Tempering a Hook Knife.

[Scott]

Tempering a Hook Knife.

If you make the mistake of drawing to much it can be corrected. The blade would have to be re-hardened so the last step would have to be repeated. You don’t want to do this because there would be a good chance of damaging your blade. I think the main points are patients and easy does it. Practice first with the second piece. Clean the tang and the back of the blade to show the steels brightness Temper in two stages. First, place your piece, tip down, making sure you have a clear view of the brightness of he steel, temper the whole blade and tang the same; a straw colour in your oven at 460F for 10 minutes if your ovens thermometer is accurate. It is best if your unsure to check the colour by very quickly cracking open your oven door and looking at the blade colour every 5 minutes or so (do this with goggles on or you will lose your eye lashes). When it reaches a staw colour, douse it in a litre of room temperature water. Though lumber mill band saw steel has tensile strength built into it, the tip of the hook blade is vulnerable to breaking and, of course, it should still be hard enough to keep a sharp point and edge. Taking a touch more hardness out of the tip and blending down into the blade a couple of cm. can give just enough forgiveness to avoid losing the hook tip. It is very easy to burn the tip so be careful. One does not want the tip beyond a dark straw. To strengthen the hook tip go back with a propane torch to take more hardness out of the tip. This technique is called differentially tempering. By passing 10cm (5") or so away from the tip down the hook 3 or 4 cm, keeping your distance and then cicling around to the tip you’ll create a motion at a steady pace watching intently at the colour. The minute it begins to turn, quckly douse it into your water. It is always advisable to take some hardness away from the tang to assure the blade won’t snap at the handle. This can be done on a stove element. On maximum, place 3/4 of your tang onto the grill. As the colour goes into blue hold your blade with an oven mit and douse the tang into your water. My tempering process is tricky. It took a lot of time, experimenting and effort to perfect but the temper in our hook knives will allow one to carve hardwoods like crabapple wood, maple, oak and my favorite cherry without losing the knives’ razor edge or snapping or permanently bending the fine point off the hook which every commercially bought hook, bent and crooked knife will with a little bit of torque. This process allows us to put longer handles on our knives for the greater control and power of two hands especially when carving larger projects. One can scribe deeper lines without the threat of losing the knife’s edge or snapping the point

http://www.caribooblades.com

[Hi_Ho_Sliver]

those are great looking knives , would love to have one but can't justify, doubt I would be using it enough.......I assume it is razor sharp...

[whitecree]

I've been waiting all summer for this tempering info. Great to have!


Do you also make a more deeply hooked knife? That is, one that is almost horseshoe shaped?