Thread: The greatest thing this hobby has given me

I'll be interested to hear from others. Thanks Andre.

That grain structure screams bad heat treatment and normalizing.

After seeing that, forget icing the blade it needs to be re heat treated anyway. Weld the handle on however you want, clean up the weld, and do a full heat treatment on it. Brazzing with silver is probably the best option for appearance, brass would work as well - especially if you came back and plated the whole tang.

If you want to do a fixed wood handle on it, just grind back the broken off piece until square and weld about a foot of rectangular bar to it. (The extra long bar makes it easier to weld and clean up). Then cut the bar to length for the handle, drill two or more holes to hold the bar to the handle, and heat treat the whole thing.

Chris do you think that grain structure would support an edge that thin? I wonder if it didnt just get partially submerged during quench... therefore it broke near the quench line. Maybe that section stayed hot for too long leading to grain growth? Just speculating here

When you bring it up to weld temperature the grain structure will change. After welding it, you will need to heat treat it and the grain will change again - hopefully to small, fine grain. Then you normalize it.

To me it looks like it was haphazardly dropped into the quench and the stamped side cooled quicker than the nonstamped.

I am not sure the edge will survive a quench straight... but that might explain the warp

Originally Posted by puketui41

Here are pictures of the fracture...(pix clipped to save bandwidth) Now that I look at the blown up photos it looks like inclusions in the top right of the first photo

I don't see any inclusions, but that is some largish-grainy stuff. There are many more fracture prone boundaries in large crystals than in smaller. Likely, it was hard enough according to the shop practice of the day and put into the pile of razors to be finished.

The largish crystals are the source of warping in some steels. Refining the size of the crystals can reduce the warping to a great degree. In the era this was manufactured, thermal cycling was an unknown.

As to the discussion about welding this tang back together...it can be done by a good welder, perhaps a good TIG operator, but yes, some sort of heat transfer barrier is absolutely necessary if you intend to not affect the heat treatment at the edge. I would be concerned about the heat affected zones where more grain growth could occur during the welding. You might fix the first weld and leave two more spots where another fracture could occur.

Or, fix the tang, then redo the heat treatment of the whole blade which would even out the concerns about localized zones of different heat histories in the whole blade/tang. But, that requires a very good heat treater and you are still likely to wind up with a potato chip edge unless you are really lucky. Salvaging that would lose some x/8 dimension.

Thanks again for the photos.

Wow the steel o1 i experimented with with grain that size didnt even keep a 15deg per side edge... satisfactorily... it was on a kitchen knife... so the demands are a bit harder...