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Old 07-23-2004, 05:32 AM
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Crex Crex is offline
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Location: Acworth, GA and/or Hanging Dog, NC
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Mark,
Glad to be able to help. Let's face it, unless you get a lab analysis of the steel you don't really know exactly what type of steel you have. The way you described the break and hardness, I'm not sold on it being 41xx series. If it's still tough after annealing then your annealing process is not right for that particular steel. Many of the alloy steels require a multi-stage annealing to get them to "dead soft". A lot of alloy steel aslo "air hardens" to some extent so just bringing up to critical temp is not all there is to the annealing process. Best results come from very slow cooling down from critical. Most simple Hi-carbs respond well to over night in a bucket of vermiculite that has been preheated with a chunk of hot scrap steel. Bigger the mass of the scrap the slower the cooling process.

Critical temp varies from steel to steel. The magnet test has always proven satisfactory for me. I do my HT in my forge and go by mag and color to determine the critical temp, so I don't have a set temp # to give you. Also I do very little grinding other than to clean up profiles. I do 85 to 90 percent of my shaping and bevels with hammers. Can't say that my hammer has noticed any problem with the normalized steel hardness .

On the normalizing, I usually take the unknown steel to critical temp (non-mag) and then take out and let cool in still air. If you are doing this in an airconditioned shop or with a fan on, you need to turn these off so that the air is still. I handle everything by the tang and move slow and deliberatly, clamping the end of the tang in a nearby vise and let cool to touch before doing it again. If this doesn't work for this particular steel, suggest slipping it into that bucket of vermiculite for a couple of hours then pull out and air cool to touch.

How much will it cost you to have the blades laser cut? You might come out better in the long haul to buy a good "port-a-band" band saw and a supply of bi-metal blades. This will cut up any masonary blade quite well (ifyou avoid the diamond matrix) and you have a very versitile and usefull tool for other projects and needs. I find mine quite indespensible. A little planning and attention to cutting and you should be able to cut your blanks down to pretty close to profile with very little effort.

Carpe ferrum!


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