What happened to my blade?

[slammer187]

Well I ground my blade from 01 ground flat stock, Heat treated it, Tempered it but tempered it to blue by accident so I threw it in my home fire, Pulled it out of the ashes and ground of the scale to find this...

The blade is all pitted and uneven....Did I burn the carbon out of my blades? If so what should I do?

 

[Gill]

I think maybe your air source was too close to the steel and ate into it.

 

[bhofmann]

Hint for better photos: Get further away from it and zoom in. This improves perspective and will increase the chances your camera has to focus on the subject. Read more about that here: http://www.woodburywoodturners.org.uk/articles/ShowArticle.aspx?id=20

Actually, this is good advice for the whole forum so I'll post this as a thread on it's own for everyone to read.

 

[brancho]

No idea about HT

But Look here to improve your photography skills

 

[poddle]

I think I would start again, I am not sure what happened when you tried to repair the tempering, looks like it got quite hot there.

How long did you leave it in the fire? did you try and get it to critical or did you try to re temper it?

 

[slammer187]

I think I would start again, I am not sure what happened when you tried to repair the tempering, looks like it got quite hot there.

How long did you leave it in the fire? did you try and get it to critical or did you try to re temper it?

I tried to anneal it and left it in my home fire over night....the hottest I saw the blade get was to an orange colour!

 

[poddle]

I tried to anneal it and left it in my home fire over night....the hottest I saw the blade get was to an orange colour!

Slammer you have not annealed it, you have cooked it, hence your problem.

Start again is my advice, although you could take it to "critical temperature" and try tempering again.

It might be OK

 

[slammer187]

I'd have to quench it first, I think the blade will be fine once I clean it up on a grinder.

It's only pitting if I had done damage to the blade the tip would have melted first!
Hopefully all will go well!

 

[robin wood]

If it only went to orange you have not burnt the carbon, in fact if you did not have a blower on it there is no way you could get it to the sort of white heat at which you seriously burn the carbon out.

So you just need to start your HT again, harden, polish, temper, you can do it as many times as you like until it comes good.

 

[poddle]

Good point. Good luck Slammer.