Chriszep
Member
Hello folks,
Id like to ask the internet what the heck is going on with my tempering colors. Ive made several knives out of 0-1 and I used to temper them in a toaster oven to around 375 and get a golden color. Recently I got myself a Rapid fire pro table top oven. Its great to use and seems much more accurate than what I was doing before with a torch and some fir brick. Here is my issue. I heat treated a new 0-1 blank, I used anti scale and the blade came out of the quench nice and hard. When I tempered it at 415 the blade came out a solid blue/purple. I thought it strange but did my two more cycles and continued on. (the blade was a test of the oven so I'm not too concerned about the hardness)
I then tried another blank, same thing, heated to 1500, soaked for a few minutes, quenched in war oil with anti scale. This time I tempered at 375, just to see what color it came out, AGAIN, blue/purple...
Now, is my kiln way off? or is it possible that a 1/8" thick blade tempering at 375 for 1 hour would come out blue?? Every chart I see online, shows blue/purple appearing around the 575 degree mark!
Any guidance on this would be very helpful. Ill attach a photo as well:
![IMG_4622.jpg IMG_4622.jpg](https://knifedogs.com/data/attachments/41/41398-a8533f54516a18a61515825a00a2eeca.jpg)
Id like to ask the internet what the heck is going on with my tempering colors. Ive made several knives out of 0-1 and I used to temper them in a toaster oven to around 375 and get a golden color. Recently I got myself a Rapid fire pro table top oven. Its great to use and seems much more accurate than what I was doing before with a torch and some fir brick. Here is my issue. I heat treated a new 0-1 blank, I used anti scale and the blade came out of the quench nice and hard. When I tempered it at 415 the blade came out a solid blue/purple. I thought it strange but did my two more cycles and continued on. (the blade was a test of the oven so I'm not too concerned about the hardness)
I then tried another blank, same thing, heated to 1500, soaked for a few minutes, quenched in war oil with anti scale. This time I tempered at 375, just to see what color it came out, AGAIN, blue/purple...
Now, is my kiln way off? or is it possible that a 1/8" thick blade tempering at 375 for 1 hour would come out blue?? Every chart I see online, shows blue/purple appearing around the 575 degree mark!
Any guidance on this would be very helpful. Ill attach a photo as well:
![IMG_4622.jpg IMG_4622.jpg](https://knifedogs.com/data/attachments/41/41398-a8533f54516a18a61515825a00a2eeca.jpg)
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