Saturday, May 11, 2019

FRIDAY AT THE FORGE

Well now, what a very interesting and almost scary day of heat treating steel. After watching some You Tube videos and one in particular from The National Research Council on tempering and heat treating steel, I felt ready to take the adventure, knowing all that could go wrong, and writing out a step by step procedure, and rehearsing the procedure, then making sure I was following every step, we began. 

Step 1. The Quench: Clean the steel so that it is free of slag, dirt & oil. Prepare the forge, and the quenching container to be in close proximity of each other and heat the Quenching Oil to 130/140 Degrees Fahrenheit, because hot oil has less viscosity and therefore cools quicker than cold oil.

Step 2. Heat the steel to be quenched to between 1450 & 1500 Degrees Fahrenheit (Critical Temperature or the state of nonmagnetic) evenly, so that the entire piece reaches Critical Temperature at the same time. Then quench it in the hot oil being very careful not to cause a flash flare up of the oil, move the steel slowly up and down in the oil to reduce air bubbles until it reaches between 400 /600 Degrees Fahrenheit. 

Step 3. At this point we removed the steel from the quench and placed it between two pieces of angle iron positioned in the vise, and clamped the steel between the angle iron and tighten the vise, this procedure eliminates warping and twisting of the steel and allows it to cool to the touch.

Step 4. When the steel was cooled we removed it from the vise and closely checked it for straightness, hardness, cracks, & cold shuts, etc. Then clean off all the slag created by from the forge, from it and shine it, install the brass guards, and it is ready to temper. 

Step 5. Tempering, this took place when we placed the steel in a preheated oven at 500 Degrees Fahrenheit for a period of one hour and the cooled while remaining in the oven. This results in a beautiful purple colour  with a narrow strip of blue on the edge. This is exactly what we want and where this part of the story ends.  

From here we must clean it, shine it, sharpen it and install the handle, which will take place next week.

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