temper question

V

victoroni

Well-Known Member
don't know if this has been previously covered- couldn't find a definitive answer - question, when a tempering "recipe" calls for lets say, two one hour cycles , am i to assume that includes a cooling period between cycles ?
 
Yes. I do 2, 2 hour cycles for most everything though. Do one cycle, let cool to room temp, check for straightness. Clamp to angle for straightening, do second cycle, let cool to room temp then unclamp.
 
Some say quench it after you pull it out of the temper oven. IIRC, Roman Landes being one of those "some." ;)
 
Last edited:
victoroni said:
am i to assume that includes a cooling period between cycles
Click to expand...
Yes. After the first 2 hours, remove the blade, then cool the blade in air until it reaches room temperature - which typically only takes a few minutes - then reinsert into tempering oven that is set to your target temperature.
 
I've been tempering @ 450 for 2 hours and having good luck doing it. Is there any benefit of doing 2, 1 hour cycles?
 
Tooln said:
I've been tempering @ 450 for 2 hours and having good luck doing it. Is there any benefit of doing 2, 1 hour cycles?
Click to expand...

I have better hardness with the two two-hour cycles.

Are you tempering everything at 450 or just a certain steel?
 
Just curious, could anybody expand, in detail, why they follow a specific tempering regimen? Not what they heard somebody else say*, but what is the underlying reasoning is behind the prescribed method? I only ask because tempering has become a topic that is often a source of head scratching puzzlement for me when I visit the internet anymore, and I am just trying to understand.

* Not singling anybody out here, Landes is a good source, I have spent many hours, with lots of adult beverages and even walking local rivers with fishing poles (and even more beverages) with Roman while discussing every topic imaginable. So this question even applies to those who may say "Cashen said..."
 
Kevin R. Cashen said:
Just curious, could anybody expand, in detail, why they follow a specific tempering regimen? Not what they heard somebody else say*, but what is the underlying reasoning is behind the prescribed method? I only ask because tempering has become a topic that is often a source of head scratching puzzlement for me when I visit the internet anymore, and I am just trying to understand.

* Not singling anybody out here, Landes is a good source, I have spent many hours, with lots of adult beverages and even walking local rivers with fishing poles (and even more beverages) with Roman while discussing every topic imaginable. So this question even applies to those who may say "Cashen said..."
Click to expand...

I'm too new to this to have a solid answer. I've experimented a bit and the two two-hour cycles seems to give me a bit more hardness. I read as much as I can find and then try a mix until I find what works for me.

May I ask what your tempering regime is? I know you are a well respected maker and maybe you can shed some light for me.
 
CDHumiston said:
I'm too new to this to have a solid answer. I've experimented a bit and the two two-hour cycles seems to give me a bit more hardness. I read as much as I can find and then try a mix until I find what works for me.

May I ask what your tempering regime is? I know you are a well respected maker and maybe you can shed some light for me.
Click to expand...
To be honest I have some soul searching occurring here. After 30+ years of observing what makes a well respected maker I am not sure what puts me there. As a habit, our craftsman community seems to be bound to a one step forward, two steps back, approach that no amount of effort, or time, will ever overcome due to the value we put on the mere words of those who we perceive as being anywhere from 1 week to 30 years ahead of us, or their proficiency in a given social media or other self promotional effort.

I honestly am not trying to stir any %#@ here. For my input on this, a quick Google search, or just a search of this forum alone, could give you what you ask for. But after a literal lifetime of seeing the same questions answered in so many ways, I am quite honestly trying to determine how much of my life has been wasted tilting at windmills. Please trust me when I say that I could tax this server with the data I have on what I have done with tempering. I could give you micrographs, graphs and charts, but what is the point if the next poster has a more popular, palatable, or better marketed source to point to? So, in the end, all we really have is our own dedication to the best possible outcome, rather than the reliance on blowhards such as myself.
 
Last edited:
I am afraid that my philosophical digression isn’t really helping answer the initial questions that are the topic of this thread. These are just some questions that have been in my mind for some time, that were probably misplaced here, sorry about that.

