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:

 

[John Brown]

I made my own gouge sharpening jig, using a template from the internet. Works fine.

I know this is a fairly old thread, but..
Having made something functionally similar, I'm looking for advice on how to set this up. There are four variables, as I see it: the length of gouge protruding through the jig, the angle of the "stick" to the jig, the position of the sliding bar support, and the length of the stick (granted - this ceases to be a variable at some point in the build process). How do I go about finding a configuration that works for my gouge? Is it just trial and error? I do hope not..

 

[Phil Pascoe]

Basically, yes it is. When you get it right glue or screw a little stop block on the base of your grinder (or edge of shelf, anywhere convenient) so you get exactly the same protrusion every time you grind. Asssuming you alter nothing anywhere else you'll grind perfectly in one pass. You can use different stops for different gouges. I use Sorby 447s and it takes about 20 seconds to put a perfect grind on a spindle gouge, and wastes not much more than a few thou of steel.

 

[Robbo3]

I know this is a fairly old thread, but..
Having made something functionally similar, I'm looking for advice on how to set this up. There are four variables, as I see it: the length of gouge protruding through the jig, the angle of the "stick" to the jig, the position of the sliding bar support, and the length of the stick (granted - this ceases to be a variable at some point in the build process). How do I go about finding a configuration that works for my gouge? Is it just trial and error? I do hope not..

Yes, you have got it right, there are 4 variables. Unless you know what you want the end result to look like, stick to the angle already ground on the gouge.
Some set ups eg Sorby, Tormek etc. have a fixed distance between the jig & the wheel/belt.
Perhaps this Tormek guide will help.

 

[John Brown]

Yes, you have got it right, there are 4 variables. Unless you know what you want the end result to look like, stick to the angle already ground on the gouge.
Some set ups eg Sorby, Tormek etc. have a fixed distance between the jig & the wheel/belt.
Perhaps this Tormek guide will help.

Thanks, although the thing I made is obviously slightly different, I will take a look at the Tormek guide, as no doubt some of the principles will still apply.