Excellent video, glen. The time a piece needs in the forge is still one of the most difficult decisions for me. Too bad people have to complain about your bubble forge, it's not really that big of a deal. But, people have to complain about something. Very enjoyable and informative. Thanks for sharing what you know.
Christopher, While you want make sure your workpiece is just beyond critical temperature when heat treating (hardening, normalizing or annealing), you don't want to go too far beyond this (in most cases). We mostly just temperature by color but this can be tricky depending on the forge type, the lighting, etc. Pull your workpiece out periodically and touch it to a magnet. If the magnet sticks, heat it more, it not, you're at critical temperature. The negativity doesn't bother me at all anymore - I'll just continue to do my thing. Thanks for sure. Glen
Nice rundown on heat treatment. Only small nitpick I have is that the medium temperature affects the quench rate in the opposite way as was stated in this video. Preheated oil or water cools the metal faster than cold medium, seemingly paradoxically. The heat is pumped out by vaporization of the medium. Water vaporizes at 100 celsius and is a fast quench. Oil vaporizes around 300 celsius, a slower quench. Therefore the easier to vaporize the medium, the faster the quench.
I can understand the theory /science of what you're saying about a warmer (preheated) medium cooling faster but in practice it really doesn't seem this way. Could it also have something to do with the amount of water or oil being used? Very curious... Thanks for your input and have a great holiday season.
Thanks, for the reply, glen. Happy holidays to you! I use almost exclusively oil quenches, since I now have a nice, safe setup for it. When I make a set of punches/chisels/drifts, a half dozen at once or something, the oil starts off cold and gets up way hotter than boiling water when I'm done. Full emersion dunks, left to chill in the oil for 30 seconds or so. The last few quenches sound a lot more "snappy" than the first few, and the tools tend to harden further up the shaft. Not sure if they are actually harder at the tip, though. My experience/gut tells me that each point in the steel "either hardened or didn't" and there isn't that much variability. The presence and degree of propagation of fractures is what changes, at some point. Like water quenching a file doesnt actually make a "super diamond file", it makes a normal file that is loaded with stresses and (most likely) micro-fractures. The real, old-school, blacksmith shops that I've visited around here (Canada) all mainly use the "differential" water quench method (dunk the tip only) that you seem to favour, to great success. It feels "wrong" to me, since it ends up yoyo-ing the steel temperature, if the dunk depth isn't perfectly constant, which could cause lots of flexes, warps and stresses at the transition. Anyways, you've inspired a christmas day experiment: I'll quench identical pieces of 1018 and 1045 in ice water v.s. boiling and the beat them up in the vice. Edit: Oil is noticeably more runny, and it "wets" up the sides of the tank when hot. I guess you could theoretically get some oils hot enough to temper the steel as well... Cheers!
Id assume you quenched twice because maybe where you are the resting temp for ya water is warmer than other places? I watched a video where a guy used a hose so it didnt have a chance to heat up the water as it's constantly refreshed, maybe this is worth a try?
Hi Glen, great video on the heat treating. Also watched some of your videos on hammer making and got to tell you like the fact you make them all your style. You mentioned that one should not go much beyond the non magnetic temperature. Why is that a bad idea. I found that I had more success with a high carbon steel when I quenched in water at orange, but I am new to this. If you could let me know would be great.
In my opinion, when you take a heat much beyond critical temperature heavy scale can begin to form (though this is not always the case depending on your forge and how it is running). Scale can prevent the workplace from cooling properly and steam can get trapped between the scale and workpiece and explode, causing cracks. But if you are having success with your method, then I can't argue with that. There are many factors involved but typically you don't want to go far beyond critical temperature before quenching. Thanks for watching. Glen
Heath, I can't say for sure that the angle is a factor but I know I've had better success when quenching at an angle. Anyway, it's something to ponder. Thanks for watching. Glen
As a unexperienced beginner with no knowledge in blacksmithing i realy like this. I have been quenching and testing things out myself, trial and error type thing :P So thanks for the knowledge!
