HT timing...

Ron Raducanu

Ron Raducanu

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Feb 10, 2021
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I've never heat treated anything before. I realize that the times are mostly estimates.

The idea for this thread is to get an idea of how long it will take from beginning to end to HT my little knife. Watching YTs about this doesn't really give me an idea of the time involved.

I'm building one of those little insulated fire brick forges, and have one ts4000 torch. The steel is 1084 and about 6-8 inches long and is 1/8 inch thick. It's the little beginner knife in Red Beard Ops' YT.

I know that the tempering cycle is 2 rounds for 2 hours each at about 400F. So that's a little over 4 hours, with time in between for cooling.

I've also read that with my set up, it takes about 10 minutes to heat the forge to temp.

So how long does it get the steel to normalize using this set up (about)? Two normalizing cycles should take about how long (with cooling in between)?

I have a quenching set up with a gallon of Canola Oil in a paint can. I have a little chafe to heat it up and a temp gauge to make sure the oil doesn't get too hot. Once normalized is the heat up time for the steel about the same time as it took during the normalizing cycle?

I'm asking all this because I don't get a lot of continuous free time, so I'm trying to plan my day around HTing this little knife. I know that when I'm normalizing and for the quenching, I can't just leave to do something else while this is going on. Once it's in the oven, I can do some stuff in between.

Thanks for any input!
 
Carbon steel HT using a forge doesn't take long.
Make sure your forge has run for a while to make the inside chamber "soaked" with the heat.
Heat the knife, keeping it moving and turning, and checking it with a magnet as it gets red until the magnet stops sticking. That is around 1350-1400F. Heat a shade of red hotter to get to 1475-1500F. Try to keep the tip and edge from overheating, and when the blade is ready, pull out and quench in 130F canola oil (at least one gallon for a small knife).
Keep in the oil for at least 10 seconds, and pull out to check for warpage. You have about 10 seconds to straighten it before it gets too brittle to bend(400F).
Cool to room temperature and then temper twice for one hour (two hours for high alloy and stainless steels).
After the first temper, cool in water (running tap is fine) and put in for the second temper cycle.

All combined, it should take 3 hours.
 
Ron Raducanu said:
Two normalizing cycles should take about how long (with cooling in between)?
Click to expand...
Depending on the thickness of the blade, I'll estimate 30 min. I do mostly kitchen knives and my blades are typically ~0.090" at this step and they heat up and cool rather quickly. A thicker blade will take longer.
 
Is the blade forged or stock removal?
If stock removal, no need to normalize.
If forged, it should have been normalized at the last forging heat. If you didn't do it then, yes normalize the blade. That should take 10 minutes tops.
 
JT is correct. Some sellers use steel that is very spheroidized. It needs normalization to harden properly. I haven't had issues with NJSB steel, but JT and others have seen low hardness results unless it is fully normalized.
 
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