Saltwater quench

[AtlanticDave]

I read somewhere that salt added to a water quench has less chance of cracks. It stated to add salt till you could float a potato.

Does anybody have any advice on this shade tree logic?

Cheers,
Dave

P.s. if I'm in the wrong forum, just let me know.

[Reverand]

I know that some blacksmiths use saltwater for quenching some work, but I don't know whether or not it is used for blades.
Adding salt raises the boiling point of the water. This means that the water touching the surface of the metal absorbs more heat before flashing into steam, cooling the steel faster. I don't know, but it seems to me that it might make blade steel crack or warp worse, but I may be wrong.
Most people I have watched use either a good quenching oil, or Canola oil, and preheat it to 120-degrees.
YMMV

[AtlanticDave]

Thanks for the reply,

I will have to do more homework on the subject. I wonder if the water sound be heated also?

[OLDE CUTLER]

Depends on the type of steel and what the manufacturer recommends. I have seen some info somewhere on this, will try to locate. Seems like the amount of salt per unit of water would be important.