Tool Steel or ?

[Tom Albrecht]

I believe we are told not to use the CBN grinding wheels on anything other than hardened tool steel. I know that I shouldn't grind steel bolts, or brass, or copper because it will clog the CBN wheel and render it useless. I know that the turning tools I bought over the years are various HSS, except for maybe the very first set that came with a lathe package back in 1970 or so. But how can I know about the hardness of various steels that I may come across? Is there a simple way that a layman can test it to verify?

 

[Tim Connell]

Quick and simple is to take the edge of a file and see if it will bite the steel you are "testing". If it bites, not hardened. If it skates across without biting, the steel has been hardened.

Not a quatitave test, but should separate hardened steel from non-hardened.

 

[Owen Lowe]

I believe the last time this came up, word came down (the guy who started D-Way?) that any hardened steel is fine to sharpen on CBN. High-carbon steels, high-speed steels, and crucible steels are all A-OK. Non-ferrous, low-carbon, and carbides are not to be ground on CBN.

 

[john lucas]

I have.been sharpening some high carbon steel tools on my CBN wheels with no problems. I would not use it for soft metals like brass and copper and probably not non hardened steels. The skating file test is pretty accurate.

 

[Tim Connell]

Know of several hand tool woodworkers use CBN to put a hollow gring on all their plane blades and chisels. Makes it easier to hone blades without guides. Those are all tool steels, O1, W1, A2, etc. but are not HSS.

 

[Tom Albrecht]

Thanks all.
Got it.

 

[odie]

Now that Tom has his answer......I'll add that I still have my first 6"/3450rpm grinder. I started out sharpening lathe tools on it, but upgraded about 20 years ago. I now do all my "garbage grinding" here. Great to have it as a back up......
-----odie-----

 

[robo hippy]

I think I have said this before, but can't remember.... I did a test on an old D Way wheel that was pretty much worn out, which is about 5 years worth of production turning. I intentionally loaded it up with aluminum, copper, brass, and some mild steel. With a little lapping fluid and about a month more of sharpening scrapers on the wheel, all visible traces of those metals were gone. If you are sharpening a softer metal on your wheels, you can feel them loading up. There is a bumping/ticking that you get as the tool hits the build up on the wheel. A good M2 or M42, or V10 scraper will take that all off. I do know that there are 'cleaning sticks', which I believer are a very hard aluminum oxide, harder than our standard AlO wheels, that can also be used to 'clean' the wheel. They do put a lot of dust into the air...

robo hippy

 

[john lucas]

Odie I still have my Craftsman 6" and it still has the same gray rough wheel on one side. I had a white wheel on it when I got serious about sharpening lathe tools. I've since replaced that with a green wheel for sharpening my metal lathe t