Which Steel for a plane blade

[Bob Johnson2]

Ordering the Veritas LA Jack, it comes with either A2 or O1, which of the 2 is preferable for plane blades? I'll be ordering the 38 degree bevel too if it would make a difference.

Thanks
Bob

[Michael Fross]

I believe the general thinking is that A2 is harder to sharpen, but the edge lasts longer. Also, it's my understanding that it can't get quite as sharp as the O1.

That being said, I've always opted for the A2 over O1.

It probably does not matter too much, but I'm one of those guys who digs into details too much.



Michael

[Jeff Heil]

I have Veritas planes with both types of steel. I have noticed it takes longer to sharpen my medium shoulder plane with the A2 steel, but it holds an edge for a long time. My low angle block plane is O1 steel and I can get a very sharp edge with waterstones. Since I use it on end grain I thought it was a better choice. The reality is either type of steel or plane from Veritas will serve you well in my opinion.

Jeff

[Dave Anderson NH]

What follows is my opinion only Bob.

O-1 steel is perfectly adequate for use as a blade on a plane and most folks will find it easier to sharpen no matter what sharpening system they use. The ease of sharpening is due to slightly softer carbides in the metal matrix and the fact that it has a slightly finer grain structure. A-2 on the other hand is tougher, more wear resistant, and a good sharpening lasts longer. The difficulty with A-2 occurs because some sharpening systems don't work as well at the higher Rockwell hardnesses because of the harder carbides which impart the toughness to the steel. A-2 can be sharpened just as sharply as O-1 by a skilled sharpener with decently developed skills, but it is harder to deal with for the beginner. As for cryo treatment, the jury is still out and various different vendors will have different attitudes on whether or not it helps. The primary benefit of cryo is that it cuts the time it takes for the steel to develop its full hardness. More specifically, a new non-cryo blade which has been not been optimally controlled during the heat treating can take months before it reaches its full toughness while cryo can cut the time to that required to do the treatment.

[Mark Sweigart]

I'll add one other comment (note that I have no experience with this). The A2 blades, at low bevel angles, have a tendency to chip or crumble, from my understanding. Many people with A2 chisels need to increase the bevel angle. So, for a 38* blade, A2 will probably not be a problem (O1 is fine too). Now for the 25* blade, the O1 is probably the better choice.

mark

[Chuck Nickerson]

Recent sudies posted on another board show that A2 steel holds an edge much better if the bevel is > 32 degrees. So a 38 degree bevel seems well suited to A2 steel.

[Bob Johnson2]

Thanks All, that's wha6t I needed to know, and then some.