Ht 5160

MikeS

Active Member
Hey folks,
i am a rank newbie! Need some suggestions what quench to use on 5160 steel. The majority of my blades are smaller to medium size. Side note I have had heck of a time of finding Parks 50. Anyone using McMaster Carr either 11 sec or 28 sec quench oil for 5160?
Thanks Mike
 
Hey folks,
i am a rank newbie! Need some suggestions what quench to use on 5160 steel. The majority of my blades are smaller to medium size. Side note I have had heck of a time of finding Parks 50. Anyone using McMaster Carr either 11 sec or 28 sec quench oil for 5160?
Thanks Mike

Hello Mike, the Parks #50 is rather pricey and harder to find but the good news is that you don't want it for 5160 anyhow. Any medium speed oil will work well with 5160 so the McMaster 11 second will be good. You may want to consider branching out with other choices for you size of knives however. Smaller to medium sized blades usually work best with higher abrasion resistance and edge stability via strength. 5160 has a greater emphasis on toughness which works best for larger knives used for chopping and cleaving cuts and will not have the same edge holding characteristics of a steel with a little more carbon.
 
Kevin,
Thanks for writing back. Good info on the quench oil for 5160. I understand what you are saying on the 5160 in smaller to medium size blades. My reason for starting there was pure economics. I have a large amount of 5160 just laying around my shop. My thought was if I goof up a grind it doesn't cost me a pint of my blood. I just chuck it and say its just learning. As far as smaller to medium size blades what about O-1, 1084, 1095. Any thoughts or suggestions? Any better ideas?
Thanks again, it really helps
Mike
 
As far as O-1 goes, it's a high carbon lowish alloy steel that can use a soak at around 1475° for 10-20 minutes to dissolve the carbides and limit grain growth. That pretty much requires a regulated high temperature oven which might require an update to the electrical service. 1095 is a high carbon "plain" steel. It can be a little fussy and though it can be heat treated in a gas forge it really benefits from a regulated oven too. 1084, 1080, 80Crv2 are good beginner steels (good for old timers too). Not much in the way of extra carbon to form carbides, other than cementite or iron carbide, you can put all of the carbon in them into solution with little worry about retained austenite and, if you don't get crazy heating it up, grain growth is manageable.

Doug
 
Doug,
Thanks for the input.i am working on a heat treating oven as we chat. So that's not a problem.i am doing my homework on 80Crv2 steel. Any comments on it?
Thanks
Mike
 
I haven't actually used 80CrV2 myself but a lot of the 1080 out there seems to be close to it. The added chromium will give it a bit more hardenability and the little bit of vanadium that it has will help put a little bit of drag on the grain growth at higher temperatures without causing red hardness.

Doug
 
Mike, the good news is that none of these steels will cost you a pint, I have done a few cost analysis on knifemaking materials and by far the cheapest part of making any knife is the steel, even the epoxy you glue the handle on costs many times more than the steel in the big picture. So feel free to play with those alloys you have been wanting to try, some are really nice.

Speaking if which, O-1, 1084 and 1095 are all winners. In the size range we previously discussed theO-1 and the 1095 will really shine; I would also suggest W-2 and W-1 if you can find them. O-1 is a classic which set the standards for fine cutting tools. In my lifetime, every year I have seen new steels that are supposed to the ultimate in making a knife out of and are all the rage, and yet in no time there is an all new flavor of the month that has replaced the last fad. In all of this fad frenzy there has still always been O-1 standing there as solid as a rock. Why? Because O-1 is not hype or a fad, it is the real deal and has stood the test of time as a quality cutting tool from a simple alloy, it is boring because it just is and doesn’t need all the PR.

1095 has gotten a bad rap for two reasons, it can’t be worked like 1084 and those who don’t understand this blamed the steel for their lack of understanding it, and the other reason is that there were a couple of bad batches that reached the knifemaking market via certain suppliers that cause folks to judge all 1095 because of it. By far the cleanest and finest quality steel I ever worked with in my career was anold batch of European 1095 I once got.

