Quote:
Originally Posted by RantNRave
Yup, truer words were never spoken: "confusing to you" 
You say heat the oven to 1475 then put the blade in for 8 to 10 minutes. I know this may sound stupid, but I have to ask. Again, I'm a literal person, so forgive what may be a stupid question. By this, do you mean: heat the over to 1475, put the blade in and let the over heat back to 1475 and THEN time 8 to 10 minutes?... |
Oven is at 1475F, blade is introduced, oven drops ten to twenty degrees in temperature, when the rebound is done and the blade is at the original set temperature the timing begins.
There may be more time for rebound in an oven, but in my salts, due to the conductivity, as soon as the thermocouple reads the original set temperature, the blade is at temp and the soak begins. I have even programmed it into controllers before that they will read when the set temp is obtained and then the timer is triggered and an alarm goes off when it is time to quench. For steel in average spheroidized condition an 8 to 10 minute soak is enough for maximum hardness. The differences in proper solution can be quite noticeable in as quenched hardness but also in tempering temperatures.
One of the reason I am always very hesitant to give numbers for HRC to tempering temperature is that it is a moving target. Depending on your amount of proper solution the tempering temperatures can varying as much as 50 to 75 degrees for the same HRC number. 1095 with no soak, may reach 59-60 HRC with tempering around 400F-425F, but with proper solution you will be pushing it well beyond 450F for the same hardness.