Weird Sharpening Experience...Bad/Damaged Temper?

[garry3]

Pretty much all vintage axes can be sharpened with a file - with few exceptions. The problem arises from the oxidation layer that forms on old axes (under the rust). That surface layer is harder than the underlying steel.

Work through the oxidation layer in one small area. Then work out from there with the file, raising the oxidation layer from below. It's much easier this way and you won't dull your file so easily. When your file clogs up, clean it with a file card.

I always thought that hard layer was work hardened. Harder just from being pounded. Oxidation causes this? Is this just on rusted heads?

 

[G-pig]

I always thought that hard layer was work hardened. Harder just from being pounded. Oxidation causes this? Is this just on rusted heads?

I think they might confound each other. That, along with the simple fact that an axe that has been honed and used a lot between filings is worn smooth and the file takes a bit of time to get it's own kerf going.

 

[garry3]

I think they might confound each other. That, along with the simple fact that an axe that has been honed and used a lot between filings is worn smooth and the file takes a bit of time to get it's own kerf going.

So both conditions exist? Sounds reasonable. And compounder by a burnished work surface(or polished). We all know that outer layer is for sure harder than whats under it.

Thanks G-pig

 

[Chris Montgomery]

Work hardening happens on many good steels. That can also cause the deeper gouges with a file. When you apply more pressure the file responds by taking more steel from the area being worked. As it does the material removed can harder and gall. It's also hard on a good file. I have had it happen on 5160 steel several times.

Chris