Trial and error is actually the best way to learn in my opinion. But it helps to have a foundation to build upon plus ruining projects by improperly heat treating can be frustrating. But we've all been there... Thanks for watching. Glen
I have started forging recently to make my own arrowheads. Is it okay to just heat them up and throw them in water? I have seen some people also using oil, but i am not sure which kind of oil they use
I saw this double (maybe sometimes triple) hardening technique on another video some time back. It definitely works for the steels I normally heat treat, 1045 and 1050. In this blacksmithing community, we're all learning from each other... Thanks.
hi glen does your friend with the mystery quench pre heat the oil first i imagine the oil temp would be a factor as you mentioned, detergent based oils ie omd types (oil mineral detergents) used in diesel engines would be less likely to flare?
As far as I know, he doesn't preheat his oil. I heard him say it's a blend of 3 or 4 different kinds of oils and honestly, it smells somewhat like cooking oil. He heat treats the touch marks made by the engraver which are H13. I told him that when I was in the States, I used to use old motor oil to oil quench and he told me that was not a good idea. Thanks.
Honestly, I'm not very good at making blades. I sometimes have a go at it and I'm sure I'll post another knife video or two but making knives just isn't a great interest of mine. Thanks. Glen
Glad you found this interesting. I will touch on this subject again - talk more about annealing, and normalizing, in addition to just hardening... Thanks.
Nice video i use to do the same thing but the second time i heated it just a shade or two less than the first time and just put the piece in the water and moved it around and not taking it in and out of the water and it worked very well but many critisized that its not the right way so now i do it like everyone else i was surprised to see someone doing almost the same thing ,very nice video god bless.
Hi and thanks for your comment. I understand what you mean about being criticized for not heat treating traditionally. But if it works for you (and me), that's all that matters. Good luck in you work.
@@gstongs i watched your video carefully you explain all the steps carefully and in detail with a kind of sincerity ,thanks for sharing your experience that im sure has taken you many years to master and puting it out there for everyone to benifit from .
Very interesting Glen. I would never have imagined a double hardening. How can this be so? How does the martensite not go back into an austenite solution on the 2nd heat cycle? Nonetheless I believe what you have said. You have much experience at this. I have double-tempered pieces but never double-hardened.
I think in order for it to go back to austenite it needs to be cooled very slowly and not just reheated. But I understand what you mean - it seems like the structure of the molecules should change once reheated to critical temperature thus eliminating the hardness (or maybe just some) from the first quench. I can't fully explain why this works but it does. Give it a go and see what happens... Thanks.
You must have read my mind I was going to send you an email on this very subject. Would this quenching method work for something like a hot cut hardy tool? I have access to 1050 which is about what you are working with there. Would the Hardy tool need to be tempered or just run it through this type of cycle?
Neil, In my experience, 1050 does not normally need to be tempered if hardening in this way. But this really depends on the workpiece and how quickly it is cooled. With a hardy tool that has an edge (like a hot cut), you might want to temper back the edge just slightly. Also, in this video, I used 1045 and did the double hardening. But I have found that the extra carbon in 1050 may make it less necessary to do this double hardening technique. Try the file test after the first hardening an make a determination from there. To sum up, I personally feel you won't need to temper medium carbon steel, even an edge tool, if it is to be used for working hot steel. For example, if you have a hardened 1050 hardy hot cut, the first time you touch hot steel to the edge, it will loose some hardness. But having the tool hardened deeply with this double technique keeps it from losing too much hardness and deforming too easily. I hope the helps. Thanks.
Tony, I never tried it and didn't even know it was possible. It sounds like and old school quenching medium and I'm guessing it's probably diluted quite a bit. I'm not sure what, if anything, it does. I will research this a bit. Sorry I couldn't help but thanks for introducing this to me.
I was refering to the light grey marble-like colour on the surface of the steel. First sign of a good quench. Thanks for your videos, they're always fun to watch.
Hi Glen. Thanks for your awesome videos and sharing your knowledge and experience. Do you preheat the water? Or, what approximate temperature do you like it to be?
