One of the most common errors when planing is to create a gentle banana shape on one face – where the ends of the board end up thinner than the middle.
The cause of this problem resides both in you and in your tool. First off, divide the sole of your plane into two regions: The infeed side of the sole before the blade (the toe). And the outfeed side of the sole behind the blade (the heel). And remember this: The blade of your plane isn’t co-planar with the outfeed side of your handplane.
This feature makes it different than your power jointer. As a result, a handplane has more of a tendency to make bananas. (By the way, you can make bananas – and wedges – with a power jointer as well).
But I think the tool’s role in banana-making is a minor problem. The bigger problem is you and where you are putting pressure on the tool as you plane. Here’s how it’s supposed to work:
At the beginning of the cut, plant the toe of your tool firmly against the work. With the hand on the front knob, put all of your downward pressure right there. Your other hand (on the tote) should only push the tool forward.
As soon as the entire sole is on the work, you should shift your pressure: Use equal and forceful downward pressure with both of your hands.
As soon as the toe runs off the end of the board, release the pressure there but continue to exert downward and forward pressure at the tote.
This work, but it can be a trick to remember for beginning planers. It’s hard to get all your muscles lined up. So I tell them this simple mental trick: Just try your darndest to plane a big old hollow valley in each board by scooping out the middle.
Planing a hollow in this manner is almost impossible to do with a handplane that has a flat sole. So what you wind up with is a board that is fairly consistent in its thickness.
I cannot take credit for this mental trick, but I can’t remember who told it to me years ago. But works like crazy. And with that aspect of planing under control, you can then turn your attention to removing cupping and twisting in your boards.
— Christopher Schwarz
Chris,
I read that trick somewhere – AND I thought it was you who published it *somewhere*, a long time ago. It sure came in handy when I flattened my Sjobergs workbench a few weeks ago. In case you don’t remember the details of our conversation, you can find the post at: http://sandal-woodsblog.com/2008/05/20/episode-11-flattening-the-workbench/ . There is NO way I could have this any other way, except by starting it, and then continuing. In other words, once started, there was NO going back.
And to make sure I *would* prevent bananas, or any other shape, I used winding sticks. The video shows the entire thing, compressed in several spots, to minimize viewer boredom. But it turned out perfectly flat – so good, in fact, that I think I will be using it for assembly, too.
Darnit! Just when I thought I had a handle on this flattening-with-a-hand-plane thing. I did quite a bit of it on my last project with my old Bailey #7. But when I read, "The blade of your plane isn’t co-planar with the outfeed side of your handplane" my overly-cultivated left-brain started trying to picture how I flatten anything with that configuration, and now I’m confused all over again.
This just goes to show (me) the value of trying and doing this stuff and the problems over-thinking it can cause.
Chris,
I remember seeing your video and you mentioned the trick of just tyring to "scoop out the middle!" I have used that trick to explain to others whom are just learning how to use a handplane!
There is no simpler way of explaining how to use a plane and seeing the postive results from the explanation!
One of the things that I picked up from reading Peter Galbert’s blog was a good tip for working on planing technique. The trick, of all things, is not actually to do any planing, per se. Get a fairly narrow board (say 2 in. square, long enough to clamp somewhere fairly easily), back off the iron, then work on making your plane ride over the end of the board and keep it level. I don’t pretend to be any kind of good at it, but this seemed to me to be a great technique builder. Yours does too, of course, and I will use it, as well. Anything can only help me; I have been drowning in bananas, it seems like.
Thanks for dusting off another overlooked tidbit of planecraft. I’ve been doing what you describe for years. And you are correct that it becomes a job of muscle memory and is best learned early as opposed to attempting to reset old habits.
Sometimes on SYP I end up with the board a shave or two "thicker" at the ends. So when I take those last two full length strokes, I keep the weight of my hand on the knob as it leaves the board and viola! C’est facile, non?
A’ bientot, mon ami.
always,
J.C.
As you push a plane along a board, the wood behind the cut will be below the level of the wood in front of the cut. Only the sole in front of the cut can ride on the wood. Therefore, you should keep gentle pressure on the knob of the plane.