velegski

Interesting makers mark. However if your intent is to start selling knives in the future you might consider including your name somewhere on the blade. Without a name I have hunt to find the maker since there are no official makers marks registries. Countless times I've seen someone wanting to buy a knife but they had to ask who made it because all it had was a cool mark on it

What did grain look like when you broke it. If  it mystery steel did you do any tests prior to forging.

Interesting video on Knife Steel nerds on popular quenchants including canola and their hardening effects on some of the popular carbon steels.  

Bad steel or one commercial heat treat site mentioned that improperly cleaned steel can sometime bake any organic materials into the steel. 

Another might be oxygen. The foil packet wasn't sealed good and allowed oxygen in, allowing  that area to develope scale.

I'd try a coupon and see if you get similar results. 

Then try using the heat treat numbers from other sites and see if there's a change. 

Using 220f for a tempering cycle should have resulted in 60+ hrc numbers.  

As to blotch, Steel quality is might come into play. But then test coupons will confirm.

What hardness were you shooting for and what are files giving you for reading. 

Which temp scale you using. F or C.  200? 200F isn't a common temp on tempering charts.

If I'm reading Dr. Larrins book right, grain growth is a combination the steels carbides and heat.  The higher the carbide content in given steel,  the smaller the grain size.  The higher the forging temps the larger the grain size.  The time spent at the higher forging temps allows the grain growth to increase. Too high a temperature and we cause carbon and alloy segregation.

Resetting the grain size by reheating a steel to its recommended normalizing temp, in this case 1525-1550 degrees F and soaking/holding at that temp allows the alloys and carbides to reset. Soak times for knifes are generally under 5/6 minutes.

I experiment. I use flat stock and clamp it flat for one tempering cycle. If I still have a slight bend then I use shims at one or both ends. 

Try clamping it to a piece of straight 3/16 flat stock.  use c clamps and shims to bring blade back into straight and temper for one or two cycles, 

1. Unless  you know who manufactured the cable is a mystery steel. That means you have to experiment with welding techniques and temperatures.

2. Copper melts at around 1975 degrees F. Which is probably well below your steels welding temp. Meaning it's probably going to be on the  forge  floor long before you reach the steels welding temp. 

3. Pure Nickle powder  is best played with while wearing a respirator. Improper handle can't resist in illness and lung damage.

4. Any powdered powder steel requires compression to become a solid. Just dumping it in between  strands is a waste. Hammering the cable to set the welds will probably drive most of the powder out with any flux you use. To achieve some contrast people have taken cable down to the large strands and woven nickle or nickel bearing steel wire into the strand and then reassembled the . cable bundle. Those that I've seen weren't impressive. AND as pointed out solid nickel touching 

Just my 2 cents  but what you're trying isn't a beginners task and the end product is often less than impressive. 

But, good luck!

Thank you!

Was getting bogged down on JS presentation knives so I took a minor detour for a couple days 

Now that we know you set the steel on an anvil cold enough to freeze water I'm surprised  the steel  survived the stress of that rapid a cooling change. The hot  expanded steel molecules started shrinking back to normal size in nanoseconds of hitting that freezing anvil surface. The side touching the cooler anvil had no choice but to shrink back  to size faster than the warm side, hence it warped. 

Better to clamp the tang in a vise than lay a warm or hot blade on a cooler anvil or steel table. 

Water versus oil versus commercial quench oils. Age old discussion amongst knife makers. Some advocate water, brine as their standard to good effect. Others use canola or peanut oil. And still others use commercial fast quenches.  I use parks 50 to good effect however the warpage  issue was strange. Steel I bought 1 hear ago didn't warp at quench. A small batch I got a couple months ago warped. Funny thing was someone posted an excerpt from the ASMI heat treaters guide/manual. It recommended water, however for 3/16 and under it recommended oil. Go figure! 

Boils down to what works best for you and the steels intended use.

If the 6 C oil temp is correct,  that might be part of the problem. People using Parks 50 recommend warming it to 120-140 degrees F. 

If you havent tried it, that warp might be fixed by clamping it to a thick bar with shims( like a 3 point straightening jig) and running it through a tempering cycle or two. 

Thanks for posting that. Great info!  Straight forward technique that easy to replicate 

Answer might be the string and not the prod. It might be still stretching into final length. Eye splices in particular like to stretch until everything settles into place. 

At 800 grit you should have seen the hamon boundaries. 

Try reducing your FeCl to 1:4 or 1:6 ratio.  Shorter soaks times.. times vary by makers. Times vary from several short 30 sec to 5 five minute soaks. Some use  vinegar as suggested by Latticno.

Generally I take the sanding to 1200 or 1500 grit. Then acid etching, then a light steel wool followed by Flitz polishing compound. I try to avoid additional sanding after etching I see it sometimes removing the hamon lines.

Lastly some steels develop hamons better than others. 

Sir. I'm Not that familiar with induction heat treating. Perhaps you should contact the maker of your equipment for more exacting answers. Changing your process could invalidate any guarantees your company might have or imply. 

Glad you picked up on that. I was trying to type about that flaw as you posted. I guessing but I'd bet that crack developed when you forged that curve into the blade. 

The other comments about grain size and temps are spot on. I'd suggest that you darken your forge area before doing any part of the hardening process. Doing it in daylight makes it hard to judge steel colors and you have a tendency, at least in my case to be to hot,  daylight washes out colors I see. 

Food friendly ..bees wax. Gently warm to touch blade and apply. Rub in, being careful around edge. Not ment as sarcasm, I've nicked myself more than once doing this, wipe off any excess. With moderate care it should last month or so.

Just my 2 cents. Try angle iron dies rather round dies. I find i get better welds when its compressed from 3 sides. I get fewer stray wires on exterior  and  better compression of the interior.  If hand setting try the hardy hole die shown in Sells first book. 

If this is for  knife making you might try asking on some of the knife maker  forums. While it not a common steel for knifes a Google search showed some of the Blade forums guys have used it

No help here! All my suppliers are just as short or out as everyone else. I haven't ordered from Kelly Cupples in washington state,, in a while but you might call him. No webb site available.  Phone 5099495231

Try a drive up to spokane. Pacific Steel and recycling had a bin full of RR spikes and some cut off rail road rails in approx 12-15 inch lengths. They go for scrap prices. 2 harbor freights  in town, CDA metal for clean new steel and a remenent section. 

Lewiston Clarkston has a Pacific steel and recycling as well