Did i over temper

[Jpgied]

The blade is ¼" 1084. I had hand sanded one side and etched with FeCl to see if i got any temper line. That's when i realized i didn't do a second temper and threw it in the oven for an hour at ~400. Now it looks like this. Tell me it could be a chemical reaction or something

https://drive.google.com/file/d/13UvNprxi0tTOSAICAc5sN5HvnVJ8aQjz/view?usp=drivesdk

https://drive.google.com/file/d/12l9GO1S5RhOdDeOvmcFzAAXoOmRhl7MH/view?usp=drivesdk

 

[kuraki]

We can't tell you the hardness of your blade by looking at it. Color is extremely unreliable at indicating temper temperature and can vary based on surface oil or other substances. If you've monitored your oven temperatures and know 400F is 400F, then likely it's fine.

I'm inclined to believe the splotchy blue colors are a result of substances not fully cleaned from the surface due to how they vary in consistency, but I don't know if "threw it in the oven" meant directly over the element, if the oven was allowed to stabilize at the set temperature, etc.

 

[Kevin McGovern]

If you are using a toaster or kitchen oven and aren't using an accurate thermometer (the ones that are built in are NOT accurate) then I really couldn't say.

 

[Jpgied]

I realize I'm probably asking something impossible to answer. It was placed in a cold toaster oven uncovered. Usually gets pieces out of it a straw color, but normally they're wrapped and the oven preheated. Thanks for the input, i might be requenching

 

[Natlek]

I realize I'm probably asking something impossible to answer. It was placed in a cold toaster oven uncovered. Usually gets pieces out of it a straw color, but normally they're wrapped and the oven preheated. Thanks for the input, i might be requenching

You can clean , degrease blade and temper again .....To see why you get that color .I always on any carbon steel get gold color on 400

 

[Jpgied]

You can clean , degrease blade and temper again .....To see why you get that color .I always on any carbon steel get gold color on 400

I have a few cut off pieces i could use for this, thanks for the tip

 

[JTknives]

Did you say you put the blade in a cold oven and it was uncovered? If so then yes I would say you fryed the blade. As the oven is coming up to temp it’s pumping out a lot more heat then is needed to hold 400°. The blade would soak up all this heat and quickly shoot past 400°

 

[Jpgied]

Did you say you put the blade in a cold oven and it was uncovered? If so then yes I would say you fryed the blade. As the oven is coming up to temp it’s pumping out a lot more heat then is needed to hold 400°. The blade would soak up all this heat and quickly shoot past 400°

Thanks a lot. I'm definitely reclaying and starting over.

 

[Stacy E. Apelt - Bladesmith]

Sometimes I get all sort of peacock colors in tempering. It is from oils and such on the blade surface.

That said, placing a blade in a cold toaster oven is a pretty bad idea. I would do a brass rod test on the edge. If it tests OK, no problem. If it is too soft, then re-do the HT.

 

[Jpgied]

Sometimes I get all sort of peacock colors in tempering. It is from oils and such on the blade surface.

That said, placing a blade in a cold toaster oven is a pretty bad idea. I would do a brass rod test on the edge. If it tests OK, no problem. If it is too soft, then re-do the HT.

10-4. And lastly, if i redo the HT, is there any extra steps i need to take before trying to force a temper line with clay again? Or does it just get reset when it hits critical?

 

[Stacy E. Apelt - Bladesmith]

If you redo the HT, just clay it and bring back to austenitization temp. The existing martensite and pearlite will all convert to austenite around 1350F.