To help with the initial topic I will simply refer to this posting, which I wrote just a little over a decade ago. Wow, it didn’t seem that long ago, how did that happen?

https://knifedogs.com/threads/tempering.22969/
 
Kevin R. Cashen said:
Just curious, could anybody expand, in detail, why they . . . So in the end, all we really have is our own dedication to the best possible outcome,
Click to expand...
I think this is a universal quest for all those who want to do their best in whatever field you choose. I've had similar thoughts/questions about various modalities and treatment protocols throughout my 25+ years as a physical therapist. But this is now very much a digression. My apologies, I just didn't want Mr Cashen to think he's alone.
 
Kevin R. Cashen said:
I am afraid that my philosophical digression isn’t really helping answer the initial questions that are the topic of this thread. These are just some questions that have been in my mind for some time, that were probably misplaced here, sorry about that.

To help with the initial topic I will simply refer to this posting, which I wrote just a little over a decade ago. Wow, it didn’t seem that long ago, how did that happen?

https://knifedogs.com/threads/tempering.22969/
Click to expand...
Vey good and helpful article, Thank you.
 
Kevin R. Cashen said:
But after a literal lifetime of seeing the same questions answered in so many ways, I am quite honestly trying to determine how much of my life has been wasted tilting at windmills.
Click to expand...
Amen brother, I feel your pain. After working in the energy industry for over a half century, I am sometimes often baffled at what I see happening in our world, it defies explanation.
Kevin you should know that you've made my journey into knife making a lot more enjoyable and successful as a result of you sharing your knowledge and experience. Your 2012 reference (above) to Tempering is now copied and filed in my library of knife making references (along with many other K.C. references) - Thanks!
 
Kevin R. Cashen said:
Just curious, could anybody expand, in detail, why they follow a specific tempering regimen? Not what they heard somebody else say*, but what is the underlying reasoning is behind the prescribed method? I only ask because tempering has become a topic that is often a source of head scratching puzzlement for me when I visit the internet anymore, and I am just trying to understand.

* Not singling anybody out here, Landes is a good source, I have spent many hours, with lots of adult beverages and even walking local rivers with fishing poles (and even more beverages) with Roman while discussing every topic imaginable. So this question even applies to those who may say "Cashen said..."
Click to expand...
I had to think about this a minute.

All of my heat treating starts with a consensus of source materials that I have deemed reliable based on my ability to replicate or measure the outcome in my own shop, with my own equipment. As far as "recipes" or regimens are concerned, I feel that most of those are ballpark guidelines that most frequently need adjustments to actually hit a specific target.

There are some aspects to heat treating that folks like me will always have to take on faith, like what does tempering really do, and how long do I need to do it and how many times? It's easy enough to replicate a hardness number most of the time. I suppose with careful subjective at home testing a fella could see a marked decline in toughness or edge stability, but, especially for low-experience knife makers like myself, that's real hard to do. So we trust those sources that have steered us with correct information and processes to good and repeatable outcomes. I have no issues then, accepting that the "why" in your sticky on tempering is good information and can be relied upon for the things I cannot test. Not because "Kevin said," but rather because everything else Kevin said was verifiably accurate, and put me on the course to resolving various, specific issues that arise when heat treating.

Philosophical digressions are too far between and underrated in knife making. I'd bet if you polled 1000 knife makers why they make knives, exactly zero would respond "because more stuff needs cut." We make what we make, do what we do, and share what we share to fulfill our desires to make a legacy contribution to something.
 
i used the manufacturer's data sheets, which say two tempers, for some hss steels, there are three... i put the blades in a pre-heated oven, mostly at the lower end of the temper range... for more than an hour, thin blades should be heated through in an hour+... i want razors and kitchen knives hard... i end up in analysis paralysis if someone asks for a tough blade... i do dunk the blades in water between the tempers, and do a cold treatment before and between tempers if i am doing cold treatments
 
@Andre: When you say "cold treatments", what do you mean? Deep freeze? Dry Ice? Liquid Nitrogen? You mentioned doing a "cold treatment" between tempers - first time I'd ever heard of that, what's your reasoning there?

Ken H>
 
You must log in or register to reply here.
Back
Top