After taking a recent course in handwork, Rick Gayle, a reader and professional painter, visited our shop at the magazine this fall and looked over some of the planes in my wall-hung toolbox. He reached up to one of the cubbyholes and pulled out the Veritas Bevel-Up Smoother Plane.
“This plane,” Rick said, “has made all other planes obsolete. Well, that’s what my instructor said.”
It’s a strong statement to say that hundreds of years of handplane manufacturing have now been eclipsed by one tool, but I know what Rick’s instructor was getting at. When it comes to reducing tear-out, one of the most important weapons you have is the angle of the tool’s cutter – aka the “angle of attack.” And no other tool gets you to that optimal planing angle as easily as that style of tool.
The higher the angle of attack, the less likely the wood fibers will lift up and tear out. Sounds good, right? So what’s the catch?
The only practical downside to a high angle of attack is that the tool is harder to push. And that’s not much of a factor when your shavings are so teeny (see the No. 3 way to reduce tear-out for details on teeny shavings). Plus, the high angle of attack works great with well-behaved hardwoods, too.
In basic terms, this is why card scrapers, cabinet scrapers and scraper planes are the last word in battling tear-out. Scrapers cut at a very high angle – in fact the angle is so high that they actually cut the wood in a different manner and the resulting surface of the wood looks a bit different.
So what does the Veritas plane have to do with the angle of attack? After all, its cutter seems slung a lot lower than the cutter on a traditional plane. Well, the difference is that the Veritas (and some other block-plane-like tools such as the Lie-Nielsen No. 164) work with the cutter’s bevel facing up, while traditional planes cut with the bevel facing down.
This makes a huge difference.
In a traditional plane with the bevel facing down, the angle of attack is almost always set by the frog (the casting that holds the cutter). In almost all vintage metal planes, this angle is 45° (new planes by Lie-Nielsen let you pick a 50° or 55° frog, however).
When you flip the cutter over, the angle the bevel is sharpened at comes into the equation when figuring out the angle of attack. Here’s how: The cutter in a bevel-up plane is usually bedded at 12° or 20° to the sole of the plane. Let’s use 12° for our example. So if you sharpen the cutter so it has a 30° microbevel on it, then you add the angle of the bed (12°) to the angle sharpened on your cutter (30°) to get the angle of attack (42°).
So this configuration would make a bevel-up plane behave much like a traditional bevel-down plane – or perhaps even a bit worse.
But if you sharpen the cutter at 45°, instead of 30°, then the world changes. You add the 45° to the 12° and suddenly you have an angle of attack that is 57° – that’s fairly steep. And you can achieve it (and remove it) with just one quick sharpening.
So what’s the best angle of attack for gnarly woods? I’ve found that with almost all woods, tear-out tends to disappear with a 62° angle of attack – that means sharpening a 50° bevel on your cutter and putting it on a 12° bed in our example.
So is Rick’s teacher correct? Should I melt down all my other planes?
Back Bevels: Easier than You Think
Before you fire up the smelter in your basement, consider this: You can achieve high planing angles with a traditional plane (old or new) by sharpening a shallow bevel on the unbeveled face of the cutter. This, in essence, turns the bevel-down tool into a bevel-up tool.
The math is the same: Say your iron is bedded at 45°. If you sharpen a shallow 12° bevel on the usually unbeveled face, then you will have achieved the same 57° angle of attack as you did with a bevel-up smoothing plane.
Back bevels scare many woodworkers. But once you do it, you’ll wonder what the big deal was. To hone a back bevel, I use the same cheap honing guide I use for the primary bevel. First I sharpen the primary bevel as per usual. Then I flip the iron over and set it back in the jig as shown in the photo.
I have a piece of wood with some shallow angles drawn on it: 10°, 15° and 20°. I line the iron up with the desired angle and then take the tool to the sharpening stones and hone a small bevel using my #1,000-, #4,000- and #8,000-grit stones. You don’t need much, less than 10 strokes on each waterstone does the trick for me. (Don’t forget to put a little pressure on the corners of the iron as you sharpen so that the cutting edge keeps its curved shape.)
Then I set the cutter in the plane as per usual and go to work. With a sharp iron, thin shaving and high angle of attack, tear-out usually recedes quickly – like Joseph Biden’s hairline.
But when it doesn’t, I turn to the strategy I’ll detail next week. Here’s a hint for the “Wives Against Schwarz:” None of the strategies in this series will be “Buy a Holtey.”
— Christopher Schwarz
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