Just working on my #4 and this one I'm making for a friend of mine but it calls for 1/4 thick blade thats 7 inches long I'm using Aldo's 1084fg and was wondering should I be able to heat this ok in coal fire and will I be able to temper it in a regular cooking oven. I thought I might have read somewhere that larger pieces like this need higher tep. 500-600f to temper. Ty in advance
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Can 1/4 1084 be HT in a primitive fashion
- Thread starter Utican
- Start date
Tempering temperature has nothing to do with he mass of the piece. If you've got a greater mass you may need a longer time at your tempering temperature to make sure you get the whole piece up to heat, but don't go bumping up your temps or you;l just be making the blade softer than you want.
If you're heating in a coal fire, get a good, long fire going and put a piece of pipe in the fire to act as a muffle and even the heat out. Stack your coal all around the pipe so you get an even heat from all sides. Keep a very low air blast going to heat things slowly. Start heating the blade tang-end first since the majority of the mass of the blade is in the ricasso area. If you heat the ricasso first, you'll run less of a risk of overheating the tip as you wait for the ricasso to come up to heat. If you work in a somewhat darkened room you'll have a better chance of seeing decalesence/recalesence to know when you're at the proper temperature for normalizing and quenching. When you can pull the blade out of the muffle tube and see slight "shadows" running through the steel as it cools slightly, you know you've got your carbon in solution. Don't go more than a hair higher in temp than this or you'll start grain growth you don't want. Normalize from this temperature twice. When you're going for your quench, get up to your austenizing temp again, pull the blade out to check for the shadows of recalesence, and go back into the fire for a few seconds to bring it back to just above that temp. Then quickly, without hesitating, go straight down into your quenchant and agitate up and down quickly as it quenches. Once the violent portion of the quench stops, pull it out and check while it's still hot for straighteness. Use the time before you hit 400F to straighten with a stick of hands in heavy welding gloves. Then back into the oil to cool a bit more.
Start your temper at 375F in your oven for an hour. Repeat your temper a second time and check for chipping with the brass rod test. If you've got no chipping of the edge, you're good. If it chips out slightly, re-temper at 400F for an hour and try again.
Hope that helps! I know it can be daunting to come here and ask about not using engineered quenchants and kilns because so many of us are shooting for the maximum from every blade. I can tell you from experience that you can make a good, serviceable blade in a coal forge. I've done it many times. Are you extracting every ounce of performance? Probably not. If you do it all right, and pay attention to the steel though you can get pretty close.
-d
If you're heating in a coal fire, get a good, long fire going and put a piece of pipe in the fire to act as a muffle and even the heat out. Stack your coal all around the pipe so you get an even heat from all sides. Keep a very low air blast going to heat things slowly. Start heating the blade tang-end first since the majority of the mass of the blade is in the ricasso area. If you heat the ricasso first, you'll run less of a risk of overheating the tip as you wait for the ricasso to come up to heat. If you work in a somewhat darkened room you'll have a better chance of seeing decalesence/recalesence to know when you're at the proper temperature for normalizing and quenching. When you can pull the blade out of the muffle tube and see slight "shadows" running through the steel as it cools slightly, you know you've got your carbon in solution. Don't go more than a hair higher in temp than this or you'll start grain growth you don't want. Normalize from this temperature twice. When you're going for your quench, get up to your austenizing temp again, pull the blade out to check for the shadows of recalesence, and go back into the fire for a few seconds to bring it back to just above that temp. Then quickly, without hesitating, go straight down into your quenchant and agitate up and down quickly as it quenches. Once the violent portion of the quench stops, pull it out and check while it's still hot for straighteness. Use the time before you hit 400F to straighten with a stick of hands in heavy welding gloves. Then back into the oil to cool a bit more.
Start your temper at 375F in your oven for an hour. Repeat your temper a second time and check for chipping with the brass rod test. If you've got no chipping of the edge, you're good. If it chips out slightly, re-temper at 400F for an hour and try again.
Hope that helps! I know it can be daunting to come here and ask about not using engineered quenchants and kilns because so many of us are shooting for the maximum from every blade. I can tell you from experience that you can make a good, serviceable blade in a coal forge. I've done it many times. Are you extracting every ounce of performance? Probably not. If you do it all right, and pay attention to the steel though you can get pretty close.
-d
- Joined
- Feb 17, 2007
- Messages
- 3,375
The pipe acts to keep the temperature even everywhere inside it. Just using the coal or a torch it is hard to get the blade heated evenly.