That's a good question. Yes, I typically preheat my water and do so by making some other things first, like tongs, that I frequently quench when working. I can't say the exact temperature but I would say warm like bath water which is easy to accomplish in my small slack bucket. Thanks.
I can't rid myself of the dreaded bubbling background noise completely. I'll get a new camera eventually but in the meantime I'll have to be the underwater blacksmith... Anyway, thanks for watching.
salt in high concentrations is used for file making and higher carbon steels...also different salts are used for different tempratures....often dipped until glazed first like a flux to test for accurat temp then quenched. dirty motor oil is mostly only for case hardening....as for annealing....most blanks come pre annealed...that may be why you have no issues but if you scrounge steel....anneal....or at least normalise.
SECRET OIL ' is the recipe making the man rich? I don't understand why a person wouldn't tell the world about something to make life easier. If you take something to the grave it's probably a lonely place.
George, Ring the bell, school is in session! I learned this double hardening technique from someone else so the schooler was also the schoolee - we all learn form each other... Thanks.
Excellent video, glen. The time a piece needs in the forge is still one of the most difficult decisions for me. Too bad people have to complain about your bubble forge, it's not really that big of a deal. But, people have to complain about something. Very enjoyable and informative. Thanks for sharing what you know.
Christopher, While you want make sure your workpiece is just beyond critical temperature when heat treating (hardening, normalizing or annealing), you don't want to go too far beyond this (in most cases). We mostly just temperature by color but this can be tricky depending on the forge type, the lighting, etc. Pull your workpiece out periodically and touch it to a magnet. If the magnet sticks, heat it more, it not, you're at critical temperature. The negativity doesn't bother me at all anymore - I'll just continue to do my thing. Thanks for sure. Glen
Nice rundown on heat treatment. Only small nitpick I have is that the medium temperature affects the quench rate in the opposite way as was stated in this video.
Preheated oil or water cools the metal faster than cold medium, seemingly paradoxically.
The heat is pumped out by vaporization of the medium.
Water vaporizes at 100 celsius and is a fast quench. Oil vaporizes around 300 celsius, a slower quench. Therefore the easier to vaporize the medium, the faster the quench.
I can understand the theory /science of what you're saying about a warmer (preheated) medium cooling faster but in practice it really doesn't seem this way. Could it also have something to do with the amount of water or oil being used? Very curious... Thanks for your input and have a great holiday season.
Thanks, for the reply, glen. Happy holidays to you!
I use almost exclusively oil quenches, since I now have a nice, safe setup for it. When I make a set of punches/chisels/drifts, a half dozen at once or something, the oil starts off cold and gets up way hotter than boiling water when I'm done. Full emersion dunks, left to chill in the oil for 30 seconds or so.
The last few quenches sound a lot more "snappy" than the first few, and the tools tend to harden further up the shaft. Not sure if they are actually harder at the tip, though. My experience/gut tells me that each point in the steel "either hardened or didn't" and there isn't that much variability. The presence and degree of propagation of fractures is what changes, at some point. Like water quenching a file doesnt actually make a "super diamond file", it makes a normal file that is loaded with stresses and (most likely) micro-fractures.
The real, old-school, blacksmith shops that I've visited around here (Canada) all mainly use the "differential" water quench method (dunk the tip only) that you seem to favour, to great success. It feels "wrong" to me, since it ends up yoyo-ing the steel temperature, if the dunk depth isn't perfectly constant, which could cause lots of flexes, warps and stresses at the transition.
Anyways, you've inspired a christmas day experiment: I'll quench identical pieces of 1018 and 1045 in ice water v.s. boiling and the beat them up in the vice.
Edit:
Oil is noticeably more runny, and it "wets" up the sides of the tank when hot.
I guess you could theoretically get some oils hot enough to temper the steel as well...
Cheers!
Your knowledge is much appreciated.
Thumbs up, nice demonstration of hammer hardening.
Thanks Glen, another snippet of info to put into my brain!
Id assume you quenched twice because maybe where you are the resting temp for ya water is warmer than other places?
