I am starting to use 5160 and have found quite a difference of opinion in proper quench and draw temps. I make small blades, and want them tougher rather than harder. At this point, here's what I'm planning: profile, sperodize at 1300, triple quench at 1500, draw at 375. As a final step I've been drawing the spine with a mapp torch and getting a blue color all the way down to the tip and about 1/3 the depth of the blade (from the spine. )

If any of this is wrong for the kind of blade I want, I'd like some suggestions about what to do different.

I'll pass along my method and you can extract what you want from there....
- Forge using reducing heats as you go throught he shaping of the blade. By this I mean, start off with your highest heats, and reduce the temp you allow the blade to achieve as you go, finishing forging with dull reds.
-Normalize: I go to JUST non-magnetic and allow to cool in still air to room temp.
-Anneal: Go to non-magnetic and allow to cool in vermiculite.
-Rough grind, leaving extra material to act a a shroud during the hardening. (I go to at least 120 grit to prevent stress cracks)
-Harden in pre-heated oil. I only bring that portion of the blade to critical that I want to harden. (1/3-1/2 of the blade's width)
-Temper at 350F
-sub-zero quench (if desired)
-finish grind
I would recommend using a magnet to judge critical temp. 1500F is not enough to get everything into solution and you will likely have hard and soft spots in the blade.
On drawing the spine......I don't recommend you do this! If the blade is edge quenched correctly, you will cause more damage than you will do good. Most think that all there is to the soft back draw is to heat it with a torch until you achieve the desire tempering color. More often than not this process is rushed way beyond what it should be, and you wind up with the exterior of the blade getting a bit air hardened, while all that occurs inside is a slight crystalizing of the grain, which creates a weaker, less durable spine.
Even if you plan on using an oven with digital controls to achieve your temps, I still prefer a magnet. Your eyes can fool you on colors, gauges and readouts can be out of adjustment, but a magnet will never lie to you, and it's likely the most cost effective device that a bladesmith can have in his/her shop!

Thanks Ed, for the suggestions.

I see you mention both normalizing and annealing as steps, I assume because they reduce grain size. What convinced you to use both instead of either one or the other?

I have been using 1500 tempilaq to determine the quench temp. It was easy to check this temp against non-magnetic. I put a magnet just outside the forge door and when the tempilaq melted i touched it to the magnet. It was entirely nonmagnetic.

I understand the value of using the magnet. However, there is no way (except watching the color) to determine exactly when nonmagnetic is reached. You have to guess and then pull the steel out and check it. The actual forge temp of the steel might exceed your target temp by a considerable amount by the time you remove the steel and check for nonmagnetic. Of course experience can probably reduce this problem but it still establishes the target temp "after the fact." With the tempilaq you know plus or minus a few
degrees when the steel is at target temp. I can see, though, it's a good idea to check other tempilaq temps against nonmagnetic.

My original comments weren't entirely clear, I see. My plan was not to use both edge quench and spine draw, only the latter. Many of my blades are around 3 inches long. Do you still recommend edge quench for blades this size?

Thanks again for your thoughts.

I use both the normalizing and annealing steps. They are both different and distinct purposes. Normalizing relieves the internal stresses that build up during the shaping of the steel, sort of like you or I getting out of a car after a long trip and stretching to relieve all those cramped muscles. Annealing is a grain refining step, that when done properly sets the steel up for the heat treatment process. I didn't mention it before, but I also normalize my blades after grinding, just prior to quenching. Doing so has solved about 99% of any blade warpage during the quench. (none of us can grind exactly the same off both sides, nor use the same pressure when grinding, therefore stresses build up during the grinding process too)

I do edge quench small blades. In fact anything I do that is straight steel(s), gets the multiple edge quench treatment.

On the magnet, I do not use the forge when heat treating. All my heating during the hardening process is done with a torch. #3 tip for smaller blades, and #4 or #5 for large blades, whatever tip is used, the key is a soft flame and taking your time heating the blade to critical. Using the torch also allows me to have a magnet within inches of the blade while it's being heated, so the indications the magnet gives are usually good.