Pole saw blade sharpening?

[pdqdl]

The diamond file doesn't cost much, and would laugh at the hardness of the hardened blades.

Funny thing about diamonds as an abrasive: they don't work nearly as well on soft materials as they do on harder ones. For the most part, diamond wheels don't get used on steel, 'cause it is too soft, makes too much heat, and rubs the diamonds out of their matrix attached to the wheel. For reasons unknown to me, the CBN wheels don't seem to have that problem, but they cannot be used on carbide teeth. Obviously, diamond wheels are the best option for carbide tools.

 

[nedsim]

The diamond file doesn't cost much, and would laugh at the hardness of the hardened blades.

Funny thing about diamonds as an abrasive: they don't work nearly as well on soft materials as they do on harder ones. For the most part, diamond wheels don't get used on steel, 'cause it is too soft, makes too much heat, and rubs the diamonds out of their matrix attached to the wheel. For reasons unknown to me, the CBN wheels don't seem to have that problem, but they cannot be used on carbide teeth. Obviously, diamond wheels are the best option for carbide tools.

The reason that diamond wheels should not be used to grind steel is that at the temperatures developed iron has an strong affinity for carbon and will "dissolve" the diamond crystals. This is not an issue with a hand file, but you may clog a fine diamond file working soft steel, much like aluminum or copper will clog a fine file. A chainsaw tooth is relatively soft, but the hardened teeth on the handsaws being discussed are of similar hardness to high speed steel metalworking cutters.

https://insights.globalspec.com/art...-super-of-a-material-diamond-materials-part-1

Ferrous Alloys are Diamond’s “Kryptonite”​

Diamond does have a drawback in machining and abrading certain metal alloys. For example carbon, and therefore diamond, dissolves in iron at the high temperatures at the workpiece to cutting-edge interface, which makes diamond ineffective in cutting ferrous alloys (steel, stainless steel, cast iron, superalloys, etc.). Diamond also reacts with cobalt, nickel, chromium, and vanadium under the high temperatures generated in the grinding processes. Diamond’s sister superhard or superabrasive material, cubic boron nitride (CBN) is used to grind iron, cobalt and nickel-based alloys. CBN can also withstand higher temperatures before degrading. Norton Abrasives' Diamond and cBN Superabrasives catalog contains additional information on the differences between and selection of these two superhard abrasive

 

[pdqdl]

I never knew that. Makes perfect sense, though.

While my observations seem to have been correct, I never knew the carbon was being "dissolved" into the steel.

 

[Philbert]

What’s the difference between ‘ABN’ and ‘CBN’?

Thanks!

Philbert

 

[pdqdl]

I think ABN is the older term. My wheels long ago were ABN, and they became CBN. I'll do some research...

 

[pdqdl]

I was kinda right, but there are actual differences.

"Full names:ABN: Aggregated Boron Nitride

CBN: Cubic Boron Nitride"​

"ABN: Typically made by sintering boron nitride powders

CBN: Synthesized under high pressure and temperature conditions"​

​

Basically, pretty similar stuff, but the CBN is better, a bit more expensive, and lasts longer. The ABN is indeed older technology, mostly because it took them time to figure out how to make the Boron Nitride particles big enough to call them "Cubic"

I also discovered a very cool factoid: some folks might know that Diamonds have both the hardest molecular structure and also the very highest thermal conductivity. A diamond frying pan, for example, would transfer heat about 5 times faster to your bacon than would a copper frying pan.

Cubic Boron Nitride (CBN) is the second hardest known material, and also the second best known at conducting heat.

Hmmm... I'm gonna do some electrical conductivity research now.

EDIT: Yes, CBN is right behind diamond on electrical resistance, but both are a bit lower resistant to electricity than Teflon and a few other molecules.