I've been planning to go to the factory in Escanaba. I've talked to the owner on the phone and found out some pretty cool stuff. 3 times a year, they close their factory and invite the public to come in and learn how to make knives. His workers pair up and take everyone from concept to finished knife. I told him I was having some trouble heat treating A-2. Sharpening my blades, I was getting a ribbon paying out from the edge rather than breaking off and forming a burr. He gave me some pointers and invited me out to the factory. The next "grind in" is at the end of February and it's followed by another in July. That might be the one for me. I was thoroughly impressed that they do that.
A cool thing to note. They buy their A-2 already heat treated and tempered. Then they grind it. I wondered if it could take the temper out of the blade. He said you make one pass, one dip in the bucket, and one pass... On and on. He said start to finish, not counting glue drying, they make a finished knife in 20 minutes. They've definitely got it down.
Bark River does none of their heat treating in house.They never have. As a matter of fact,they do very little of the cutting of the blades either.
The blades are cut by Lazer or Water Jet by an outside contractor. Sometimes the rough grind angle is cut as well. Then they are heat teated, surface ground, and THEN they show up at Bark River.
They generally like to install and haft the handles next.The very last thing they do is grind the final blade bevel, polish and sharpen the knife.
Grinding after heat treat is called "Grinding Hard". Not too many large production factories do it because of tool wear. Really if you are skilled enough to do it, you are running a coarse belt at 7,000 BFPM+ . Heat buildup is the least of your worries. If you just dip it as it warms up, you are fine.
Belt wear is the big issue especially on some of the tougher steels like CMP-3V etc. When it's hard, that stuff eats belts..
The other thing is safety. I believe Mike has his slack belt grinders set up to grind AWAY from the user. That's because even without final sharpening, once you have the Convex blade grind fully formed(even on a 36 grit belt), you then have a sharp blade that can easily kill or maim if it goes flying off the belt. Not for novices.
The reason why you may be having trouble with A2 is it is an air hardening steel that requires pretty precise temp controls to get the tempering right. It's not as forgiving as 0-1 or even 1095. Which is the reason Mike Stewart leaves Bark River's heat treat to shops that do industrial grade heat treat..
