I am getting a mini-lathe and eventually will be shaping and sharpening
tools so I searched the web for info on grinding wheels but have some
confusion.

Please fill in and correct.

I have a 5" grinder with coarse and fine GRAY wheels, I think that is
Aluminum Oxide and is good for HSS.

5" Aluminum Oxide wheels are difficult to find let alone any other abrasive
type.
If you know a source, please share.

For sharpening Carbide Tools I need a Silicon Carbide wheel which is GREEN.
Right?
I read that Silicon Carbide is not indicated for ferrous material.
I have used a flat Green stone to sharpen wood cutting chisels and plane
irons for years.
Either is OK for steel or green does not necessarily equate to Silicon
Carbide.

I see BRICK RED stones, often used for wet grinding of wood cutting tools,
usually finer that the GREEN stones. What material is that? What is it
best for?

I also see wheels WHITE in color that looks like made of sugar cubes, what
material is that? What is it best for?

I summary I like to be able to associate color and material assuming that is
possible and for each type of tool material what is the proper grinding
stone.

Also, HSS should be honed with a diamond hone. I have seen diamond hones in
the shape of blocks which seem impractical to rub the tool on the block
rather than have a hone similar to a file that you move on a fixed tool.
What do you use for this?

An then there are the ceramic...

Thank you for your help.

Mauro Gaetano

MG wrote:

I am getting a mini-lathe and eventually will be shaping and sharpening
tools so I searched the web for info on grinding wheels but have some
confusion.

Please fill in and correct.

I have a 5" grinder with coarse and fine GRAY wheels, I think that is
Aluminum Oxide and is good for HSS.

A 5" bench grinder is likely to be a complete misery. My first suggestion is
that you scrap it and get an 8" one on your local craigslist. Bench grinders are
ubiquitous and dirt cheap. Make certain you see it run and that it runs smoothly
and that it comes with all of its parts. Actually, try to find a grinder with a
5/8" shaft instead of a 1/2" shaft. That will likely rule out the tiny ones.

A gray wheel is likely a very hard aluminum oxide wheel. Yes, AlOx is suitable
for tool steels. However, the first thing to learn in Abrasives 101 is for soft
metals you need a hard wheel and for hard metals you need a soft wheel. HSS is
hard, and so you need softer wheels.

5" Aluminum Oxide wheels are difficult to find let alone any other abrasive
type.
If you know a source, please share.

Grinding wheels are really cheap. MSC, Enco, J&L, places like that.

For sharpening Carbide Tools I need a Silicon Carbide wheel which is GREEN.
Right?
I read that Silicon Carbide is not indicated for ferrous material.

Right. I have had a home shop since the mid-'80s and have yet to need to sharpen
carbide, however. I use some carbide tooling, but it's either indexable inserts
or brazed carbide bits I got for nothing and if they go bad I toss 'em. I
suggest you forget sharpening carbide until and unless you have a real need.

I have used a flat Green stone to sharpen wood cutting chisels and plane
irons for years.

A hand stone? Who knows what it is?

Either is OK for steel or green does not necessarily equate to Silicon
Carbide.

I see BRICK RED stones, often used for wet grinding of wood cutting tools,
usually finer that the GREEN stones. What material is that? What is it
best for?

??


I also see wheels WHITE in color that looks like made of sugar cubes, what
material is that? What is it best for?

Probably aluminum oxide again.

I summary I like to be able to associate color and material assuming that is
possible and for each type of tool material what is the proper grinding
stone.

Call MSC and ask them to send you a Norton catalog. Or just google on grinding
wheels, jeez, in ten seconds you should find everything you want.


Also, HSS should be honed with a diamond hone. I have seen diamond hones in
the shape of blocks which seem impractical to rub the tool on the block
rather than have a hone similar to a file that you move on a fixed tool.
What do you use for this?

I disagree again, sorry. Diamonds, being carbon, dissolve readily into steel. I
use Gesswein hand stones, Wa****a stones, Arkansas stones and the like for hand
honing.

An then there are the ceramic...

Thank you for your help.

Kudos to you for asking. That's how you learn!

GWE

MG writes:

For sharpening Carbide Tools I need a Silicon Carbide wheel which is
GREEN. Right?

You want a diamond wheel. $$$ Green wheels are a distant second place.
But nothing else even finished.

The wheel that goes on the Twice as Sharp scissor grinder is a 5" I
hardness 100 grit .
Order one from Wolff industries it's a pretty good all around wheel for
steel small tools.
As for green or silicon carbide it will shape a carbide tool but you
still need to follow up with diamond.