The Rapidly Rising Cost of Steel

July 3rd, 2012 by
4 Comments

I remember the halcyon days when M2 high speed steel (HSS) turning tools hit the market. No longer did we have to worry about burning at the grinder, and HSS tools held an edge forever — compared to plain carbon steel, anyway.

The last decade has seen a proliferation of turning tools made from exotic powdered steels. Powdered refers to the manufacturing process where iron, with the necessary alloying elements, is mechanically mixed in powder form, then sprayed into a furnace where the powders become plastic but do not melt. The resulting blob is cold worked to form bars for machining. Powdered metal technology allows much higher amounts of alloying metals such as vanadium (which increases edge holding) than conventional blast furnace manufacture. The price of such special handling is significantly higher, but PM steels give extraordinarily longer tool life for metal cutting.

I have long suspected that the metal cutting claims were accurate but did not hold true when cutting wood. In fact, for spindle turning, I feel a good old M2 gouge may hold an edge longer than PM tools. I am speaking from gut experience for I am fortunate to have tried about every new tool on the market. A second factor is that a new turner is going to grind up a tool or two in the “learning to sharpen” process so, for your first couple of tools, the grinder is the enemy and the cheaper the better!

A study James T. Stanley did with his engineering students at North Carolina State University at Raleigh in 2008 confirms my intuitive reaction. Those wanting to read this fascinating paper, can download it here. The study does confirm improvement in edge holding of PM tools when cutting wood but nowhere near the claims for metalworking. For bowl turners who know how to sharpen, the extra price may be salient.

I feel spindle turners are better off with M2 as it takes a keener, burr-free edge more readily. For scrapers, which are used by both spindle and faceplate turners, M2 is vastly superior to carbon or PM steel. Sorry to steal the PM thunder, but that is the way I see it, and I hope I have saved you a buck along the way.

Ernie Conover

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4 Responses to “The Rapidly Rising Cost of Steel”

  1. Dennis Blades says:

    Over here in the UK thanks to 20% VAT the price of turning tools have got to the point where I can’t justify the cost just for my hobby. It is not just the tools, the price of wood for turning
    as got to point where I will not buy it but I still love my turning and I will continue. I have been lucky just lately as one of my friends as just cut down to old Apple trees so I have a good stock of wood to keep me going for a bit and I keep my ears open for the sound of a chainsaw.All the best to wood turners every where and keep turning.

  2. Paul A. Otto says:

    I enjoyed your blurb on PM metal turning tools vs HSS. As an avid wood turner (bowls and pepper mills especially) and retired engineer from a long career in the metal cutting tool industry I would tend to agree that PM steel does not offer much of an advantage in wood turning. At least not enough to justify the additional cost.

    On the other hand I now use tungsten carbide indexable insert tools for bowl turning and wood composite pepper mills which are especially hard on tools. These carbide insert tools offer a tremendous value in time saving especially in roughing operations. They remove material so fast that it becomes neccessary to wear thin leather gloves while roughing a dry hardwood bowl blank in order to protect your hands from the hot chips. You can literally bury yourself in chips if you have a sufficiently powerful lathe. There is no need to sharpen carbide tools because they use an indexable carbide insert that offers four edges or a round insert that lasts a very long time. In order to grind carbide, a diamond grinding wheel is needed to achieve the fine finish to produce a sharp edge. I do not regrind these inserts but I will touch them up with a diamond hone to extend the life. If you turn dry hardwood bowls you owe it to yourself to try this tool.

  3. metsch says:

    Fascinating report, but what is triple tempering???

  4. Lyndsay says:

    Interesting. I didn’t realize that steel prices were going up as well as everything else. I appreciate your background information on these tools.

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