A2 for Low Angle Block Plane

[Bryce Adams]

I'm looking to buy a new Hock blade to upgrade my Stanley 60 1/2 low angle block plane. My plan is to have a blade ground at 25 degrees for 37 degree low angle work, and a second blade ground at 38 degrees for 50 degree high angle work.

I've read a fair amount that A2 shouldn't be ground at less than 30 degrees because of edge brittleness. Would it make sense to use O1 for the 25 degree blade and A2 for the higher angle?

[Sam Takeuchi]

You'll be fine with 25 degrees. I have that blade ground at 25, and never ever had a problem.

[Chris Kennedy]

I think Lee Valley regularly grinds their A2 blades to 25 degrees all the time. All of my planes are A2 steel with most at 25 degrees without complication.

Cheers,

Chris

[Shawn Patel]

Their Low angle Jack plane ships with a 25 deg bevel in your choice of A2 or O1. They give no caveat that the A2 is somehow weaker.

For the definitive answer, you might call them. They've been exceptionally friendly, honest, and helpful to me.

[Eddie Darby]

O-1 will sharpen to a sharper edge than A2, and the end-grain cutting action benefits from a nice sharp blade, so I would go with O-1 in this case, and do the more frequent sharpening.

I see that LN are now offing O-1 blades for planes now.

A2 retains it's edge much better at angles above 30 degrees.

[Bryce Adams]

I exchanged emails with Ron Hock today, and he said that A2 is, indeed, more brittle than O1, but it wouldn't be a problem with a 25 degree bevel in a block plane. In fact, he recommended it.

In a chisel, that takes a lot more punishment, he said that higher bevel angles help strengthen the edge.

I'm going to buy the A2 blade.

[Pedro Reyes]

I have A2 on most of my block planes, some Hock A2 some Lie Nielsen A2. And while I've heard that O1 does get sharper, A2 gets plenty sharp (shave hair effortless) and since endgrain does punish the edge, I think A2 was the right choice for me. just my 2.

/p