Sign in to follow this  
MikeTausig

Advice on differential HT with 1095

Recommended Posts

Hi folks. 

I wondered if anyone on here has tried a differential heat treat with 1095, and if so, what was your process?

 

I forged a small skinner (8.5” OAL, 3” blade, 1/8” thick) from 1095. I’ve worked with 1095 many times and the HT can be tricky. Well, tricky when compared to 1084. Suffice it to say that I understand the (correct) standard HT process for 1095. With this current blade, I have file work along the spine, and while I could use whiteout and do a standard HT, the thought of doing it differentially came to mind, thus eliminating any scale on the spine. I also wouldn’t mind having only the edge hardened for this particular blade.

 

The advice I’m looking for pertains to soaking temps. 1095 typically needs a soak above critical. This is not a problem when I use my forge, as I set the temp for where I want it, then let the metal soak. When doing it differentially, I’m afraid I won’t have an accurate temp for the “soak,” if that makes sense. I would be using a gas torch for the heat source. Judging temps by color is fine for me in very general terms, but I don’t know that I can dial in a specific temp by sight.

 

I’ve done differentials with 1084 many times, as the HT process is amongst the simplest for that steel. I have not tried it with 1095, and am hoping for some advice before trying it. I’m fine with the advice being “1095 does not do well with diff HT,” and if that’s the case I’ll do it the standard way. 

 

Thanks in advance. I think my info is specific enough, but I’d be happy to provide further info if needed. 

 

Cheers,

mike

Share this post


Link to post
Share on other sites

What are you talking about? Heat treat is a broad term, I think you are you talking about hardening but your title is  misleading, I already covered both differential hardening and differential tempering the Heat Treat pinned posts

Share this post


Link to post
Share on other sites

Hmm...I thought I was pretty specific. I figured the term “heat treat” was pretty specific in the knife world, as it refers to austentizing and conversion to martensite- ie heating and quenching. Let me try again. 

 

I want to do a differential heat treat on 1095, opposed to a full heat treat of the metal. So...that is heating only the edge of the blade to the appropriate temp, versus placing the entire piece in my forge. 1095 must “soak” at above critical temps (multiple times) in order to allow grain conversion and stress redux before quenching, so I’m trying to identify the best process for achieving this by only heating the edge, opposed to fully heating the entire piece  

 

I read the pinned post you made while searching, and it is a very good intro to what occurs metalurgically when heat treating steel. It does not, however, address heat treats for specific steels. The heat treating process for 1084 (as an example) is much different than the one for 1095, as I’m sure you’re aware. 1095-specific discussions only address full HT, not differential  

 

If I missed the thread or responses that are specific to 1095, could you link the correct place? I did multiple searches for this specific question, read about 40 threads, and none of them referred to differentially treating 1095. 

 

Thanks man.

Mike

Share this post


Link to post
Share on other sites

We cant communicate when we dont use the same established terms to mean the same thing.  The process called heat treat is any temperature change used to effect changes the steel,  as Forging itself is a heat treat,  it is hardening, it could also mean tempering, or Cryo treatments, and I cant wait to hear how you only heat and soak the edge and not the rest for hardening

Share this post


Link to post
Share on other sites

Mike, as Steve has said, "heat treating" is a generic term that can include annealing, normalizing, quenching, tempering, and a few other operations.

With regard to your specific situation, if I were doing it I'd protect the spine area with clay, whiteout, or something else to inhibit scale formation, soak the whole piece at the appropriate time and temperature, quench the whole piece, then do a differential temper to keep the edge hard and soften the rest of the blade.  There may be a better way, but that's how I would approach the situation.

Share this post


Link to post
Share on other sites

My apologies. You are correct. I took for granted that in a knife section, folks would interpret the phrase “heat treating” as what we do in any series of heats above critical leading to a quench (in whatever medium the Smith is using) in order to harden and make a blade. If my terminology was unclear, I apologize. As I said, I took for granted that in a knife section, folks would know the reference, as is the norm in the ABS or ABANA. 

As for your final comment, I hope I’m not misreading it, but it sounded snarky. Differential heat treats are commonplace in knife making, where only the edge is hardened, leaving the spine “soft.” This is of particular use for choppers, or any knife that might need “flex” or will revive blows to the spine etc. I certainly don’t want to offend anyone, as i am here for the purpose of learning and offering advice when possible. I merely wish to find advice on a differential heat treat (ie hardening of only the edge) for 1095. I have successfully differentially hardened countless blades, but none were with 1095 due to the more extensive austentizing and quench process  

 

Thank you, and much respect. 

Mike

Thank you buzzkill. And yes...I totally get the “generic” use of the term. Having surfed the online knife groups for so long, when someone references HT, it is about hardening, whereas if they are annealing, they use that specific term. 

I would prefer not to do a differential temper, as it is not needed and for this specific piece don’t want the undo stress. This question might be better served for the ABS member site, so I’ll ask over there. But I greatly appreciate yours and Steve’s responses.  

 

Cheers,

Mike

Share this post


Link to post
Share on other sites

Differential hardening is common, but we heat the entire blade, slowing down the spines cooling,  as I already stated in the pined post you said you already read, I dont know of a way to only heat the edge and soak it with out heating the rest of the blade during that 5 minute soak process.

You still want to mis-use the all inclusive term of heat treating for one specific area of heat treatment is the problem here. also a  misunderstanding of how to do it

 

Share this post


Link to post
Share on other sites

Ok, well thank you. I’ll take this to the ABS member forum, where terminology won’t be an issue and the process is better understood. 

 

As an FYI, the process is done via oxy/acet torch only along the edge, in order to raise only that portion above critical. Not the entire blade, as you claim, in my lack of understanding of “how to do it.”  It was taught to me by a master smith, and has been an invaluable tool in my arsenal of hardening techniques, along with countless other smiths  

 

Thank you all the same, and much respect. 

Mike

Share this post


Link to post
Share on other sites

really?  once again you  mis-read things, you are not very teachable.  Ask your ABS friend.   I said heating only the edge with out heating the entire blade is not likely, when your soaking the edge at critical, it will bleed over and heat the spine, even if it is in water, for that long the heat will bleed.  Also 1095 is not the best choice for differential hardening process because of the needed soak times

 

Share this post


Link to post
Share on other sites

You just had two people explain to you that the phrase heat treating has wide range of meaning and you can not seem to understand that. Instead you want to insult them and say you know much more than they do.  There is no longer a reason for this thread to continue, this thread is closed.

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this