1084 is the friendliest steel to work with bar none. It will make a fine general use knife under almost any conditions regardless of the maker’s skill level. It won’t make a great chopper like 5160, and it won’t keep up with 1095 or O-1 in fine cutting edge retention, but it will make an excellent knife in the Goldilocks zone between the two.

W-2 is the legend among simple carbon steels for fine slicing edge retention if you can get it, but in the world of modern alloys it is fast becoming extinct. I think O-1 will hold its own against W-2 and 1095 but only if you have the temperature controls to unlock its potential, one of the other reasons that O-1 was never raved about was that most people never really nailed the heat treatment. So if you have an oven I cannot recommend O-1 enough. If you only have a forge, 1095, W-2 or 1084 will get you the most bang for your buck. And if you have temperature control don’t lose any sleep over grain growth. Grain growth is what I call the boogeyman of bladesmithing, much thesame way parents get their kids to stay by the fire at night or the boogeyman will get them, when really there is nothing out in the darkness to fear if you know the way. Grain growth is like burning the steel, you only really need to worry about it of you lose control of your temperature, but it doesn’t take long at all for folks to develop the skills tonot burn steel, and then it is completely avoidable. The main difference between the two is that burnt steel is ruined, but any grain size can be fixed with a couple of quick cycles.

80CrV is a new name on the block, but actually an old familiar face under a new name. It has some interesting quirks due to its annealing processing that has an odd range of HT temperatures being reported by people. I have yet to work with a sample of the problem batch to determine what the issue is, so I must reserve comment at this time as one of my rules is to not guess or lead people astray with my opinions but instead wait until I can offer some solid facts

 
Last edited:
Kevin and Doug,
Wow lots of great info in real short order. This really is helping me out a bunch. The only problem I can see is that making knifes is addictive and way too much fun!!
Do you guys think the McMaster quenching oil (11sec) would work on the O-1? Do you think it would on the other alloys we have talking about?
Mike
 
I've thought about this a bit and I'm not sure that I'd call grain growth a bugaboo used to frighten beginning knife makers. Not infrequently a knifemaker will post pictures of a broken blade and the grain size is large. Admittedly that does not mean that he made a useless blade, except for the fact that he broke it. It means that he could have made a better blade that wouldn't have the brittleness problems associated with excessive grain size. Kevin is right that with proper heat control that grain growth is over rated. Tests have shown that you could probably take a blade made of O-1, or like steel, and soak it at 1475° degrees, or even a little higher, for an hour and not have significant grain growth. However, heat treating with a gas forge and trying to soak for 10-20 minutes it could be very easy to get well above that range without realizing it and end up with large grain.

I guess that you'll have to count me in the group of people who have had problems with heat treating 1095. Of course I was using Goddard's Goop to quench in at the time.

Doug
 
Mike, the O-1 will work even better with the 11 Second oil than the 5160 will. Doug, you are correct that grain growth is a serious problem when it actually occurs, edge stability and impact toughness drop to worthless levels, it is really nasty, so it is not a boogeyman in that it actually exists, but it is not really a threat once one has control over temperature.

For some time guys who work in forges have been leaving the impression that grain growth is an ever present danger ready to leap out and get you whenever you drop your guard for a second, but this is mostly because they use a forge, or a 6,000F torch flame to heat treat. In reality grain growth is not dependent on the phase of the moon or not measuring every heat to the fraction of a second, it is temperature dependent. Once you have even moderate control over temperature grain growth should no longer be a problem.

