Measure blade temperature while using torch for heat treat

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I have some 1095 I plan on heat treating with my oxy-acetylene torch, and I would like to be as accurate as possible, on a limited budget.

What is the best way to measure the temperature of the blade during heating? I know they say to "heat to non-magnetic" and because 1095, to leave it there for a minute, but I was hoping to have some tighter control. I have a thermocouple readout; should I get a high temp probe and place it next to the blade?

Would I be better served just using the torch for fabrication of a kiln/furnace with a propane burner or something?

Any advice or tips is appreciated!
 
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1095+ torch heating + 'tighter control' = Nearly impossible.

1095 is not the best steel to heat with a torch. You aren't going to have very precise temperature control unless you REALLY know what you're doing. The guys that heat treat with a torch with success have lots of practice and a good eye for judging temps by color.

Even if you have that part down, 1095 needs a bit of an extended soak and excellent temperature control. If you don't have that, I wouldn't even attempt it. Even if you think, 'That's all I have and it's just for me to get practice'....I think you're wasting your time. IMO, you'd be further ahead to just get some 1084 or 1075 from Aldo and save the 1095 for when you have more accurate equipment.
 
A much better idea than making an oven in the early days of knifemaking would be to send them out for HT. This will assure a perfectly hardened blade with no warps.

HT with an O/A torch is a learned skill. It can be done, but even for the pros, it is hit and miss. Even the best torch HT will not likely be as good as a proper oven HT.
 
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If you put a little thermocouple in a flame next to a comparatively massive knife blade it's going to read much hotter, and possibly melt, because it's going to reach the temperature of the flame. It would need to be attached to, or embedded in, the blade to tell you the temperature of the blade in a flame. And then it will tell you the temp of that spot.

edit to add:
Some people can do this with a torch and get good results, but I think it must take a lot of experience and a good eye. And I'm not sure how repeatable it would be from blade to blade or even along the length of an edge.
 
I HT almost exclusively with a torch (used to use O/A, went over to O/P because acetylene is obscenely expensive) and it takes a long, long time to get good at it. If it's done right, it's right (use the right steels and be careful) but the first long while there are going to be some lemons.
 
I did this on my first blade, not the best way but it satisfied my horn-ball to get it done.



Long piece of steel, about 3/4" thick and 1 1/2" wide 2 feetish long

Held in a vise at the end with a couple of feet stick out.


I torched the steel with the knife on top of it.
That way the knife got a more gentle even heat

Judged temp by working in the dark and watching colour and decalascence and http://www.tempil.com/



It wasn't fast

By torch I mean a real oxy fuel torch and a rosebud tip; not those little handheld bottles.
 
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