I watched a video where a guy used a hose so it didnt have a chance to heat up the water as it's constantly refreshed, maybe this is worth a try?
Hi Glen,
great video on the heat treating. Also watched some of your videos on hammer making and got to tell you like the fact you make them all your style. You mentioned that one should not go much beyond the non magnetic temperature. Why is that a bad idea. I found that I had more success with a high carbon steel when I quenched in water at orange, but I am new to this. If you could let me know would be great.
In my opinion, when you take a heat much beyond critical temperature heavy scale can begin to form (though this is not always the case depending on your forge and how it is running). Scale can prevent the workplace from cooling properly and steam can get trapped between the scale and workpiece and explode, causing cracks. But if you are having success with your method, then I can't argue with that. There are many factors involved but typically you don't want to go far beyond critical temperature before quenching. Thanks for watching. Glen
Cool thanks will keep an eye on it. Your video was very good so the thanks should be on my part :)
David.
Great video. I have never thought of the angle of insertion to be a factor. Thank you
Heath, I can't say for sure that the angle is a factor but I know I've had better success when quenching at an angle. Anyway, it's something to ponder. Thanks for watching. Glen
Love your videos! I'm gonna try your heat treating method. I'm always open to new ideas. :)
Give this method a try. I think you'll find this double hardening does work. Thanks for watching. Glen
As a unexperienced beginner with no knowledge in blacksmithing i realy like this. I have been quenching and testing things out myself, trial and error type thing :P So thanks for the knowledge!
Trial and error is actually the best way to learn in my opinion. But it helps to have a foundation to build upon plus ruining projects by improperly heat treating can be frustrating. But we've all been there... Thanks for watching. Glen
I have started forging recently to make my own arrowheads. Is it okay to just heat them up and throw them in water? I have seen some people also using oil, but i am not sure which kind of oil they use
Nice technique Glen. I’ll have to give it a try
I saw this double (maybe sometimes triple) hardening technique on another video some time back. It definitely works for the steels I normally heat treat, 1045 and 1050. In this blacksmithing community, we're all learning from each other... Thanks.
When you enter the metal in angle you will create a loop on the metal with the warmer water longer and fairly mixing in circles 🌪
hi glen
does your friend with the mystery quench pre heat the oil first i imagine the oil temp would be a factor as you mentioned, detergent based oils ie omd types (oil mineral detergents) used in diesel engines would be less likely to flare?
Really learned a lot. Will you forge blade one day?
As far as I know, he doesn't preheat his oil. I heard him say it's a blend of 3 or 4 different kinds of oils and honestly, it smells somewhat like cooking oil. He heat treats the touch marks made by the engraver which are H13. I told him that when I was in the States, I used to use old motor oil to oil quench and he told me that was not a good idea. Thanks.
Honestly, I'm not very good at making blades. I sometimes have a go at it and I'm sure I'll post another knife video or two but making knives just isn't a great interest of mine. Thanks. Glen
Great info Glen, Thank you..
Glad you found this interesting. I will touch on this subject again - talk more about annealing, and normalizing, in addition to just hardening... Thanks.
Nice video i use to do the same thing but the second time i heated it just a shade or two less than the first time and just put the piece in the water and moved it around and not taking it in and out of the water and it worked very well but many critisized that its not the right way so now i do it like everyone else i was surprised to see someone doing almost the same thing ,very nice video god bless.
Hi and thanks for your comment. I understand what you mean about being criticized for not heat treating traditionally. But if it works for you (and me), that's all that matters. Good luck in you work.
@@gstongs i watched your video carefully you explain all the steps carefully and in detail with a kind of sincerity ,thanks for sharing your experience that im sure has taken you many years to master and puting it out there for everyone to benifit from .
Very interesting Glen. I would never have imagined a double hardening. How can this be so? How does the martensite not go back into an austenite solution on the 2nd heat cycle?
Nonetheless I believe what you have said. You have much experience at this.
I have double-tempered pieces but never double-hardened.