Grain growth phobia seems to be the last vestiges of the edge packing myth, i.e. only the hammer of skilled smiths, or some guys "speicial" techniques, have the magical powers to control grain size, so I must apologize that I am rather proactive in dispelling it. Recrystallization works in a very set and predictable way. First, as your heat nears Ac1, you will begin to nucleate tiny embryonic seed grains in the existing grain boundaries. Then when Ac1 is achieved the allotropic shift occurs that allows those new guys to form into actual grains by absorbing the old grains. Equilibrium is the magic word since it is all driven by very basic physics, it is a process of going from high energy to a lower energy equilibrium. The nucleation will be at points of higher energy in the matrix and will feed off that energy until equilibrium is achieved, at this point you now have a whole new set of grains. This new set of grains will have undissolved carbide at their periphery keeping things stable and defining the grain boundaries, as well as other particles from the steel making process, this is why you have not one, but several critical (arrest) temperatures, one lower (Ac1) and three higher (Ac2 for the Currie point, Ac3 for hypoeutectoids, and AcCm for hypereutectoids). Ac1 is the recrystallization temperature, but for a hypereutectoid AcCm is the point where all those extra particles are dissolved and the grain is free to grow as temperature overcomes equilibrium. But with a hypereutectoid you are going to do even worse things for edge stability than enlarged grain before you reach AcCm.

But once equilibrium is achieved, it is exactly that, equilibrium, and it will take greater temperatures to overcome it. When you set an oven that can hold a precise temperature, you can maintain equilibrium and grain size, but in a forge you can lose concentration and quickly spike the temp 100F without even knowing it, and so those who use unregulated heat sources often get a bit more gun shy of grain growth. The other thing that adds to the confusion is that I know of very few smiths that actually have the means of measuring grain size properly. Instead almost all who say they are observing grain size are doing it via fracture methods. The problem here is that it is subjective to interpretation. Fully hard steel fractures in a different mode than steel with mixed microstructures/phases. With a little pearlite mixed in, or even with a little tempering, the fractured grain surface will have a rougher and coarser look. Over my years I have watched many veteran bladesmiths show the “smoother” look on the edge of an edge quenched knife as proof of edge packing, despite the fact that it was the heat treatment, not the hammer, or even grain size that accounted for that appearance.


So you are correct that grain growth is bad and a real threat to knife quality, but like burning the steel while forging, it is easily avoided with a little care. If you slip some O-1 into a 1475F oven, that oven is going to have to malfunction in some way to enlarge the grain, but if you heat the same blade with a torch all it is going take is a split second of letting your mind wander and grain growth is a very clear and present danger.
 
Doug,
Good points from both you and Kevin. O-1 is sounding really good. I have an Evenheat oven heading my way with an electronic controller. What do you guys think of the type of quench oil for O-1 steel. I have Mcmaster Carr 11 sec. I tried some 5160 in and it really hardens it.
Mike
 
Doug,
Good points from both you and Kevin. O-1 is sounding really good. I have an Evenheat oven heading my way with an electronic controller. What do you guys think of the type of quench oil for O-1 steel. I have Mcmaster Carr 11 sec. I tried some 5160 in and it really hardens it.
Mike
O-1 in 11second oil should work well, i have been using Fuchs 12second for some time and have had very good results. One of the main reasons I like O-1 is the choice of size, 1/64" to 3" thick, 1/8" to 16" wide, 18"or 36"long, the thinner you go, the less the soak time required, with 1/32" i soak about 7minutes at 1475F(800C is what i use because it is easier to see) 5/32" about 15 minutes. once you have your furnace, keep a log book of everytime you use it so you have a record of what you did. the idea being once you know what temperature and time works best with a certain steel at a certain thickness, you can repeat your results. if you shop, you can find precision ground flat stock(PGFS) in O1 for very reasonable prices. PGFS is industrial gradeO1 tool steel made using ISO9000 quality control and is ready to use right from the wrapper. if you are doing stock removal, place the finished blank in a 1475F furnace, soak for required time, quench, clean and temper. when the HeatTreat gods are smiling on you, you can see quenched hardness of Rc65. O-1 seems to be best used in the Rc61-63 range where it has good toughness and hardness(https://www.crucible.com/eselector/prodbyapp/tooldie/ketos.html) this link has over 200 sizes available http://www.ebay.com/sch/m.html?_ssn=toolandequipsales&_from=R40&_sacat=0&_nkw=oil+hardening&_sop=15.
 
