Sharpening

[stateit]

Has anyone risked trying one of the cheap 150mm CBN wheels(around the £30 mark) from Amazon or AliExpress?
There are not enough reviews on Amazon so far to get an idea.

I think you'll find those are actually diamond wheels. The heading may say CBN, but the small print says 'diamond'. Rather like I bought some supposed tungsten carbide rods recently, that were very attractively priced, to find them stamped 'HSS' when I received them...

I have however purchased a £70 CBN 150mm wheel (the ones branded 'UF-SHARP), which took a little while to arrive, and I am more than happy with it. Very happy. When you look at them and compare them to ones sold by Rutland, Charnwood, Axminster etc, you may find a surprising similarity. Except for the markup in price. We don't make CBN wheels in this country - they're all Chinese made....

 

[Vulcan]

I’ve also noticed many of the cheap ones are described as “CBN Diamond” you don’t know what you’re getting.

 

[John Brown]

I think you'll find those are actually diamond wheels. The heading may say CBN, but the small print says 'diamond'. Rather like I bought some supposed tungsten carbide rods recently, that were very attractively priced, to find them stamped 'HSS' when I received them...

I have however purchased a £70 CBN 150mm wheel (the ones branded 'UF-SHARP), which took a little while to arrive, and I am more than happy with it. Very happy. When you look at them and compare them to ones sold by Rutland, Charnwood, Axminster etc, you may find a surprising similarity. Except for the markup in price. We don't make CBN wheels in this country - they're all Chinese made....

I see, are they useless, then?

 

[Vulcan]

I see, are they useless, then?

No, they will still work but CBN is better for some materials. I saw a chart somewhere detailing the difference, I’ll try to find it.

 

[John Brown]

No, they will still work but CBN is better for some materials. I saw a chart somewhere detailing the difference, I’ll try to find it.

Right I wanted to sharpen turning tools.
Seems wrong to call it CBN if they're not, but that's the world we live in these days...
Just wish I'd bought from Amazon, rather than AliExpress, as I'd be able to return it!
Live and learn!

 

[Vulcan]

This is the Graphic I saw a while back. Tormek sell Diamond wheels for their grinders so I’m none the wiser.

Edit: Some more information here:

https://info.eaglesuperabrasives.co...nding wheel,deterioration of the diamond grit.

 

[Sideways]

Simplistically, CBN for sharpening high speed steel tools, diamond for sharpening tungsten carbide cutting tools.

Diamond is harder than CBN, but CBN is a far better conductor of heat than diamond so in moderation, it can be used dry without overheating the steel.

Don't use soft sticky stuff on either, it will gum your wheel up.
Tormek should be the experts, not me, but I wouldn't put aluminium to either wheel. TBH, I wouldn't buy a CBN wheel to sharpen carbon steel. These wheels are hard and they cut cleanest on materials that are also hard, just not AS hard.

 

[John Brown]

Thanks.
Oh well, I guess I'll just put it in a drawer, just in case a find some use for it someday...

 

[bentontool]

Simplistically, CBN for sharpening high speed steel tools, diamond for sharpening tungsten carbide cutting tools.

Diamond is harder than CBN, but CBN is a far better conductor of heat than diamond so in moderation, it can be used dry without overheating the steel.

Don't use soft sticky stuff on either, it will gum your wheel up.
Tormek should be the experts, not me, but I wouldn't put aluminium to either wheel. TBH, I wouldn't buy a CBN wheel to sharpen carbon steel. These wheels are hard and they cut cleanest on materials that are also hard, just not AS hard.

I have been using CBN wheels on my tools (chisels, gouges, plane irons; both HSS & tool steel) without any issues. I am sure all my tool steel is above 45 Rockwell C scale hardness. See below: