Another Question on David Charlesworth's Plane Technique

[Ray Bohn]

I just finished watching one of his DVDs; Part 2 Hand Planning. I am not sure that I am understanding his method of flattening a surface. By leaving a 1-2 thousands hollow in the middle, is he simply saying that this will insure that there will be no high spots to throw off the use of tools? If that is the reason, I think I get it. This technique is totally new to me and I wondered if I was missing something that would cause me to make huge mistakes as I tried to use it.

Thanks

[Chris Fournier]

Yes that is what he is saying. I like DC's early work but he is plowing a path towards ridiculous lately. Is a 1 to 2 thou hollow appropriate across 3", 8" 12"? How exactly do you measure this metal working tolerance?

Flatten your boards as best you can, and they can be flat - then move on.

[Jussi Auvinen]

Think about how tools and hand planes work and you will see the importance of a 'hollow'.
There is the reason why it is easier to flatten the cupped face (edges high) of a board, than a bowed (middle of the board high).
The plane will follow the bow but will ride the cup...Dont know if that makes any sense...


I think David explains this rather well in his videos&books.

[Chris Fournier]

Think about how tools and hand planes work and you will see the importance of a 'hollow'.
There is the reason why it is easier to flatten the cupped face (edges high) of a board, than a bowed (middle of the board high).
The plane will follow the bow but will ride the cup...Dont know if that makes any sense...


I think David explains this rather well in his videos&books.

I don't understtand this at all. You hold the plane, you take the cut, you evaluate the result on your way to flat. My handplane doesn't do anything that I don't want it to, it is my tool in my hands.I am not along for the ride, I'm driving.

[Jim Matthews]

If you cut a hollow in the edge, you can hear the plane stop cutting as it passes over the low spot.

Mine, when sharp enough make a whisking sound, like a broom on wet concrete.
When the sound is continuous, and you take a full length shaving, the edge should be flat.

Keeping it perpendicular to the face is matter of skill that still escapes me.

That's dealing with a surface no more than 1 inch wide.

Wider surfaces include more degrees of complexity.

*******

On planing faces, I was taught to find the cup in a board and have the "cupped side up" when flattening.
This requires wedges underneath the board to keep it from rocking.

The plane will register at the two highest points it passes, leaving a hollow in the middle.
When the shaving is the full width of the board, it's so flat as I can make it.
If the board isn't cupped, I just take a few passes off each side.

I don't do this with severely twisted or warped lumber - I don't have to use challenging material, and don't.

I'm not good enough with my planes to get the sort of precision described.
Mr. Charlesworth most certainly is.

If you've seen his furniture, you know he can do what he has described.

Consider it a goal to approach things this way, as your skill progresses,
your technique can be ever more refined.

For a hack like myself, I'm more worried about keeping things (relatively) flat and square.
That translates into smooth and functional.

Things don't fall off the table, and the drawers close.
That's enough for me, for now.

[Jussi Auvinen]

I don't understtand this at all. You hold the plane, you take the cut, you evaluate the result on your way to flat. My handplane doesn't do anything that I don't want it to, it is my tool in my hands.I am not along for the ride, I'm driving.


If thats the case then stop watching those videos, thats what you're missing :D

[david charlesworth]

Ray,

We have three possibilities for our surfaces and edges. Perfectly flat, minutely hollow or minutely bumpy. Flat would be nice if we could get it! Bumps are a menace for many reasons. One important one is that a set square stock will rock between two readings if it sits on a bump.

Therefore I prefer a minute hollow every time.

I tried to explain how useful a long plane and a slight hollow are in the other thread.

Any shortish surface or edge planed for long enough, will revert to a small bump. This is why stop shavings (hollowing) are so useful.

Best wishes,
David Charlesworth

[Ray Bohn]

Ray,

We have three possibilities for our surfaces and edges. Perfectly flat, minutely hollow or minutely bumpy. Flat would be nice if we could get it! Bumps are a menace for many reasons. One important one is that a set square stock will rock between two readings if it sits on a bump.

Therefore I prefer a minute hollow every time.

I tried to explain how useful a long plane and a slight hollow are in the other thread.

Any shortish surface or edge planed for long enough, will revert to a small bump. This is why stop shavings (hollowing) are so useful.

Best wishes,
David Charlesworth

"Any shortish surface or edge planed for long enough, will revert to a small bump."

Thanks, this explanation really helps me with understanding what has been happening to some of my work. The more I plane the worse it seems to get sometimes. Now your instructions on the DVD make sense and thank you for responding personally to my post.

Ray