I think in order for it to go back to austenite it needs to be cooled very slowly and not just reheated. But I understand what you mean - it seems like the structure of the molecules should change once reheated to critical temperature thus eliminating the hardness (or maybe just some) from the first quench. I can't fully explain why this works but it does. Give it a go and see what happens... Thanks.
Thanks for the reply Glen. I aim to give it a try yes.
Thank you Glen
Doug, My pleasure. Thanks for sure.
You must have read my mind I was going to send you an email on this very subject. Would this quenching method work for something like a hot cut hardy tool? I have access to 1050 which is about what you are working with there. Would the Hardy tool need to be tempered or just run it through this type of cycle?
Neil, In my experience, 1050 does not normally need to be tempered if hardening in this way. But this really depends on the workpiece and how quickly it is cooled. With a hardy tool that has an edge (like a hot cut), you might want to temper back the edge just slightly. Also, in this video, I used 1045 and did the double hardening. But I have found that the extra carbon in 1050 may make it less necessary to do this double hardening technique. Try the file test after the first hardening an make a determination from there. To sum up, I personally feel you won't need to temper medium carbon steel, even an edge tool, if it is to be used for working hot steel. For example, if you have a hardened 1050 hardy hot cut, the first time you touch hot steel to the edge, it will loose some hardness. But having the tool hardened deeply with this double technique keeps it from losing too much hardness and deforming too easily. I hope the helps. Thanks.
Thanks for the details.
I use lye for hardening steel, would you recommend this ?
Tony, I never tried it and didn't even know it was possible. It sounds like and old school quenching medium and I'm guessing it's probably diluted quite a bit. I'm not sure what, if anything, it does. I will research this a bit. Sorry I couldn't help but thanks for introducing this to me.
Also the colour of the hammer head showed martensite after the second quench
Philip, I never knew that hardened steel (martensite) has a color. Is this somewhat like the temper colors? Thanks for watching and sharing. Glen
I was refering to the light grey marble-like colour on the surface of the steel. First sign of a good quench. Thanks for your videos, they're always fun to watch.
Great video like always my friend thank you and God bless✝
Rick, Thanks for continuing to watch and for your well wishes. Take care. Glen
Nice job Glen
Thanks Dave. Take care.
Hi Glen. Thanks for your awesome videos and sharing your knowledge and experience. Do you preheat the water? Or, what approximate temperature do you like it to be?
That's a good question. Yes, I typically preheat my water and do so by making some other things first, like tongs, that I frequently quench when working. I can't say the exact temperature but I would say warm like bath water which is easy to accomplish in my small slack bucket. Thanks.
Very nice video!!
I appreciate your comment. Thanks. Glen
Encore une fois merci pour cette vidéo qui est très instructive !!!!!!
P.S: j'aime beaucoup Taiwan, j'aimerais vraiment y aller un jour.
Adem, I hope you get a chance to visit Taiwan one day - let me know and we'll get a beer... Glad you like this video. Thanks.
Good stuff submarine man.
I can't rid myself of the dreaded bubbling background noise completely. I'll get a new camera eventually but in the meantime I'll have to be the underwater blacksmith... Anyway, thanks for watching.
I'm just teasing you, we don't really hear the bubbling sound anymore, at least not like it used to be. ;)
Insert with angle let water make a blanket Bubbles that prevents fast cooling
salt in high concentrations is used for file making and higher carbon steels...also different salts are used for different tempratures....often dipped until glazed first like a flux to test for accurat temp then quenched.
dirty motor oil is mostly only for case hardening....as for annealing....most blanks come pre annealed...that may be why you have no issues but if you scrounge steel....anneal....or at least normalise.
Scott, I appreciate your insightful comments about salt and its use in quenching, etc. Thanks. Glen
SECRET OIL ' is the recipe making the man rich? I don't understand why a person wouldn't tell the world about something to make life easier. If you take something to the grave it's probably a lonely place.
you way way way to hot when you quench. It's best to move in a fairly rapid pace in a figure 8 pattern
schooled
George, Ring the bell, school is in session! I learned this double hardening technique from someone else so the schooler was also the schoolee - we all learn form each other... Thanks.