- Joined
- Nov 24, 2003
- Messages
- 5,337
Came across 19c27 for the first time this past Friday. I past by to pay for some laser cutting of my designs in 12c27 when I was properly introduced to the new steel in RSA.
Several knife makers had made the dealer examples in (from) 4mm and I had a chance to test them (without destruction testing). The carving/cooks knife was 60RC and flexed easily, 9' long and very deep but ground to a V the whole depth and flexed considerably tip on the table the flat 45deg and my palm pushing on the centre.. Tough as nails (metaphorically). Looking at the charts the process of hardening seems to favour specialists or very well controlled manufacturing.
I am looking forward to my next batch of home jobs, I changed the order so that the larger 6' blades are going to be done in 19c27. They will be hardened by a specialist. It appears that the 19c27 is tougher than 12c27 on the same rockwell, particularly over 58RC.
The others will remain 12c27 at RC57-58 so that the non knife-nuts can sharpen them. The 19c27 is app 1/3 more carbon and is tempered upto and including 60RC after freezer treating. The cryo treated blade gets upto 61RC on tempering.
The 19c27 takes 1-2RC > than 12c27 on the same heat cycle. So to get a the same RC the 19C27 needs a higher tempering cycle.
I am wondering what the trade off will be for a knife maker / knife nut, I always find there is a penalty. What other steels is 19C27 similar to?
Several knife makers had made the dealer examples in (from) 4mm and I had a chance to test them (without destruction testing). The carving/cooks knife was 60RC and flexed easily, 9' long and very deep but ground to a V the whole depth and flexed considerably tip on the table the flat 45deg and my palm pushing on the centre.. Tough as nails (metaphorically). Looking at the charts the process of hardening seems to favour specialists or very well controlled manufacturing.
I am looking forward to my next batch of home jobs, I changed the order so that the larger 6' blades are going to be done in 19c27. They will be hardened by a specialist. It appears that the 19c27 is tougher than 12c27 on the same rockwell, particularly over 58RC.
The others will remain 12c27 at RC57-58 so that the non knife-nuts can sharpen them. The 19c27 is app 1/3 more carbon and is tempered upto and including 60RC after freezer treating. The cryo treated blade gets upto 61RC on tempering.
The 19c27 takes 1-2RC > than 12c27 on the same heat cycle. So to get a the same RC the 19C27 needs a higher tempering cycle.
I am wondering what the trade off will be for a knife maker / knife nut, I always find there is a penalty. What other steels is 19C27 similar to?
