01-07-2018, 02:37 AM
Steve,
Very thoughtful post.
Irwin (formerly Marples) 3/4” Blue Chip chisels are my go to learning tools with the Tormek. They are bench chisel length, have properly ground non radiused backs, and are inexpensive. I have around a dozen, all 3/4”. Having several allows me to compare different stages of grinding and different grinding wheels side by side.
I did some testing of 80 and 180 grit CBN wheels with my Tormek. As part of the testing, I ground chisels (standard 25° bevel) with both CBN wheels. I am recalling the BESS numbers from memory. The 80 grit wheel used alone produced a reading just under 500. The 180 grit wheel produced a reading of around 400. Both edges looked gnarly, or in knife people terms, had very adequate toothiness.
I wanted to see how much I could lower the BESS readings by going directly to the leather honing wheel charged with Tormek's standard PA-70 honing compound. After around a minute, I was surprised with BESS readings around 130. Not bad for a cheap and dirty two step. The bevels cleaned up considerably with the long honing time, but still would not win any smooth polish awards.
As a control, I also sharpened an identical using the traditional three step method with the Tormek SG-250 aluminum oxide wheel. Again, relying on memory (not terribly scientific at my age), this more careful method yielded a BESS reading of 100. The CBN wheels win hands down for reshaping turning tools. I much prefer the traditional three step Tormek method for sharpening chisels and plane irons.
I know your combination method of using the Tormek for grinding and stones for honing is popular and effective. I understand the logic behind it. Please do not be offended by my next questions. is your preference based on side by side comparison after becoming very proficient with the stone grader and leather honing wheel? Or are you basing your preference on the higher grit numbers of the water stones (8000 to 30,000 compared with 6000 for the honing compound)?
I realize that the stone grader can seem tedious and the leather honing wheel problematic. They were for me for several years until I made an intense effort to understand them. (another plus for having some sharpening/practicing chisels) I am not defending Tormek; I am just curious. I am well aware that the answer may be "It depends", factoring in the application and species of wood.
Ken
Very thoughtful post.
Irwin (formerly Marples) 3/4” Blue Chip chisels are my go to learning tools with the Tormek. They are bench chisel length, have properly ground non radiused backs, and are inexpensive. I have around a dozen, all 3/4”. Having several allows me to compare different stages of grinding and different grinding wheels side by side.
I did some testing of 80 and 180 grit CBN wheels with my Tormek. As part of the testing, I ground chisels (standard 25° bevel) with both CBN wheels. I am recalling the BESS numbers from memory. The 80 grit wheel used alone produced a reading just under 500. The 180 grit wheel produced a reading of around 400. Both edges looked gnarly, or in knife people terms, had very adequate toothiness.
I wanted to see how much I could lower the BESS readings by going directly to the leather honing wheel charged with Tormek's standard PA-70 honing compound. After around a minute, I was surprised with BESS readings around 130. Not bad for a cheap and dirty two step. The bevels cleaned up considerably with the long honing time, but still would not win any smooth polish awards.
As a control, I also sharpened an identical using the traditional three step method with the Tormek SG-250 aluminum oxide wheel. Again, relying on memory (not terribly scientific at my age), this more careful method yielded a BESS reading of 100. The CBN wheels win hands down for reshaping turning tools. I much prefer the traditional three step Tormek method for sharpening chisels and plane irons.
I know your combination method of using the Tormek for grinding and stones for honing is popular and effective. I understand the logic behind it. Please do not be offended by my next questions. is your preference based on side by side comparison after becoming very proficient with the stone grader and leather honing wheel? Or are you basing your preference on the higher grit numbers of the water stones (8000 to 30,000 compared with 6000 for the honing compound)?
I realize that the stone grader can seem tedious and the leather honing wheel problematic. They were for me for several years until I made an intense effort to understand them. (another plus for having some sharpening/practicing chisels) I am not defending Tormek; I am just curious. I am well aware that the answer may be "It depends", factoring in the application and species of wood.
Ken