M2 Steel Tools vs. 10V Steel Tools

M2 Steel, also called High Speed Steel, or HSS, is today's standard for Woodturning tools. It is a steel alloy that holds a sharp edge a long time, handles heat well,
and is easy to sharpen. M2 is a specific alloy of steel, being a combination of metals in a precise ratio. The heat treating process is what gives M2 its edge-holding ability. Proper heat treating is a very exacting process involving heat, temperature, and time. Top quality tools made from M2 HSS are accurately heat treated according to precise specifications. Heat treating can easily be done poorly, or improperly. An low quality M2 tool might have the correct alloy composition, but not have the edge holding performance that it would have gotten from proper heat treating.

This is why when we buy "off brand" (usually low cost) turning tools, sometimes we get a good one and sometimes we don't. What we get with top brand premium M2 tools is an alloy of the correct composition that also has been properly heat treated. This usually comes at a premium price. The easiest way to lower tool manufacturing costs is to make them in less developed countries and skimp on the heat treating.

M42 Steel is also a conventional High Speed Steel like M2. It has a higher cobalt content than M2, and some people feel that it holds an edge longer than M2. I am not sure that it is better than M2, but it seems to be comparable and makes an excellent woodturning tool. D-Way and Carter and Son make top quality M42 tools for woodturning, and they are both made in the USA.

10V, or A11, Steel is considered a Tool Steel. In the metalworking world, it is not usually used for cutting tools. It is very tough and durable. Everything that I said about the precise alloy composition and accurate heat treating of M2 applies to 10V (A11) as well. The two metals are very different, however. 10V is made using a process called "powder metallurgy", where the final product contains very fine particles of carbides.

Other powder metal tool alloys commonly found in woodturning tools are ASP 2030/2060, M4, and 15V. The extra hard carbide particles are what make powder metal tools hold an edge significantly longer than M2. 10V contains 10% Vanadium Carbides, 2060 has 7.5% Tungsten Carbides, and M4 has 4% Tungsten Carbides. The 15% Vanadium Carbides in 15V allow it to hold an edge even longer than 10V, but the edge is more brittle and can fracture more easily, making it less desirable for woodturning. I believe that 10V is the best compromise. Thompson Lathe Tools are the only current production turning tools made from 10V. My signature tools are made from Thompson 10V, or Carter and Son M42.

Powder metal tools, such as 10V, do hold an edge significantly longer than M2 tools in my experience. But it performs best if it is sharpened properly. The hard carbide particles need to be sharpened with something harder than they are. If they are not, the carbide particles are not able to be formed into a part of the edge. Instead of being abraded into a sharp edge, they are knocked out of the matrix resulting in an uneven cutting edge, and end up doing very little to help the tool hold a sharp edge longer. This is why a lot of turners feel that powder metal tools don't initially get as sharp as M2 tools. They are usually not using an abrasive that will put an edge on the carbide particles.

Sharpening

Aluminum Oxide is softer than Carbide particles. The "white" wheels that came with your grinder are low quality aluminum oxide wheels. The "Pink" wheels, and some "blue" wheels, are also Aluminum Oxide. Norton and OneWay (among others) make excellent quality Aluminum Oxide grinding wheels. They still are not capable of forming an edge on carbides, and won't give you peak performance from your powder metal tools.

CBN, Diamond, and Ceramic are harder than Carbide, and can form a sharp edge on powder metal tools. D-Way and Opti-Grind make CBN wheels for woodturners. WoodRiver (sold at Woodcraft) and D-Way make Diamond wheels for woodturners. Norton SG wheels are 50% ceramic, their 3X wheels are 30% ceramic.
Sharpening with fine grit seems to make more of a difference in the quality of the cutting edge on 10V than it does on M2.

How do I choose between M2 Steel Tools and 10V Steel Tools?

In my opinion, the improved edge holding performance of 10V is most noticeable in a negative rake scraper. Even sharpened with fine grit regular Aluminum Oxide. I liked the 10V scrapers even more when I started sharpening with a Norton 3X, 120 grit wheel.

It wasn't until I started sharpening with a fine grit CBN wheel that I fell in love with 10V gouges. With the 3X wheel, I didn't feel like my 10V gouges got as sharp as M2. The edge on a gouge seems to be more sensitive to being sharpened properly. Honing with a diamond hone is another way to get a sharp edge on 10V.

Here's my recommendation:

If you sharpen with fine grit (100 or finer) Ceramic (Norton 3X), buy 10V scrapers and M2 gouges. You will be pleased with their performance.

If you sharpen with CBN, buy 10V gouges and 10V scrapers. You will love their performance!

If you sharpen with the white wheels that came with your grinder, and don't want to buy new wheels, buy M2 gouges.

If you hone with a diamond, you will probably love 10V tools, too. My 10V Vortex Tool is sharpened with a diamond hone. The performance of 10V is noticeable on the Vortex.