tripping lever - sten

[Flying10uk]

When you say heat harden, tankhunter, I assume that you mean harden and temper rather than case harden which is also a type of heat hardening process, it could be argued?

[tankhunter]

I hardened & Tempered them F10. Case hardening would have had a similar result for a live gun. But I don't have any case hardening compound in my Workshop. So........

[browningautorifle]

I tried Kasenite and had limited results. I'd rather use oil myself, you end up with a black finish too...don't know how hard it gets though, didn't Rockwell it after. My problem in all of this is how hot is hot? How long at cherry red...? I guess that takes experience.

[Vincent]

If you are through hardening, you can suspend the part with a magnet over the oil bucket. When the part is hot enough it will become non-magnetic and fall into the oil.

[Flying10uk]

It partly depends on the grade of tool steel on how hot you need to get it before quenching in oil. If I was going to make the tripping levers out of a tool steel and then harden and temper it, just basic ground flat stock (Gauge Plate) or 01 grade tool steel would probably suffice. This is a fairly basic standard tool steel and for this steel if heating in an oven a temperature of around 815 degrees centigrade would be about right. For the tripping lever you wouldn't need to hold the temperature long before dunking in oil because it's relatively thin; in an oven holding for around 15 to 20 mins should be long enough. If I was hardening the tripping lever in a flame the secret is to slowly bring it up to temperature by gradually increasing the size of the flame. You need to have the metal a little hotter than cherry red, more of a orangery yellow colour and the colour needs to be uniform across the metal. For a thin item like the tripping lever once the metal is up to this colour it would only need holding in the flame for a few minutes before dunking in oil.

[browningautorifle]

If you are through hardening, you can suspend the part with a magnet over the oil bucket. When the part is hot enough it will become non-magnetic and fall into the oil.

Perfect. That's easy to remember.