Don't feel frustrated, you're almost there...
the point is that I do NOT know what quench to use with what kind of steel,
i answered...
generally, the metallurgy of the steel determines the quench, ie O1 is an oil hardening steel. you could quench it in water but this faster quench might cause cracking whereas an air quench is so slow it won't reach the desired hardness.
the medium determines the speed and different recipes of steel react best to different quench speeds. There is a broad broad array of steels, 100's if not 1000's of them so to know what the right quench is, you need to know what the steel is. this is why mystery metal might be ok for many tasks but is less than satisfactory for heat treating. For complete beginner, they should know that only certain classes of steel can be hardened and that is generally determined the the % of carbon. high carbon and tool steels (like O1, W1 etc - drill rod for example is tool steel, often O1) are common steels you'd heat treat. Mild steels are not directly heat treatable but can be case hardened, a process where the required percent of carbon is added to outer layer via soaking a high temp bath that it pulls carbon out of.
the brine/nail quench was offered as a curiosity, not super practical as the hardening effect is minimal. Generally, you are only quenching high carbon or tool steel.....or case hardened mild steel. This is done when you specifically are trying to harden a part for some application and you would not go about quenching things you made of regular old mild steel as nothing is accomplished.
I don't see a need to make cutters
famous last words
mostly im talking milling cutters and taps, that sort of thing. its not to avoid the cost of buying but to address specialty situations where you can't buy, or are working away on a Saturday and want a left handed tap NOW - easier to spend half an hour on it than wait and pay $50 OR you need some miniature reverse counter bore that isn;t commercially available.
anyway, you may not have encountered the need yet, but they are easy to make so keep it in mind - it expands your repertoire and gives new options to solving problems
better to buy a tool steel and quench properly when you need to harden something
So you know what you've got - if its mystery metal you don't know if it is a steel that can be hardened let along what the appropriate quench is
And what's a proper quench?
the right one for the steel -. Its usually obvious, for us backyard mechanics if you have o1, its oil for example, W1, water....but like anything it can be made complicated, special quench formulas, temps etc. mostly we'll encounter O1, W1 and A1 or high carbon steel that is generally water quenched
That "whatever steel" is an unknown in a number of cases since I haven't a clue what a good chunk of it is. My finances (Remember - VA disability pension that doesn't even come close to keeping up with inflation) don't allow me to go out and buy materials so I almost have to use what's on hand.
Kludge, look, we all use mystery metal all the time, I'm not saying you need mill certs for everything you machine....BUT the subject of the thread is what quench medium to use. Now in this thread however we're talking quenching/heat treating and here it matters - mystery metal is a non starter
It's not much a budgetary problem though - how much of what you're making is hardened? if you right now are heating up every piece of steel and quenching it you're wasting the VA pension on fuel - you only quench what you need hardened and you only harden certain kinds of steel. In the home shop this mostly means the odd cutting tool or more rarely an engine part. Mostly home shops avoid making every fixture/tool from tool steel the way industry does because most homeshops don't have the grinding facilities to deal with the hardened stuff nor the wear and tear to require it in the first place. Sooooo, its much to do about nothing - when you need something hardened use a piece of O1 drill rod and take comfort that you'll not need to do so very often
at the rist of over complicating things, The other approach to get hardened parts that works well is casehardening mild steel like using Kasenit. doesn't' get a very deep case, but it does work.
John, as you surmised, I took it that you were referring to the thread subject of quenching/heat treating.
Imagine a total newbie that is taking his very first steps into producing his first runner, only to be told that cylinder pivot pins should be made of such and such a grade of oil hardened silver steel. This poor builder just might say, 'Well this is not so easy, I will give up now', instead if given a bit of information as I did, he just might have a rethink and carry on. The first engine, after maybe a couple of hours running will be consigned to the workshop shelf. The modeller will then go on and on making bigger and better engines, and start to understand the meaning of stressed components and wear factors.
that's the core of it, we're both trying to help the newb but have different tacts on it. Your attitude seems one of making things more accessible to newbies by ploughing a lot of stuff to side - i get why this will help some and what you are trying to accomplish. I come at it from a different tact, if the plan calls for something hardened, the best thing is for one to learn how to make something hardened...and they more they pay attention to the details the better results they'll get. For most published ME designs there is a fair bit thought behind them with the author having good reasons for these choices and the process are with the home shop builder in mind.
I'd take your proffered scenario and say its nothing to learn how to heat treat those pins, the builder will gain confidence and the result will perform as expected leading a happy satisfied builder to go on to make bigger and bigger engines
. same goal line, different game plan to get there. Its my view that none of this is hard or beyond anyone's reach, just requires a desire to learn and source of info and knowledge