Chronos silver steel, water or oil quench?

Edited By Nicholas Farr on 13/10/2010 00:16:09

Reference " peeing " in the quenching tank, years ago was told the story of a metal treatment shop in a large engineering concern, a new manager was appointed and as part of flexing his muscles he decided that the metal treatment shop , particularly where heat treatment took place, had to be cleaned up as it was like a tip. He organised a blitz of the area and in the corner was a tank containing murky not very pleasant smelling liquid which he had emptied and then scrubbed clean. It soon became apparent that the components that were heat treated where significantly below the standard usually achieved, an enquiry took place and the elderly gentleman who worked in the heat treatment area said that they would not be able to attain previous hardness values because the tank that they had emptied and cleaned out had not been emptied for years and he always peed in it and this unsavoury brew was the reason for the high hardness values they used to achieve.

Dave

The preferred method way back was to quench in water that had a layer of sperm whale oil floating on top.

Rik

I believe they used Dragons blood, i`ll let you decide if it is myth or not! Or was that Damascus steel from Persia, i recall something about `the urine of red headed boys ` as well

Edited By mark smith 20 on 11/11/2017 10:25:27

I visited a working forge some years ago and the blacksmith told me he kept a bucket of horse pee for quenching just about everything that needed quenching.

Back to peeing again.. It's true that urine contains a lot of nitrogenous compounds, but over time these would largely be decomposed to ammonia and then lost. However it also contains small amounts of phosphates, and these are more stable so would tend to accumulate. Perhaps this has something to do with its claimed effectiveness? The problem, of course, is that any concept of compound formation from nitride or phosphide would be confined to a thin surface layer, and lost as soon as the item was finish ground.

I think I will continue to use a jar of water.

If memory serves then it's stale urine where urease bacteria split the urea to nitrates. Barrels of urine were collected in London and shipped up North for the dye industry too. For gunpowder the nitrate crystals skimmed off would be mixed with lye (all the woodburning ashes were kept and then water allowed to seep through them - also for soap making). In jamaica for instance Bat guano from caves was the urea/nitrogen source. Charcoal and sulphur thn added and the mixture ground together. the fineness of the grind affecting the burn rate.

It does make one wonder whether enough stale urine in the quench might have a nitriding effect??

These legends abound. Apparently, the best pee comes from a red headed lad although it was said that the finest swords were made by quenching them in the belly of a captured opponent (ugh!). I guess there's a grain of truth in them, possibly harking back to Andrew's comment (from 2010 ) about using brine.

Then, there's the tale of the factory whose heat treatment went to pot because the foreman lost the orange peel he used to set the furnace temperature.

Rod

I did my apprenticeship in South African Sugar Mill and the blacksmith shop had a huge tank of pure whale oil for hardening purposes.

Bit hard to get hold of nowadays!

Just after finishing my apprenticeship I spent a year in the toolroom as 'Journeyman' where a lot of punch & die set up were machined & heat treated, the quenching media was whale oil & boy did it stink when a tray full of red hot punch's & dies was plunged in. I still have a couple of litres of 'quench oil, I've had it that long I can't remember where I got it from, it may well be some of the original whale oil from my younger days that has moved with me over the years, you know the ME adage ...'it might come in handy one day'

George.

It's a good idea to pee on your compost heap.

With all these uses of pee, I'm surprised the Victorians needed a sewage system at all.

Hardening is generally either a question of cooling down the mass of the item at a controlled (but generally rapid) rate, hence the water, brine, oil etc baths (phase diagrams etc). The process is going to be over pretty quickly as far as the metallurgy goes, surely. Or alternatively it's about surface hardness resulting from diffusion of nitrogen and/or carbon acting with high temp and time. The time and temp required for diffusion is a lot longer than for quenching and any significant depth of the surface hardness is going to require a fair while to occur.

I'd love to hear a professional metallurgist's knowledge of the matter but from my own professional experience of hardening processes, these stories sound like, well...stories. But as an engineer, I'd like to know one way or the other with reference to some form of science rather than anecdotes from the armchair, interesting though they may be.

Murray

And just to add to the many uses of pee, back in the black powder and mercuric primer days I gather it was rated by the US Cavalry as an emergency rifle barrel cleaner. I also recall reading somewhere that it was used for the early production of phosphorous, and the Romans used it for washing clothes. My grandad maintained it made rhubarb grow............

Also, thank you, gentlemen, for the reason for quenching silver steel in brine. Back in the early 1970s an old engineer told be to do it, and I've done so ever since, without knowing why.

(1) "he kept a bucket of horse pee for quenching just about everything that needed quenching"

Including his thirst no doubt.

(2) 'was fascinated by that recent BBC "Handmade" prog where Owen the blacksmith forged the knife:-

**LINK**

At 17.20 he pours some oil(?) into his quenching bath, whether topping up or floating it on the water I couldn't see.

(3) Urine, saltpetre - "Are You Taking The P*ss?"

Interesting read on the etymology here:- **LINK**

"So desperate was the need for potassium nitrate (aka saltpetre) for making gunpowder that when it was discovered that it could be made from urine King Charles I issued a proclamation that families had to collect the urine of their livestock and hand it over to ‘Saltpeter men’ who collected it daily."

But as usual.... a thread is now lacking direction and aim

Back to the original question. Out of curiosity I checked the Chronos site. I found no information as to the composition of the steel so it is impossible to say what quench is appropriate.

Out of curiosity I did a web search and found this http://silver-steel.co.uk/aboutsilversteel.php.

Silver steel is a water hardening tool steel.

That talk of whale oil takes me back ! When i was an apprentice , kept the shed behind the forge , was three red Shell 50 gallon drums . One of "20/50 ", for the vans ( used often..) one of "hoof oil ", used only on horses shod in the forge , maybe 2 pints a week .. and one of "whale oil .." for hardening .Not used very often at all...unless there was a load of breaker points to sharpen , from Southern Water .. Fair few quids worth though.. and it was "the boys job" to replenish the vans , or refill the hoof oil pot , or fetch a bucket of whale oil and do the points , £1 a point..

They lay on their sides together in a rack ,with a tap on each..and it stunk in there, and the cinder floor was soaked in old oil drips ...

Someone left the whale oil tap open ,and dripping... and it was empty next time we needed some, and the boss went absolutely mental !!

I think it may have been me ...though I was sure it " wasn't me " at the time​ !!

Back to Neil, I do it often but not in broad day light. John