Cubic Boron Nitride Rods for Sharpmaker

mrdabble

mrdabble

Joined
Jan 23, 2014
Messages
928
Any good? I just got my sharpmaker a couple weeks ago and I'm gonna put in an order for diamond and extra fine stones, should I grab these as well? Or will the diamond be sufficient alone? I've had fantastic results already but I haven't done any high vanadium steels yet.
I also see that they are new, has anyone had experience with them yet at all?
 
I wouldn't think they would do anything the diamond stones won't do. CBN is softer than diamonds.
 
Their only advantage to diamonds seem to be chemical and thermal stability, neither of which really apply to sharpening stones so I really dont get the point of these?
 
The grit size is finer than the diamond coated prisms, but the CBN is co-deposited onto a hollow steel prism with electroplated Nickel. So you have a deposit that you can't lean on (press hard), but it is softer than diamond.:eek: I would like a couple of solid sticks of Cubic Boron Nitride so I could sharpen knives fast like I do on my Corundum and Carborundum stones.
 
There are a couple reviews of them on spyderco's forum and another forum. Not sure how the mods here feel about posting links to none supporting forums though. Figure spyderco is ok since the have their own sub forum here. From what i've seen and read, i would get the cbn's. They hold up well and cut fast. With a consistent grit range. Also, saying cbn is softer than diamond is like saying lightning is hotter than the sun when you're trying to light a candle. At that point, not much reason to make the distinction except to nit pick. Also, you can increase speed instead of pressure to cut faster. Increasing pressure is never a good thing. Heavy burrs, fatigued metal, worn grits(electro plate or solid stone) and heat build up. You can get heat build up by increasing speed but you won't wear the grit as fast so you don't build up as much heat. Also, lube.
 
They are supposed to be less prone to fracturing (tougher). They seem to work well when compared to diamond bits on a small air drill. But that is a much more intense than sharpening. I also read that they do not cause streaking (carbon deposition) on steels that (I guess) diamonds can????

Last year I was looking for belts with CBN. They were listed but not available.
 
Cubic Boron Nitride has a Vickers hardness of 48. Diamond has a Vickers hardness of 115. The Vickers hardness range is proportional, so Diamond is 2.4 X as hard as CBN.
 
tiguy7 said:
Cubic Boron Nitride has a Vickers hardness of 48. Diamond has a Vickers hardness of 115. The Vickers hardness range is proportional, so Diamond is 2.4 X as hard as CBN.
Click to expand...

fervens said:
True, but where is steel and vanadium carbide?
Click to expand...

CBN is still 15-20% harder than vanadium carbide (which is harder than silicon carbide, which is harder than aluminum oxide). Hardened steel for cutlery isn't even a factor by comparison to any of them. In other words, for sharpening knives of any kind, I'd think CBN is still plenty hard enough.


David
 
So essentially if you already have the diamond triangle these would be an un-needed expense/accessory.
 
Except they are finer grained than the diamond coated prisms and coarser grained than the tan prisms. They fill the gap.
 
You must log in or register to reply here.
Back
Top