Bevel Angles For 2 Small Planes?

[Allan Speers]

Hey folks.

I'm in the process of refurbing a bunch of planes that I've had in deep storage for years. Two of them have me stumped as far as bed angle and what bevel to grind. The blades are badly rounded, so no clue there, and I can't find any info online. Just cheapo little giys, but why not do them right? So:

----------

Stanley 100 squirrel tail:
The mouth is so wide, I'm not even sure if it's bevel up or bevel down, but I THINK it's BU, yes? I also can't quite tell what the bed angle is. It seems quite a bit steeper than your typical LA block plane. The Stanley 18 has a 20º bed and thus a 25º bevel, but this #100 is much closer to 45º.

So then it would HAVE to be bevel down, yes? But the blade is even thinner than a Stanley #5 iron, so if this is a 45º, bevel down design, should I grind a steeper bevel (maybe 30º) for more strength, or does that defeat the whole idea of a small, delicate tool?

----------

Stanley 102 Knucklecap:
This seems to be a typical BU block plane type, but I want to be sure. It looks to my eye a little steeper than 12º, but not by much & it's really hard to tell. Should I assume it IS 12º & grind it like a 60 1/2, or is it more like 20º?

[Jim Ritter]

Hi Allen,
if you look at the blade for the squirrel tail the side with the name goes up. I believe mine are all bevel down and I sharpen them at 25° and usually put a micro bevel on that.
I think you are right on the knuckle cap, and again any name or logo is on top.
jim

[lowell holmes]

At the suggestion of Rob Lee, I put a small back bevel on my apron plane. It works really well. The front bevel is 25 degrees (I think, I never measured it).

[Allan Speers]

Hi Allen,
if you look at the blade for the squirrel tail the side with the name goes up. I believe mine are all bevel down and I sharpen them at 25° and usually put a micro bevel on that.
I think you are right on the knuckle cap, and again any name or logo is on top.
jim

Ah, of course. Then the #100 is bevel down after all, and the bed is indeed 45º.

Thanks.

[Allan Speers]

At the suggestion of Rob Lee, I put a small back bevel on my apron plane. It works really well. The front bevel is 25 degrees (I think, I never measured it).

Lowell, are you talking about the Veritas Apron Plane? If so, that's interesting, but since I now realize that my #100 is bevel-down, I don't want to make the cutting angle any steeper.

================================================== ===

My one question remains, regarding the #100 with it's 45º bed and bevel-down blade:
Due to the extreme thinness of this blade, should I grind a steeper Bevel? I've never understood why 25º is the standard, and how relief / clearance under the blade matters.

- Also if a steeper grind affects how the easily the blade cuts. A plane isn't exactly a chisel, but wouldn't a steeper grind cause more resistance when planing?

If I end up liking and using this plane, I'll probably get a LN or Veritas blade for it, which will solve that problem and also tighten up the mouth a little, but for now .....

[lowell holmes]

[QUOTE=Allan Speers;2477724]Lowell, are you talking about the Veritas Apron Plane? If so, that's interesting, but since I now realize that my #100 is bevel-down, I don't want to make the cutting angle any steeper.

It is indeed the apron plane. A back bevel would not be appropriate. I have other block planes, but being bevel down, my comments would not be of value. I don't use back bevel on the other planes except for my LN 60 1/2. I do give it about 3 strokes of micro bevel.

[Jim Koepke]

Ah, of course. Then the #100 is bevel down after all, and so the bed is indeed 45º.

Thanks.

Why 25º became the 'standard' angle of grind is not known by me.

With a bevel down plane less than 25º tends to chatter. At much more than 35º the relief clearance is lost and the plane starts to skip over a surface.

Grinding the thin blade on the #100 to 30º would be fine for use without causing any more effort in use. It may actually make the cutting edge last a little longer.

jtk

[Allan Speers]

Thanks, Jim.