Heat treatment??
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Billycan,
You really don't need that much to do the heat treatment yourself.
I do it the following way:-
In a bucket of ash from our kitchen range (granted you might not have a range, but any pile of ash that you can gather into a hollow will do). Make a depression big enough to take the blade that you want to treat, the ash reflects the heat from the blow torch. This is my "forge".
I heat with a normal gas blow lamp, just play the flame right onto the piece of steel.
Using a magnetic pick-up tool, once the steel is glowing red, check to see when they stop being attracted. This is when the carbon is changing within the steel and ready to be quenched.
Quickly plunge the blade into a vessel of vegetable oil, edge first and hold it so that it does not touch the sides of the vessel. The blade should now be as hard as it will ever get, (if you try filing it, the file should skate over the surface) but it will be brittle.
Next step is to temper the steel, sacrificing a bit of the hardness for toughness.
Clean the blade down to bare steel so that you can see changes of colour. You can gently bake the blade in the oven at about 170 deg - ish till it just starts to turn a straw colour and slowly let it cool to room temperature.
There are some who like to do the quenching operation three times (tripple quenching) to get slightly better results - but I recon for the sake of doing your own, it'll be plenty good enough.
The hard part for me was stopping at just one blade - I didn't manage that at all.
Try it, its addictive
Ogri the trog
You really don't need that much to do the heat treatment yourself.
I do it the following way:-
In a bucket of ash from our kitchen range (granted you might not have a range, but any pile of ash that you can gather into a hollow will do). Make a depression big enough to take the blade that you want to treat, the ash reflects the heat from the blow torch. This is my "forge".
I heat with a normal gas blow lamp, just play the flame right onto the piece of steel.
Using a magnetic pick-up tool, once the steel is glowing red, check to see when they stop being attracted. This is when the carbon is changing within the steel and ready to be quenched.
Quickly plunge the blade into a vessel of vegetable oil, edge first and hold it so that it does not touch the sides of the vessel. The blade should now be as hard as it will ever get, (if you try filing it, the file should skate over the surface) but it will be brittle.
Next step is to temper the steel, sacrificing a bit of the hardness for toughness.
Clean the blade down to bare steel so that you can see changes of colour. You can gently bake the blade in the oven at about 170 deg - ish till it just starts to turn a straw colour and slowly let it cool to room temperature.
There are some who like to do the quenching operation three times (tripple quenching) to get slightly better results - but I recon for the sake of doing your own, it'll be plenty good enough.
The hard part for me was stopping at just one blade - I didn't manage that at all.
Try it, its addictive
Ogri the trog
how bout a one brick or two brick forge.....
http://www.britishblades.com/forums/showthread.php?t=10800
http://www.britishblades.com/forums/showthread.php?t=11056
even easier is a coffee can forge..... just line it will ceramic wool...
hopefully someone close by will offer to heat treat it..... it should be no problem
take care
Greg
http://www.britishblades.com/forums/showthread.php?t=10800
http://www.britishblades.com/forums/showthread.php?t=11056
even easier is a coffee can forge..... just line it will ceramic wool...
hopefully someone close by will offer to heat treat it..... it should be no problem
take care
Greg
First off i have never heat treated a blade. I don't expect to either since my brother could sort if for me in their testing HT oven.
I've always been told that O1 is a easy one to HT compared to others and from use haven't noticed any really bad performers which I think means that the makers got it more or less right.
If you really don't want to HT yourself Shing will for a small fee plus return postage
I've always been told that O1 is a easy one to HT compared to others and from use haven't noticed any really bad performers which I think means that the makers got it more or less right.
If you really don't want to HT yourself Shing will for a small fee plus return postage
If you don't plan on making more knives I would go over to British Blades and find someone who will heat treat your blades for you. If you don't have the torch and magnet and insulation materials already it will cost you more to get them than it will to pay someone to do your blade three times over. However, there is no free lunch, just because someone has made a lot of knives, or is a proffesional, it does not meen that they will100% do the heat treat right. There is just a higher probablity that they will do better than you on your first try or 5. 
My first handles turned out pretty good. My first heat treat did not.
