Thread: Blade Steel types for razors

i have parks 50 also and it great stuff. i cover all my oil hardening stuff (slow oil steels i interrupt the quench) that and the Al plates for quench of air harding steels is mostly uneventful

tho i did warp 2 razors the other day in 1095

Originally Posted by randydance062449

The heat treating for 1095 is a bit picky and do not use water as a quench or you will learn what a cracking blade sounds like. Use a fast oil as a quench.

While a fast oil is solid advice, heated water is not out of the question. I've only broken one out of ten razors made of 1095 that were quenched in water. And in fact the one that broke, should not have, it was my fault.

But then again, I leave a little more material on the edge so that they have a better chance of surviving, I just have to spend an extra 5 minutes grinding that little excess off which isn't a big deal.

Originally Posted by Russel Baldridge

While a fast oil is solid advice, heated water is not out of the question. I've only broken one out of ten razors made of 1095 that were quenched in water. And in fact the one that broke, should not have, it was my fault.

But then again, I leave a little more material on the edge so that they have a better chance of surviving, I just have to spend an extra 5 minutes grinding that little excess off which isn't a big deal.

You can't be saying just plain ol' heated water, can you? Brine, I can see, but plain water would allow the creation of a vapor jacket around the blade, slowing down the quench and rendering it ineffective for a steel like 1095 that needs a near immediate quench. I think you have something like 1 second to get it cooled off from quenching temperature or it won't get fully hard.

Yes, I mean plain water. For 1095 you have ~1 second to get the blade down under ~900 degrees and much more time than is necessary to get it down to room temp. With my current procedure the exposed portion of the blade stops sizzling in the water within .5 to 1 second, the back of the blade follows at around 4 seconds (clay treatment).

I've yet to have a blade come out of the water any softer than a file, and they break like glass if hit with a hammer (did this on a test piece of 1095 put through my usual forging, normalizing, heat treating cycle, before tempering).

Salts and surfactants are sometimes necessary for lower carbon content steels, but it is not uncommon to use plain water for the higher carbon versions.

Originally Posted by Russel Baldridge

Yes, I mean plain water. For 1095 you have ~1 second to get the blade down under ~900 degrees and much more time than is necessary to get it down to room temp. With my current procedure the exposed portion of the blade stops sizzling in the water within .5 to 1 second, the back of the blade follows at around 4 seconds (clay treatment).

I've yet to have a blade come out of the water any softer than a file, and they break like glass if hit with a hammer (did this on a test piece of 1095 put through my usual forging, normalizing, heat treating cycle, before tempering).

Salts and surfactants are sometimes necessary for lower carbon content steels, but it is not uncommon to use plain water for the higher carbon versions.

You learn something new every day. If you say it works for you, I certainly can't dispute it.

some good information here. the only thing i didn't see about choosing a blade steel to make knives with is wether you planned on heat treating the steel yourself or have someone else do it. If you plan on heat treating it yourself and don't have a good oven yet then stay away from stainless. Carbon steel can be heat treated at home with very little money compared to stainless if your not going to go buy salt pots, or ln dewer's. If you want to quench in oil and do it the old fasioned way carbon would be the way to go. Then you have to figure in your wallet and see what's in your budget for steel types realizing that the more exotic alloys cost more, not just in intial cost, but also in belts and other equipment to work it. Even if you don't have a good oven yet you can still work the stainless and send it off to be heat treated by people like paul boss, until you get your own oven.

Originally Posted by Joe Chandler

. but plain water would allow the creation of a vapor jacket around the blade, slowing down the quench and rendering it ineffective for a steel like 1095 that needs a near immediate quench.

It's worthwhile to discuss the vapor jacket problem. It might cause a large piece of steel, say bowie knife sized, to have just enough of a delay that the heat treatment could be uneven (non uniform). But with the conversion of martensite from austenite running at the speed of sound (Verhoeven), when compared with a half to one second, as Russell points out "when it stops sizzling", the vapor jacket phase is very slow. The martensite's already done despite the bubbles. And unlikely to be much of an influence in a razor sized section of steel because there is significantly less mass to cool down across a much thinner section.

Even oils will have vapor jackets from the oil burning and flashing into smoke and they are considered slower quenches than water. Nobody seems to worry about the problem in an oil bath, but it keeps coming up with water because if the timing is right, there could be an influence.