What's a good quench?

Time to fire up the forge, warm the anvil and make some strikers out of old, small files. What's a good quench, warm canola or WD40 ?

Zam: Depends on your steel, but motor oil is usually a safe bet. Wick or one of the other serious metalsmiths will chime in here with better advice.
I need to make some fire steels my own self ...

Try one, or a test piece, with brine. If it cracks, then warm canola oil. I've never cracked file steel in brine. A tip from a meatallurgist I was talking to recently. Scale can cause cracking. High carbon steel expands when quenched, but the scale doesn't, causing stresses that can crack the steel. One 26 oz box of sea salt, 2 gallons water. I warm mine to maybe 110/120°. Brines cools faster than water and is less violent. Motor oil is too slow for a good hardness

Thanks for the replies. So it might help to heat, brush off scale, reheat then quench (if needed).

Curious, what is the carbon content of file steel?

The best quench is beer! :2 Seriuosly, transmission fluid is better than plain motor oil.

As Wick said ,you might get stress cracks with brine. What I have discovered over the years (I like my brine) is that cracks are more apt to occur when the metal is over heated. For what you intend to do it will be a good idea to have a magnet handy . When the magnet stops sticking to the metal it will be time to quench..

Twice.

Used motor oil.

Twice, non-magnetic is only 1414°. No steel will reach it's potential at that low of heat. It takes about 50° more to get a good homogenous solution of carbon and iron, even in simple steels. You will not get grain growth at 1475°, even letting it soak there. Non-magnetic is a good indicator for telling you to go one of two shades of red hotter before quench. Of course, if you get results that make you happy, what can really be said?

I agree. But with brine as the quenching agent he can quench at a lower temp and still get plenty hardness for what his intent is. My point was with my previous post to caution against over heating when using brine. For knife making the magnet trick is a sound method to follow with most carbon type steels..IMO.

Also I think we can agree on that when working with metals there are no hard fast rules to go by. Unless you have all the electronic gadgets to tell you when and what. Most of us go by our senses at a given moment and by our past experiences .
But you are correct.IMO.
Twice.

wayne1967 said:

Curious, what is the carbon content of file steel?

Click to expand...

GOOD quality files such as Nicholson are generally made from 1095 whihc is nominally .95% carbon (they may vary between .90 and 1.00%).
The older high quality files may have as much as 1.30%.

Click the link below for an article on making file knives by a metallurgist with plenty of experience with such thing

Making Knives from Files

Great article. Thanks LaBonte! :thumbsup: