Reading a plane's shavings

[Tony Caro]

I have read posts where hand plane users can tell a lot about how they're planing just by the quality of the shavings coming out. Is there a guide somewhere which elaborates on this? Just to clarify, if a shaving is curling up excessively, what does that tell you? If a shaving has parallel tear marks throughout it, what does that mean? If a shaving is thicker on one side than the other, it tells me that either the plane blade is favouring one side or I am pressing down hard on one side. Have seen where they can also tell if the plane blade needs honing, I usually decide that if I feel that the plane requires more effort to push through. Hope this makes sense.

[David Weaver]

Planes that need sharpening will leave a chip that's a little fuzzy (if they are really dull).

A shaving that's got a lot of cracks in it and curls up tight is just a chip that is breaking a little bit as it's cut.

A shaving that's close to straight with some waves has been broken close to the cut

AS far as lateral checks, it's more accurate to either sight down the plane or check the cut depth with a scrap on the corners.

[Tony Caro]

Thanks David, very helpful.

[Jim Koepke]

I watch the shaving for voids on one side or the other. They can indicate low spots.

Cutting ribbons often means the blade has a nick.

Not being able to take a fine shaving usually indicates a dull blade on a well tuned plane.

Here is something I wrote about 4 years ago:

http://www.sawmillcreek.org/showthre...anes&p=1512189

I have learned a bit since then, but it is still a good start.

jtk

[Tony Caro]

Thanks Jim, lots of useful info in that thread and others that I have seen from you.

[Jim Koepke]

Thanks Jim, lots of useful info in that thread and others that I have seen from you.

You are welcome.

If it helps, I am glad.

jtk

[Jim Matthews]

I'm late to this party.

I would say this about planing -
you're not always looking for a fine whisp of a shaving.

Sometimes (most of the time, really) - I'm trying to get to a given depth.

If I'm only slicing off 2 thousandths of an inch each pass, I'll never get to the end of a task.

Search cambered iron, reading grain direction and scrub plane.

FWIW - 80% of my planing tasks, from surface prep to jointing are with a #4 size plane.
It gets me VERY close to my dimensions, before I use another tool.
I consider my large jointer and smoother to be "finishing planes" to get the best final surface,
either for glue or finish.

One more thing - when you've got a really sharp blade, this is considerably easier as
the equipment becomes an extension of your intent.

If you haven't taken instruction on properly sharpening a plane iron and chisels,
it's money well spent. If there's a woodworking group near you, find someone
willing to show you a method (any method) that you can reproduce at home.

When I'm struggling with a planing step, I resharpen my blade.

[Sean Hughto]

Plane shaving reading is a highly personal and subjective process. Because abstract pattern recognition keys into our subconscious, self analysis produces the most relevant reading. One person may see an egg, while another sees a beetle in the same spot. Plane shaving reading is very much like a Rorschach (Ink Blot) Test. We are most likely to recognize symbols having a bearing on or connection with the matter at hand. Therefore, you are the most qualified person to read your own plane shavings.

[Sean Hughto]

Oh wait sorry, that was for tea leaves.

I have never found the need to "read" any plane shavings as such. I tend to read the surface being planed.

[David Weaver]

You mean you don't display the shavings when you're done?

I think the same thing - if the surface is good, I don't care too much about the shavings (though I do let the shavings tell me if I haven't set the double iron properly, or if it's moved when hammering the wedge or adjusting the plane).

It's somewhat unusual for me to get cherry from my local supplier that doesn't have some kind of problem (as in, it's never quite up to the snuff of being all downhill planing across the board). That's a function of them getting crappy wood from a commercial mill, though. Because of that, I always set a double iron and expect that on a very heavy shaving it will work the shaving....goes back to what jim said, I don't want to work thin shavings, and at the same time, I don't want tearout either.

So I guess I'd like to say I never pay attention to the shavings, but I just don't pay attention to the same things that the OP said.

Oh...and if I'm jointing a board, I expect the passes to produce a full width shaving. If they don't, either the board is tearing out somewhere or there's a low spot on the edge that I can't see from overhead.

Is this turning into a "I don't watch the shavings that much, only all the time?". I guess.

I don't expect anyone to do anything that I do, though. I keep reading posts on here that say the best way to deal with tearout is to sharpen the plane

[Sean Hughto]

I keep reading posts on here that say the best way to deal with tearout is to sharpen the plane

I haven't seen any of those posts.

But I do personally find that if I can only do one thing to achieve a better result in most any planing operation, the one thing I would pretty much always choose is sharpening the blade. I take it the one thing you would do is adjust the cap iron?

[David Weaver]

Yes, I'd learn to adjust the cap iron. It will avoid any problems with tearout once it's set properly, and the iron can be washita sharp or whatever sharp as long as there is clearance. It'll stay in the cut longer and you can take a heavier shaving.

I do back off for the last pass.

I like my planes sharp, though - especially in the sense that the geometry is right and the clearance is there.

It's my opinion that people who are woodworking should try to sharpen everything in the house that they can (scissors, utility knives, etc.... whatever), and then the whole sharpening thing is pretty trivial - it's just a matter of experience and hand eye (and not very much of it). It doesn't necessarily eliminate tearout, though, until you get to a shaving that doesn't have the strength to lift more of itself out of wood, and that's a really slow way to work or remove tearout that came from a penultimate step. But that's also the reason I questioned whether or not I should even provide advice several months ago, because we all like to make our own way for one, and for two, most people don't have a penultimate step - the penultimate step is a thickness planer, and if you remove those marks with a 1 thousandth shaving, it really doesn't present much of a hurdle.

To me, the time to sharpen is when you have to supply force to keep the plane in the cut. The double iron should do the rest, and give you freedom to do it as briskly and heavily as you'd like.

[Jim Koepke]

If you haven't taken instruction on properly sharpening a plane iron and chisels,
it's money well spent. If there's a woodworking group near you, find someone
willing to show you a method (any method) that you can reproduce at home.

Good advice here. It is amazing that once a single method (media) of sharpening is working how much easier all the other methods will be to learn.

jtk

[Tony Caro]

I'd like to say that I'm a beginner but I've been working with hand planes on and off for a few years. My sharpening technique has been refined over the years but no issues there, I can sharpen a plane blade to razor sharpness fairly easily. The intention of my post was to develop more of an understanding of the feedback that you can obtain by just watching things more carefully. Normally we don't pay much attention to shavings but some craftsmen are able to discern how a plane is working and whether it needs to be tweaked/sharpened just by its shavings. I'd love to develop a similar sort of awareness.

[David Weaver]

I don't think it's just an evaluation of shavings, though, it's an evaluation of the whole situation. How the plane is working, the surface it's leaving, the geometric results it's leaving, what the plane sound and feels like when it's working, and for certain things, what the shavings look like.