While I was hunting to day I noticed the abundance of black walnut trees on the property and I was wondering if quenching in walnut oil gathered from squished hulls would do much. That stuff dosn't come off of anything and I was wondering if it would leave kind of a reverse hamon on the blade from an edge quench. anyone ever tried this?

Would take a bunch of walnut hulls to get enough oil for quenching, I think. And you would have to catch the hulls at the right time as the dry pretty quick thus yeilding less oil. But, only one way to find out! Be sure to post your results on this thread too! :)

The black liquid that comes from the decaying husks isn't walnut oil; it's a water-soluble solution of tannins and I dunno what else. I predict you'd crack a lot of blades trying to quench in it. Walnut oil comes from the meat of the walnut, and it's oily and only a little darker colored than typical vegetable oil. (It's also expensive to buy and a real chore to make, and I'd guess it would make a very poor quenchant in a number of ways -- two being that it oxidizes readily and it's especially sensitive to heat.)

You can color steel (or maybe just rusty steel?) by boiling it in a strong tannin solution like a soup made from walnut husks. That's an old trapper's trick for dyeing steel traps. You might want to experiment with that. But I'd do it as a separate step after quenching.

Edited October 23, 200916 yr by MattBower

MattBower: Would coloring the metal in this manner act as a rust preventative? Would the metal retain the qualities of a polished surface, but be darkened?

I too have several black walnut trees on my property, and happily do *not* have a bumper crop this year!

Phil

Iron tannates do protect from rust a bit but won't provide much protection under severe duty conditions

Thomas is correct. I have used this method on steel traps and it does create a sort of light blued look that is significantly more rust resistant than bare metal but it is not going to hold off all rust forever. Some tree barks do the same thing.

I like walnut oil as a finish for things that will be used for food like cutting boards and carved wooden spoons. It will dry and so you can build up two to three coats for fair durability. It is a slow drier though and I find that lots of heat (like direct sun or car dash exposure) is useful to accelerate the drying time between coats. For this type of use it is quite reasonably priced... a pint bottle costs me about $5 to $7 and will finish dozens of spoons and bowls. Total edibility is the big advantage for this type of use.