Do I really need to heat my quenchant past room temp?

[jcoon8283]

Ok, so I am using parks#50 to quench my 1095 in. Do I really need to heat it up from room temp before I quench the knife? The literature that came with the oil from parks mentioned it was ok to use at room temp, but I just read on another forum that if it is not heated some form of vapor jacket is formed around the knife being quenched giving undesirable results. I have been quenching at room temp (75-80 degrees) and it seems to me that the knife if ok, but, I am new at all of this so I am unsure. Thanks for the help!!!

[Ray Rogers]

Most oils work better at 125 - 150 F but I've used them at room temp (much less than your temp) and seemed to work OK. The problem with subjective judging of 1095 is that almost anything you do to it will seem like it worked. My first 1095 blade was heat treated over a hole in the ground filled with 40 pounds of Kingsford charcoal and it seemed to work. Then, a bunch of years later I put that blade under a Rockwell tester and found it was in the mid-40's. You probably did better but the point is that 1095 can fool you pretty easily. It's best to use the oils as specified and most recommend warming up before use ....

[WBE]

Parks #50 is formulated to work best at about 100?, up to 120?. and down as low as 50?. Those temps are manufacturors recommended temps. According to the makers, you have a wide range of effective cooling. Most, or all other oils are usually recommended to be at around 130?. There is a chance of cracking your blade above 100? with #50. Of course, using 1095, there is always a chance of it cracking.

[Doug Lester]

Be careful, one maker on one of these boards heated his Parks #50 up above the recommended temperatur and found out that it had a rather low flash point. I can't remember how hot he said that he got it but it wasn't up to normal cooking temperatures. It's not vegetable oil.

Doug

[jcoon8283]

Looking at the technical data sheet that I got with the parks it says and I quote "The recommended operating temperature range is ambient to 120 degrees F. 50 Quench Oil is as effective at 50 degrees F as it is at 120 degrees F because of its low viscosity." So I was pretty confident that I was ok from the manufacturers instructions standpoint. But, I saw the post about the "vapor jacket" forming and it got me a little worried and I thought I would ask. So if 1095 can fool so easily how do I find out if it turned out like it was supposed to. If you look at my post "how long should my edge last" just a few clicks down from this one you can see how I heat treated my knives. I tried to get it as "cookbook" as possible, but I am new at all of this, and don't really have any good knives I can test the ones I made against (part of the reason I began this in the first place). I did try the edge test with some soft steel wire and found the edges to be a little soft after tempering, so I retreated them at 1475, then tempered at 420 1st cycle, and 435 for the last two, and they held up against the wire. I guess I am just a little nervous about all the stuff I read on 1095, how hard it is to ht, and everyone has a different recipe to do it that's the "right way" to do it. I really don't want to let a knife go without knowing 100% I did the ht right. So I guess being a newbie and not knowing much, how do I find out? Sorry for the long winded post, thanks for the help!!!

[Doug Lester]

It will depend on 1095. I've had problems with the 1095 that I got from Admiral Steel; it was one of the reasons that I stopped using it. Reports on the 1095 that The New Jersey Steel Baron carries is that it is rather easy to harden.

For testing, I start out with the soft steel wire before I put a handle on the blade. After I put a handle on it I chop on a 2X4 for a while to see if it keeps it edge or I cut up a lot of strips of cardboard and see if it still will shave hair. With larger blades I cut free standing bottle of water to test the geometry. I want the blade to cut through at least one bottle. If it leaves the bottom standing with water in it, all the better.

Doug

[jcoon8283]

The 1095 I got was from Jantz.

[Ray Rogers]

There is no single "right" way to HT most of these steels. There will be some variance because of the exact composition of the steel (not all 1095 is precisely identical) and some variance according to the intended purpose of the knife. For instance, the HT could be best for edge holding but the blade might snap relatively easily. That actually would be fine for a sushi knife but not acceptable for a general purpose field knife. Or, the HT could allow for extreme toughness that you might want in a survival knife even though you must give up some edge holding to get it.

The bottom line is that you need to test your blades. Test them hard, test some of them to destruction, and test them according to the use you intend for that knife. If they out perform any off the shelf knives you have and if you feel satisfied with the performance if you were to use the knife yourself for its intended purpose then you have the HT about right. That's it, that's all there is. To go any further than that you'll need access to a metallurgical laboratory ....