That's my thoughts as well but I wanted to make sure,,,, Also was wondering how much faith I can put in the testing blocks that came with my import Rockwell Tester. The tester is consistently 1.5 to 2 points lower on all 3 of the C scale blocks. My thoughts are to order a quality set of USA made testing blocks to check it with. Any thoughts on this anyone?
Thanks,
Jeff
I just got this machine about 3 days ago. Until then I was just going by the normal recommended receipts found for CM154. Ramp to 1400 for 10 minutes - ramp to 1950 for 35 minute soak time - Then plate quench while using air between the plates - sub zero freeze - and then 2 tempers at 400 for 2 hrs - I have 5 knives that Im checking and all five are a consistent 59.5 to 60.3. But yet all 3 test blocks are consistently 1.5 to 2 points low. So my concern is that all 5 knives are 1.5 to 2 points higher. Which in turn makes me worry about the cutting edge chipping while in use... Now that I look back.. "That's a hole lot of worrying" :15: :biggrin:
I just got this machine about 3 days ago. Until then I was just going by the normal recommended receipts found for CM154. Ramp to 1400 for 10 minutes - ramp to 1950 for 35 minute soak time - Then plate quench while using air between the plates - sub zero freeze - and then 2 tempers at 400 for 2 hrs - I have 5 knives that Im checking and all five are a consistent 59.5 to 60.3. But yet all 3 test blocks are consistently 1.5 to 2 points low. So my concern is that all 5 knives are 1.5 to 2 points higher. Which in turn makes me worry about the cutting edge chipping while in use... Now that I look back.. "That's a hole lot of worrying" :15: :biggrin:
I just got this machine about 3 days ago. Until then I was just going by the normal recommended receipts found for CM154. Ramp to 1400 for 10 minutes - ramp to 1950 for 35 minute soak time - Then plate quench while using air between the plates - sub zero freeze - and then 2 tempers at 400 for 2 hrs - I have 5 knives that Im checking and all five are a consistent 59.5 to 60.3. But yet all 3 test blocks are consistently 1.5 to 2 points low. So my concern is that all 5 knives are 1.5 to 2 points higher. Which in turn makes me worry about the cutting edge chipping while in use... Now that I look back.. "That's a hole lot of worrying" :15: :biggrin:
You should come out around 59HRC to 61HRC with that recipe.
Your blocks will have some hand scratchy engraving telling you what the hardness is. What do you get when you test compared to how it is marked?