not fined an answer.

Rc is rockwell hardness is a scale to measure the hardness of your blade.

Bob

How do you test Rc? I've never heard of it.

rockwell hardness is tested by a machine that pretty much hits the metal mith a small center punch and measures the hardness of the metal from what i have heard. correct me if im wrong

rockwell hardness is tested by a machine that pretty much hits the metal mith a small center punch and measures the hardness of the metal from what i have heard. correct me if im wrong

You are right on Adam.

Bob

the reason i know about one my uncle brought up the fact wondering just how hard one of my knives was and he told me they had a rc tester at the plant he works at

Hi all i finished that knife i was making so here are some pic's for you.





and here is a link to a video iv got on youtube.

My video