With regard to quenching as soon as O-1 has reached non-magnetic, that isn't always the best route. If you are using a simple plumbers torch (say Go-Gas or Bernzomatic from B&Q) the chances are that you aren't going to get the blade hot enough, long enough, to burn the carbon, or start grain growth. What you will do by heating longer is get more carbon into solution and get closer to the full hardness for the steel. I recently did some tests with a propane/butane torch and single hollow firebrick, the steel that was heated once and qunched was pretty poor, tempering brought it to about 55Rc, some was lower still Best results were from cycling temperatures and keeping the steel above non-magnetic for 4-5minutes at a time. The rules about instant quenching are more important on simple carbon steels as found in springs and bearings. O-1 really does better with a longer heating.
My first handles turned out pretty good. My first heat treat did not.
With regard to quenching as soon as O-1 has reached non-magnetic, that isn't always the best route. If you are using a simple plumbers torch (say Go-Gas or Bernzomatic from B&Q) the chances are that you aren't going to get the blade hot enough, long enough, to burn the carbon, or start grain growth. What you will do by heating longer is get more carbon into solution and get closer to the full hardness for the steel. I recently did some tests with a propane/butane torch and single hollow firebrick, the steel that was heated once and qunched was pretty poor, tempering brought it to about 55Rc, some was lower still
Best results were from cycling temperatures and keeping the steel above non-magnetic for 4-5minutes at a time. The rules about instant quenching are more important on simple carbon steels as found in springs and bearings. O-1 really does better with a longer heating.Heres some useful info about O1 and its heat treatment.
http://www.crucibleservice.com/eselector/prodbyapp/tooldie/ketos.html
I temper at 260C to give a slightly softer blade to make it easier to sharpen and a little tougher too.
http://www.crucibleservice.com/eselector/prodbyapp/tooldie/ketos.html
I temper at 260C to give a slightly softer blade to make it easier to sharpen and a little tougher too.
billycan said:
Try here :http://www.cromwell.co.uk/category?code=160202
Give the heat treatment a go. I heat treat my blades in a simple 2 brick kiln ("face" bricks - look up refractory supplies/engineers in yellow pages) and a mapp torch from B&Q. The results are not perfect Im sure but it does the job for me and the satisfaction you get knowing that you made the blade/knife yourself from start to finish is as far as Im concerned well worth it.
http://i30.photobucket.com/albums/c332/neiltoo/Firstknife011.jpg
http://i30.photobucket.com/albums/c332/neiltoo/Firstknife013.jpg
try to drill your pin holes before heat treating... as o1 sometimes airhardens a little bit and it could give you trouble later...
i've done a couple of o1 knives in my small coffee can forge... .... you have to make sure that you heat the spine first.... then even out the heat to the blade edge....
- make sure that both sides of the blade are evenly heated.....if one side is hotter than the other....it will definitely warp in the quench...
hold the heat near non-mag for 6 to 10 min... and quench it in a warm veg oil....
O1 is a very good steel for knives.... it will hold a very good edge...
one of the nice things about heating in a one brick or coffee can forge is that you don't have too much heat...... it is easy to over heat the steel and cause grain growth..
check out the tutorial on Tai's site..... there another way of doing it... look at the tutorial section....and click on the pic's
http://www.taigoo.com/tutorial/frameset.html
making a charcoal forge is very simple... and the pine heat treat works real good..
take care
Greg
i've done a couple of o1 knives in my small coffee can forge... .... you have to make sure that you heat the spine first.... then even out the heat to the blade edge....
- make sure that both sides of the blade are evenly heated.....if one side is hotter than the other....it will definitely warp in the quench...
hold the heat near non-mag for 6 to 10 min... and quench it in a warm veg oil....
O1 is a very good steel for knives.... it will hold a very good edge...
one of the nice things about heating in a one brick or coffee can forge is that you don't have too much heat...... it is easy to over heat the steel and cause grain growth..
check out the tutorial on Tai's site..... there another way of doing it... look at the tutorial section....and click on the pic's
http://www.taigoo.com/tutorial/frameset.html
making a charcoal forge is very simple... and the pine heat treat works real good..
take care
Greg
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