……were you otherwise trained in the metallurgic arts before straitened circumstances forced you into a life of aimless wanderin’?

i need to sort out my favourite axe, i sharpened it on an angle grinder which was obviously a mistake as it went a bit blue and now wont keep an edge. im thinking i need to temper it but dont really know what im doing i am planning on heating it up in my woodburner and then dunking it in oil. does this sound right?

Surely smiths – a smithy is where a smith works isn’t it?

Re your axe, well it depends. Some things are case hardened which means the outside is harder than the inside so it’s less brittle. You may have ground away the hard bit.

But generally, to temper things, you first need to quench them. This means heating it up to bright red hot then dunking it in WATER not oil (oil would probably result in an explosion). This makes it brittle and hard, with lots of small crystals in it.

Then you clean it up shiny and warm it until you see colours forming. What actually happens is the heat creates a layer of oxide, the thickness of which determines the colour it appears. A rough and ready technique for home metallurgists is to judge the temper by the colour. Darker reds and blues are harder but more brittle, lighter yellows and oranges are softer.

We used to have a guide on the wall of our metalwork shop in school showing the colours for applications – IIRC things you use to hit other things were yellow or orange, so they don’t shatter.

But don’t take my word for it 🙂 I think that’s very vague.. I’ve done this for small items I’ve made and it works, but you will need to do some more reading.

http://www.iforgeiron.com/topic/19867-how-to-heat-treat-this-axe/

not oil (oil would probably result in an explosion)

Quenching in oil is pretty standard depending on the situation.

Apparently it can work according to the link I added in my edit, so yeah.. would make me nervous though!

thanks for the link. ill give it a go tonight when the burner gets roaring hot.
from what i can glean, im going to heat the whole head up till dark red, then quench the business end 3cm into warm oil then ill resharpen on a whetstone.
common sense safety aside, am i missing anything? i really like this axe, ive had it since i was 16 and dont want to **** it up (again)

(the smithies reference is a line from a film that was going round in my head as i was thinking about this)

It’s very hard to make oil explode. You need to vaporise it, mix it with air and compress it.

It’s quite hard to even make it burn.

I think that once you have quenched the end you may need to temper it by heating it back up.

http://www.bushcraftuk.com/forum/showthread.php?t=55719
http://www.neemantools.com/en/creating-process/axe-making-process
http://www.iforgeiron.com/topic/19867-how-to-heat-treat-this-axe/
http://www.ar15.com/archive/topic.html?b=6&f=4&t=355188
“Well…if you are up for some trial and error…I would say heat just the edge (1/2 to 1 inch back from edge) up with an oxy-acetylene torch to orange similar to a cooked carrot…quench in vegetable oil (do not use motor oil)…put the head after quenching into your home oven at 485 and leave it there for 3 hours. I know this sounds different than many out there have told you but I am telling you how to do it with the most simple tools. Doing all this will give you a fairly solid harder edge with a softer body which you can hammer with if you need to and not chip off (the body should be very close to spring steel hardness). When it is done, take it out of the oven HOT! and drop into a bucket or sink of cold water. This will set the hardness and it should be a range of blue black with a darker band of color at the edge. And…

Please use a drill and punch to get the wood bits out from now on!!

If you want to polish or carve or engrave this head …this is the best time to do it before you heat it up. A dremel, sanding belt, polisher, file all will work easily on this now. After you heat it….it is wayyy harder to do….”