A2 steel plane blades

[george wilson]

Thanks for the clarification.

[Jim Paulson]

I feel very fortunate that you folks were willing to give me your perspectives and offer up pertinent research on this question. I also appreciated Jim's discussion on sharpening A2 steel on the Veritas Mk.II Power Sharpening System. Since I love using the worksharp, it was encouraging to hear that I could handle the A2 as well. You have given me some ideas about the various stones I could utilize after honing on the worksharp.

As someone who is no stranger to using ceramic, water stones, and diamond stones for sharpening, I really benefitted from all your insights here. I have a greater awareness too of the knowledge base you provide this forum.

Many thanks for your helpfulness,
Jim

[Sandy Stanford]

Hi creekers,

I've got a 605 bedrock plane that I'm restoring to use with a shooting board. The plane cleaned up real nice and the only thing I'm changing on it is to add a replacement blade and maybe a new chip breaker. I want to beef up the iron thickness with a Hock blane. What do guys recommend on the blade steel? My preference has always been to get my cutting edges razor sharp, can I get that with A2 steel or should I stick with my gut and go with O1 steel?



http://www.chairsbypaulson.com

I'm absolutely convinced that I cannot get A2 to as sharp a state as O1. I've been at this game a while. No A2 for me. Further, I don't like having my sharpening media dictated to me by the steel.

[Andres Sender]

Since my favorite blades are M3 and my aspirations currently point more towards M2 and Japanese steels, I don't have much to add directly to this question, but I think Brent Beach's plane blade tests provide some useful data points. To me the differences between O1 and A2 seem relatively subtle, although as time goes on I am less and less a fan of run-of-the-mill O1 (which Lie-Nielsen isn't).

http://www3.telus.net/BrentBeach/Sharpen/bladetest.html

I can't resist indulging in a brief philosophical detour however: if you’re not letting your steel dictate your sharpening equipment, then you are effectively letting your sharpening equipment dictate your steel, which in terms of practical effect is potentially even more limiting.

I don’t mean that as an assault on anyone’s preferences. Many factors affect one’s choice of tool and I have great respect for many craftsmen who have mastery with very different tools.

[Sandy Stanford]

Since my favorite blades are M3 and my aspirations currently point more towards M2 and Japanese steels, I don't have much to add directly to this question, but I think Brent Beach's plane blade tests provide some useful data points. To me the differences between O1 and A2 seem relatively subtle, although as time goes on I am less and less a fan of run-of-the-mill O1 (which Lie-Nielsen isn't).

http://www3.telus.net/BrentBeach/Sharpen/bladetest.html

I can't resist indulging in a brief philosophical detour however: if you’re not letting your steel dictate your sharpening equipment, then you are effectively letting your sharpening equipment dictate your steel, which in terms of practical effect is potentially even more limiting.

I don’t mean that as an assault on anyone’s preferences. Many factors affect one’s choice of tool and I have great respect for many craftsmen who have mastery with very different tools.

That's a set up for a grand game of tail-chasing, an activity in which I have no doubt many are more than willing to engage.

[george wilson]

I like A2 just fine,but for the projects I have posted here,I used 01 and W1 steel blades. it doesn't really matter what tool steel you use. It is your skill that matters. For production situations like my punch press stuff,it is a different matter,and I much prefer the longer lasting metal so I don't have to replace punches and dies when I'm too old to do it well anymore.

[Wes Grass]

'Adhesive wear'. On wood? Seriously?

I think they're talking about galling.

As for A-2, I too have made a bunch of tooling from it. Hard to grind? Try some Graph-Mo from Timken ;-)

[Bob Glenn]

Ah, George, I respect your experience and knowledge greatly, however, with a wife nineteen years younger than you, why are you spending so much time jousting here about tool steel? You didn't think you could slide that by us with out at least one comment, did you?

BTW, I just had some A2 hardened and it is a complicated process.

Thanks for all your input to this forum.