Last edited:
Mike, I hope you enjoy your Evenheat oven. In heat treating there is no such thing as too much heat control but, as both Kevin and I were expressing, you can really mess things up with too little. Scott also gave you some good tips on getting the most out of your oven. As far as which commercial oil to use I"m afraid that I've never gotten away from peanut oil. That may do well for O-1 but I have no experience with the combination being that I don't feel that steels with up to around 1% carbon in them can really be expected to give consistent results using a gas forge to heat threat with.

Doug
 
Mike, I hope you enjoy your Evenheat oven. In heat treating there is no such thing as too much heat control...

Doug


The quote of the day, Amen! I had a young guy in my shop not too long ago who was watching me set up a thermal schedule that was different from what he had seen me or anybody else use. I explained that it was because it was designed to take a percentage of cementite out of solution and arrange it in the grain boundaries so I could do some metallography of austenite grain size analysis and something you would never want in knives. Wide eyed he asked if I was messing with him and if I could actually do that. I said it was no problem when you have heat control. A little later he also had a hard time wrapping his mind around things when I told him that I prefer to only put .7% carbon in solution and leave the other .2% in fine carbides, and thus avoid significant plate martensite formation and avoid retained austenite issues altogether. Once again, beyond comprehension in a forge, but just a matter of the right numbers with a controlled heat source.


Folks who dismiss the advantages of tight temperature control, because their forge or torch does just fine are really a very good example of the souls in Plato’s allegory of the cave, they cannot possibly miss what they have never known, but a whole new world awaits if they have the desire to step into it.
 
Kevin, Doug, Scott

good info and advice.i am sourcing some and I found some good pricing on O-1. Also it doesn't cost a "pint". The points on the heat treating oven are noted and well taken. Again thanks! I just got my heat treating quench oil today(McMaster Carr 11 sec). I'm still waiting on the evenheat oven and controller. I also got little ceramic jig for holding blades. I've been practicing my bevels on odd and ends of mild steel. While not perfect I can tell a big improvement. I've ground a couple of small blades out of the 5160. While not perfect again I don't have to hang my head down. Again like I said earlier the only problem with making blades is that it is addictive and way too much fun!! Kevin, I'm not a metallurgist but I'm a pretty decent chemist, I don't understand the finer points of the heat treating yet, but I'll get there, especially with coaching I've been getting here. Now I have an idea of what I don't know (which is considerable) now I need to some studying and homework. So that being said I may be asking you folks more questions along the way. Eventually I want to forge blades. But first,k baby steps.
Mike
 
... Now I have an idea of what I don't know (which is considerable) now I need to some studying and homework. ...

I have always said that there are three levels of knowledge. The first is when you know nothing about the subject, next comes the step when you know everything, but the final step is when you finaly understand and know how much you don't know.
 
if you are interested, the web is full of texts on metallurgy and heat treat. here is one published by ASM international http://www.asminternational.org/doc..._TOC.pdf/07678056-70c3-4c2f-910d-33fc7e8dd2c5. here is version of Dr. Verhoeven's book http://www.sabladesmith.org/wp-cont..._Steel_Metallurgy_for_the_Non-Metalurgist.pdf.
for me, steel heat treat is an equation with many variables, with the outcome being a useful piece of hardened steel. the more variables you eliminate, the easier the outcome is to reach. so by using industrial quality tool steel, in a furnace with good temperature control, quenching in a known(tested?) quenchant preheated to recommended temperatures, using the same soak time and temperature every time for a known steel and thickness, tempering in an oven with good temp control you should be able to achieve consistent results.
 
Back
Top