HSS qualities

[Wally Crawford]

I have been using Hurricane branded M42 cryo treated bowl gouges, but am considering a new gouge. I see that Thompson Tools offers a different steel and, of course, they promote their differences as being better. There is not a huge difference in price between what I have been buying and the Thompson Tool, but my question for this group is the difference really there? I am reasonably sure that some of you have tools similar to my current tools and may also have used or own a Thompson gouge.

What is your experience? Is the cost difference worth it?

[roger wiegand]

I have tools from Thompson, Sorby, Hamlet, D-Way, and Taylor. I'm not sure which are made from which steels. None, to my knowledge, are cryo treated. The only ones that seems to stand out for me are the Thompson bowl gouges, which seem to go a lot longer between sharpenings-- certainly not a scientific study, though. I much prefer the finish on my D-Way skew to the rough, sharp corners that the Thompson comes with-- it takes a lot of prep work to make a Thompson skew useable, but once that's done they work just fine. All of these tools are perfectly serviceable. I would say that Thompson is my current default source, in part at least because I like being able to talk to the guy who is making my tools.

[Adam Wager]

Thompson tools, like most powdered metal tools are given a cryo treatment as part of the heat treatment process.

This topic comes up fairly often and the general trajectory is that on paper the 10v steel used in Thompson tools and some others has slightly better wear resistance that the M42 used by DWay, Crown and some others. I have used both and don't notice much if any real-world difference between them, but both have significantly better wear resistance than standard M2 HSS (or even cryo treated M2 steel - beware of the difference between cryo m2 and cryo M42). Differences in silica content in the wood, amount of gritty bark being cut through, and type of cut have much more impact for me on how long an edge lasts.

In these discussions one will also often find the claim that M42 takes a keener edge than 10V. I have not seen any hard evidence in support of this when both are sharpened on CBN wheels - though my searching has not been exhaustive. The vanadium in 10V is too hard to be sharpened by conventional abrasive wheels so those vanadium carbides will tend to get knocked out of the tool rather than sharpened when using traditional grinding wheels. These vanadium carbides can be fairly large depending on the exact manufacture/tempering process, possibly up to 10 microns which is about the equivalent of the particles in 1800 grit abrasive. From a perfectionist handtool sharpening perspective, an 1800 grit edge is not as sharp as one can get. This may be the source of that keener edge claim. If you are sharpening with CBN wheels then I doubt you will notice any difference in sharpness between 10V and M42. Unless you are doing production runs of identical turnings out of identical material, I doubt you will notice any difference in edge retention between 10V and M42. I would let flute shape (which can vary a lot from manufacturer to manufacturer), price, fit & finish, and any other practical or ethical considerations guide your decision.

[Reed Gray]

I have been using Thompson and D Way tools for years. Both can be sharpened on standard wheels, but I have had CBN wheels almost as long as I have had these tools. As far as edge sharpness and edge durability, I can't tell any difference. A friend who production turned for 30+ years agreed that there was no difference.

robo hippy

[John Keeton]

Metallurgy data would indicate that M42 may be slightly more susceptible to micro edge chipping if the wood contains high silica content. I have used D-Way and Thompson for over a decade and that seems to be accurate. However, both are fine steels and that difference is not a factor for me. I like certain flute profiles for different uses and that is a more important consideration.

[Edward Weber]

Well count me in with the no difference group.
The may be technical issues that might indicate one has better wear, or one is less brittle, etc.
That being said, after fielding questions from woodturners for over ten years on another forum, the real world "differences" are imperceptible to most. To others, it's more a matter of personal preference than anything else.
I have personally used many HSS varieties and while I have many Thompson tools, other makers offering their own M42 alloys are also in my arsenal.
Here's a link to an easy to understand HSS properties chart
https://hudsontoolsteel.com/site/CompareHighSpeedSteel

[Wally Crawford]

Thanks guys, and sorry to re-hash familiar territory. I do sharpen with CBN wheels and a OneWay system, but I turn a lot of Hickory and Pecan and both are tough on an edge. The Hurricane brand tools I use have a "U" or parabolic shape and I have never tried any other flute shape.

Thanks again for the thoughts.

[Richard Coers]

I've been turning for 37 years and I can tell when I use one of my Thompson gouges. I sharpen them in the JoHannes Michelsen grind. I haven't used any of my old gouges for the last 15+ years since I bought the Thompson gouges.