pre heat treat finish requirements

Carbon steel only. Stock removal only. I shape my blades first (95% done), then heat treat. I only heat treat before shaping if making thin kitchen knives, and then my question posted does not come into play. On .125 blades, I shape the bevels and then heat treat. So, to answer Rick, no I thermal cycle AFTER stock removal, immediatley before hardening. So I take a blade that is 95% shaped, 1600 1500 1400 then 1500 soak quench, or what have you. I DO sand off the scale layers between each cycle. Takes time.....yes it does. The absense of scale allowing for more decarb. Matthew, you are right....I cannot control the decarb (actually, I think a person can.....I think there are formulas that are very acurate in determining decarb thickness for a given temp/time, but I'm not too interested in it). But leaving an edge 030 or a tad thicker, going through my normalizing procedure, I get to hard steel at around 015 or so....it has always turned out perfect. Control it? to a certain extent with time and temp. But it isn't an issue for me. My heat treat works....just trying to save some time. I'll just have to try going from my smooth cut file to 220 grit directly, and see if it isn't too much more elbow grease. I get what you guys are trying to rap into my head.....I'm asking how to save time doing "x", when I'm wasting time (in a sense) doing "y" later down the road! I'll figure it out!
 
Stuart... I can't for the life of me see where stock removing prior to thermal cycling has any advantage... I only see potential problems. I'm not trying to be a dick... but that is my namesake. It is due to the fact that we have previously discussed other similar topics about heat treat that I openly ask, WTF on this particular issue. Feel free to tell me where to go, bud.:thumbup::p

After thermal cycling, you know exactly(to a certain degree) what kind of structure you are dealing with. Any residual stresses are freed and the steel can move in the manner it needs to before you have a final shape. Prior to that, you are at the mercy of mixed structures, nonuniform grain and residual stress from the mill. What structure is easier to cold work than spheroidized martensite? You wouldn't have to compensate for movement or rely on random decarb to make sanding easier.

In my opinion, you are taking the longer, more arduous and precarious route to get to the same place. Help me to understand, why. Perhaps I am missing something.
 
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So the reasoning behind my working sequence being "out of order"? I have to point the finger at still being relatively new to this, having just acquired a decent kiln to regulate temp/time and program it in (nice), as compared to having a paint can forge. Having such a primitive forge, I limited myself to 1084 and 1080+, learning colors, how to do this, how really not to do that, and maybe a little W2 to speriment with, and never thermal cycling or normalizing. Since the addition of the programable kiln and Parks 50, it has opened doors. (Kiln is limited to 1750 max, rated 1800, so that limits me to carbon if I want to do it all in house...or in apt...I should say). I keep thinking that you're suggesting grinding hardened steel...but that isn't what you're saying, at all, I believe. You suggest to cut out the blank and clean it up, thermal cycle and then shper anneal, then grind in bevels/drill/etc, then harden. The spher structure being a great structure set up to harden as well as to work? I've heard that often....old habits dying hard and all that, you know? And the steel as received has all been very soft to work by hand with a file, so I never really saw the need to change, until now. No, Rick.....I'M the one missing it!!! I am going to change to the method you suggest, the method I believe most everyone else does it. I wasn't trying to change the world.....just now crawling from under the rock! Thank you very much Rick, Matt, and everyone else.
 
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