? about Saltbath H.T.

[mtnsct]

First I want to thank all the contributers to the forum for the incredible wealth of information! I started making knives a few months ago and you all have helped immensely with my education. I hope I can repay the debt with future contributions.

My first question has to do with H.T. in salts. After reading through most of Mr. Cashens' website I gather you can stick a room temp. blade directly into the HT salts and start the austinitizing process. Yes? Or are you pre-heating the blade before immersion in the salts? If no pre-heating, couldn't I do the same thing in my EvenHeat kiln? Or do the salts change the senario?

From the heat treating info. I have gleaned from Crucible, Timpkin etc. the procedure was explained as a slow ramp up to the aus. temp. Some as slow as 400 deg. per hour to prevent stress on the steel. Does this only apply to thicker sections of steel?

Rod Garcia

 

[mete]

The ramping is mostly for thicker sections.

 

[JCaswell]

I have never had trouble --- never cracked a blade (pre-ground or not) in salt. Very minimal warping--usually none at all.
I usually go straight into salt full temp and marquench. (This would be carbon steel damascus.)

 

[mtnsct]

Thanks for the answers guys. I won't have to be so anal about the steel cracking or the preheat cycles.

Is this also the case with most tool steels like D2, A2, 3V, etc. i.e. thin cross sections heated up to aus. temp quickly?

 

[Plain ol Bill]

A blade should be warmed to the point that it will not form condensation as you put it into the salts. A single drop of water into hot salts will cause it to "pop" hot salts out. Not a good thing. Don't ask how I learned that - OK.