Heat Treating a thick machete in 5160

hathegkla · May 27, 2010

I'm planning on making a very heavy chopper/machete in 5160, the blade will be about 3" wide, 1/4" at the spine and overall 30" long. I've never tried anything bigger than about 14" and I'm wondering how I should go about this.

I have some "11 second quenching oil" and was thinking of just building a tank out of a big metal pipe and quenching tip first. but I've also heard of edge quenching in water or brine with a teapot like they do with kukris. is this dificult to pull off? are there any videos of this out there?

can you brine quench 5160? I've heard some people do it but it seems risky.

unky_gumbi · May 27, 2010

I tried a brine quench on 5160 today, small piece just as an experiment and I got 4 nice cracks. I don't have a thermocouple on my little coffee can forge so I can't tell you what temp I was at, I just know that I was able to melt salt in it. My brine was preheated to 120F. I tried again with canola oil and had no cracks the piece was hard enough to break when slapped against a concrete step.

I have no hard facts for you I am just playing around testing some things out, so maybe some of the more experienced makers will chime in and share some of their wisdom with us. In the mean time I am heading back out side to play and experiment some more, nothing says learning like trying new things, luckily I have a few scrap pieces to play with

Bill Armstrong · May 27, 2010

I tried the tea pot quench a while back and it came no where near cooling the blade (kukri) fast enough to truly harden so I torch heated the edge again and oil quenched and it got plenty hard!...then tempered it back by slowly heatin the spine and watched the colors for a dark straw on the edge...it really holds an edge now!

JasonSCarter · May 28, 2010

Guys for the most part, unless it says 1095/W1/W2 DONT WASTE YOUR TIME WITH A BRINE QUENCH! look up TTT charts for 5160 (or any steel you'll be working with) you'll see they can use a nice slow oil for quench... Mineral oil is the old school quench oil, but McMaster Carr 28second quench oil is great for this steel and cheap too... I'm all for experimentation, but what was the hypothesis you were trying to answer? I apologise for the jerky tone but I just dont understand why you'd abuse good steel like that. when the stickies at the top would of answered this question 7-8 times at least.

Jason

Sparljo · May 28, 2010

Theres nothing wrong with experimentation.

It sounds like all of the posters sofar are aware 5160 is an oil quench steel.

unky_gumbi · May 28, 2010

JasonSCarter said:
Guys for the most part, unless it says 1095/W1/W2 DONT WASTE YOUR TIME WITH A BRINE QUENCH! look up TTT charts for 5160 (or any steel you'll be working with) you'll see they can use a nice slow oil for quench... Mineral oil is the old school quench oil, but McMaster Carr 28second quench oil is great for this steel and cheap too... I'm all for experimentation, but what was the hypothesis you were trying to answer? I apologise for the jerky tone but I just dont understand why you'd abuse good steel like that. when the stickies at the top would of answered this question 7-8 times at least.

Jason

Don't worry about wasting good steel, or me taking offense, they are just little pieces of scrap, nothing is big enough for me to make anything with

I tried brine only because the OP mentioned it and no one had answered him yet. I too had heard the rumors that you could use brine to quench 5160 and I was just out to proof it wrong, after that it was just experimenting with my coffee can forge and different home quenches. I have 2 more pieces of 5160 scrap and a couple of pieces of O-1 to test with, but its pouring rain to day so no playing.

hathegkla · May 28, 2010

I will be using a digitally controlled kiln to heat the blade so accurate temperature isn't a problem. I was just trying to avoid bringing 5 gallons of quenching oil over to my parents house (my furnace isn't big enough). I don't want to risk cracking the blade so I think I'll just use my 11 second oil in a big pipe.

I know 5160 is a through hardening steel but could I get a differential temper by using clay and quenching in 11 second oil? I'm not looking for a hamon, I just want a tough blade.

hathegkla · May 28, 2010

unky_gumbi said:
Don't worry about wasting good steel, or me taking offense, they are just little pieces of scrap, nothing is big enough for me to make anything with

I tried brine only because the OP mentioned it and no one had answered him yet. I too had heard the rumors that you could use brine to quench 5160 and I was just out to proof it wrong, after that it was just experimenting with my coffee can forge and different home quenches. I have 2 more pieces of 5160 scrap and a couple of pieces of O-1 to test with, but its pouring rain to day so no playing.

well thanks for trying it out! I knew it probably wasn't a good idea I've just heard people talking about kukris being edge quenched in water. I guess I bought that bucket of oil for a reason right?