[Leigh Betsch]

I built a bunch of blades out of A2 and had them professionally heat treated and cryo treated. I'm not going to take the time to do a real study on what type of steel is best for plane irons, so I jumped in and went with A2 based on my toolmaker days. But what do you experts think of D2? I avoided it because I'm really not set up with the proper tooling (carbide and coolant) to mill and grind it at home. But it seams to me it would make a great plane iron if a person wanted to put the effort into it.

[george wilson]

I have made knives out of D2. It is very tough to machine with its approximate 12% chrome,and other alloys. Not quite enough chrome to get it into the stainless steel category. It is also a steel that can be brittle. It has the peculiar trait of not feeling as sharp as it really is. I can only sharpen it with diamond stone,followed with a black and a white ceramic stone. Other stones I used to use weren't hard enough to get it razor sharp.


You don't want to go twisting on a D2 blade.

D2 was developed as a highly wear resistant steel for steel shearing blades. It has a feature of showing multi layered triangle shaped crystalline structures in it when it is mirror polished.

I think that A2 is going far enough for plane irons,myself. The longer the blades wear,the more time they take to sharpen.

Steels like high speed steel have too coarse a grain structure to get as sharp as simpler steels.

As for my wife,it's my age,not hers that keeps me here!! She wanted an artist husband.

[Larry Frank]

I have been reading this thread with some interest. It should be noted that A2 tool steel is a very complex material and sensitive to how it is heat treated. Granted this seems a bit of a strange statement for material that hardens in air. However, the subsequent treatments such as anneal or cryogenic cooling have a large impact on the final properties. Without extremely careful treatment, the material could have quite a wide range of final properties. The same comments can be made for all of the tool steels. One is really left with trusting a good name producer of tools to make certain that the material has been properly treated.
The term HSS or high speed steel also has a very large range of compositions and potential variations in properties. Without knowing exactly which HSS you are dealing with and how it was heat treated, it is not possible to even begin to generalize on its properties or how it might work in a woodworking situation. If someone is curious about some of the compositions, you could look it up in the Wkipedia or some of the other sources that you would find with a general search.
Most people are not really interested in the exact composition or how a steel is heat treated but only the final properties. With my background as a metallurgist, I do find it interesting. However of more importance to me, I just want a blade that is sharp, reasonable to sharpen and consistent in properties. It appears for my uses that A2 makes very nice shavings and produces a good surface on the wood.

[Jim Paulson]

Being a former geologist and an amateur blacksmith, I've really enjoyed the input provided here. I'm fascinated with metalurgy and I'm on the same page with Larry. I am more interested in purchasing a blade that was carefully treated by others and one that I can make sharp.

Since I don't have a microscope to look at the steel or the time to do that, I'm glad others have done that kind of research. Bottomline, I'm going to give the A2 a try in my Bedrock 605, but when it comes to making my own blades to be used in wooden molding planes I'll have to stick with O1.

Jim

http://www.chairsbypaulson.com

[James Carmichael]

Oye! Here we go again! May I recommend to the moderators that we post this as a sticky?

A2 is harder and will hold an edge longer. The tradeoff is that it is more difficult to sharpen, and it usually costs a little more.

Unless you're opening a 19th-century cabinet shop where you will be planing 100s of BF of rough lumber every day, either iron will serve you well and will outlast you.

[Ron Hock]

Here's the "official" line regarding O1 and A2 from Hock Tools: http://www.hocktools.com/A2.htm

The only thing mentioned in this thread that I must correct is the misconception that A2 is "harder" than O1. A steel's hardness is a function of the heat treatment process and either one can be tempered harder or softer by choice. A2 is "tougher" -- less brittle -- than O1 (at the same Rc hardness) which accounts for its edge retention reputation. I know it's a fine point but that's where this discussion ends up: two great steels differentiated by their fine points.

[george wilson]

Yes,any steel is as hard as you leave it from tempering. W1 will actually get harder than anything else I have used. It will reach 67 RC,if I recall correctly.

However,excessively hard steels don't hold an edge too well because they are also too brittle,and the tiny edge breaks off.

60 RC is too hard for 01,in my opinion. I made a blade of 01 and tempered it at 60 RC. It never kept a good edge. 58 is a better figure,or even 55.