Perfect Pitch: The No. 4 Way to Reduce Tear-out

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

About Lost Art Press

Publisher of woodworking books and videos specializing in hand tool techniques.
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11 Responses to Perfect Pitch: The No. 4 Way to Reduce Tear-out

  1. dave brown says:

    re: high angles of attack etc for tear-out

    Ok, I’m on my second white-Jamaican (a white Russian made w/ coconut rum), it’s been a long week and I’m ready to pontificate.

    I tried the bevel-up-plane thing for a while (a year and a half) and it definitely works but dealing with steep bevel angles on a bevel up plane is a lot like dealing w/ any other high maintenance relationship — it takes a lot of work. I got tired of remembering which blades were honed at what bevel and trying to match the bevel the next time I honed and then swearing because the permanent marker had worn off the back of the blade. Also, high bevel angles degrade a lot quicker than than lower angle bevels. I got tired of being frustrated by honing — a very simple task.

    So, now I hone all my blades to 30 degrees on my 1000 grit stone and hone a three degree micro bevel w/ my 8000 grit stone. If I sense tear-out, I make sure my blade is fresh and taking a thin shaving. If that doesn’t help and I’m still getting tear out, I pull out my card scrapers or one of my scraper planes.

    If my card scrapers or scraper planes can’t deal w/ the wood then I toss out some curse words & grab my random orbit sander. 😉

  2. Dave,

    That is why this is the No. 4 way to deal with tear-out. The first three are (in my opinion) better strategies.

    High-angle relationships are high-maintenance relationships. But the rewards can be higher. Or you can lower your expectations.

    Why is this starting to read like a column about dating?

    Chris

  3. Tim Sproul says:

    When I first started using hand tools, I had some antique Stanley planes – the bailey line. I fidgeted with them a lot and got them to work on oak, maple, madrone, pine. Then I tried a 4 1/2 on some purpleheart. Oops. So I tried on some fiddleback hard maple. Oops again.

    Did a bunch of searching on the web and came across back bevels….so I tried that. If I went much more than a few degrees on the back bevel, it didn’t work. The iron would just chatter. But maybe that was because I was still using the standard irons. More likely, now with a bit more experience under my belt, is that I hadn’t fettled that smoother well enough. Anyways….it brings me to ask if back bevels work well independent of the iron. That is, if you have a standard very thin iron from an antique Bailey plane, will a back bevel perform? Or do you need an iron with more heft to it?

    And regarding the issue with tracking the angle on bevel up irons…..that’s what Sharpie markers are for. It is better to write the angle on the edge of the iron as writing on the flats is rubbed off as you sharpen. I also typically forgoe the jig and just use a stone…..one of the benefits of a thick iron is a larger bevel which makes freehand sharpening easier – but only easier if your stone cuts quickly. I do readily admit to getting the Veritas bevel up planes mostly to just have. I already had a ready supply of wooden Knight planes in different lengths and at bed angles from 45 to 60 degrees. Now the Veritas scraper plane is one whose primary purpose is NOT to fill shelf space, unlike the bevel ups….that plane is a true gem when my smoothers all seem to have lost their cojones!

    Tim

  4. Tim,

    Back bevels work with thin irons, even the laminated ones.

    I think the thick irons give you a margin of error on any handplane setup. With a thin iron, you have to have all the stars in alignment to get a thin shaving in a nasty wood. Your iron needs to be bedded really well. The cap iron can’t be bending the iron. The tension from the lever cap needs to be firm.

    With a thick iron, it reduces the propensity of the iron to chatter. And because the iron is thicker, the cap iron isn’t going to warp the iron. So getting that really thin shaving is easier all in all. This is not just true with aftermarket blades for Bailey-style planes, but with the thick irons on wooden-stock bench planes as well. Thicker is just better.

    Chris

  5. James Watriss says:

    So, here’s my big question, and this was an issue I saw bounced around at length on a message board, with responses from higher-profile folks like Larry Williams and Steve Knight…

    What’s your take on relief angles? IE, what’s the optimum angle behind the cutting edge, to allow for a clean shaving to occur? When it comes to low angle/bevel up stuff, the norm for what’s available seems to be around 12 degrees. But people like Karl Holtey (and others, whom I’ve forgotten) are actually making theirs with 22.5 degree bedding angles to increase the clearance angle. I know it’s possible to use a "standard angle" block plane to get something similar, and in theory that works very well as a smoother. I know some local luthiers who love them, and they’re particular about using the standard angle, too. (until they transition to japanese planes)

    Given that the re-beveling option is the same for either plane, do you think it’s a better idea to use a "normal" low angle plane, or a "standard" angle block plane for final smoothing?

  6. James,

    I don’t have a dog in that hunt.

    I have used both 12° and 20° bevel-up planes for smoothing, including three versions of Karl Holtey’s No. 98. Both planes leave a nice surface at a variety of angles on a variety of woods.

    I don’t see one taking a cleaner shaving than the other. Perhaps someone here on this blog can tell me what a clean shaving is. I’m not trying to be flip, I’m just not clear on the term.

    In hardwoods, I think a 10° clearance angle works fine. I’ve never had a bevel-up plane push out of a cut because of a clearance angle violation. I have done it with a bevel-down plane when I intentionally violated the clearance angle to see what happened (Note to self: get a life).

    As I mentioned above, the angle of attack is not something I get my panties in a wad about at the outset.

    Chris

  7. James Watriss says:

    I’m not really in the hunt either, but I’d heard such topics bandied about by other people who know much more than I do.

    What do you mean by "violate the clearance angle?" (I think I have some idea, but I’m still curious)

    I’m trying to stifle this ongoing plane obsession. My collection of old stanley smoothing planes has a habit of growing when I’m not paying attention. Someone snuck a Norris plane into my toolbox, too, and it’s made my Mathieson plane look pretty clunky by comparison. And my 50 degree L-N got me curious about their 55 degree frog. (If some high angle is good, than even more high angle is better?) In short, I’m trying to avoid any interventions re: my plane habit. But my mind seems to run in circles about the topic of planing finished surfaces. Surely the Lady of the Frog Pond will offer up the PERFECT PLANE one day. In the meantime, my obsession has resulted in nothing but more work when it comes to making sure that all of my tools are well tuned. Talk about needing a life.

    The low angle Jack has served me well for fine shavings and difficult smoothing tasks, as has the York pitch 4. But your post about taking thicker shavings got my wheels spinning again, and I’m wondering if a higher relief angle would make for more of a cutting action than scraping on the higher pitch stuff, and help make for a bit of an easier cut. Lacking real and actual [Information? Experience? Rational thought?] with regard to this particular question, I have no real way to satisfy my curiosity. So, it continues to burrow its way through my already too-short attention span.

    And now, I’m going to go drink coffee until my head spins, so that the voices in my head will quit their infernal yammering.

  8. James,

    The clearance angle is like religious esoterica. Only people who really talk about it need to know about it.

    If you honed an iron at 45° and put it in a 45° plane, it wouldn’t do much cutting. That’s because the clearance angle has been violated. When you cut wood with a plane, you compress the fibers down with the sole and cutter and then slice them. Then the fibers spring back a bit.

    If you violate the clearance angle — if the bevel is flat on the wood — then the fiber springback will push the cutter out of the cut. You won’t be able to make more than a very short cut and then the tool stops cutting.

    Few people ever encounter this problem. But it sure makes people sound smart who talk about it.

    For most woods, you need about 10° behind the iron to allow the fibers to spring back. Softwoods sometimes need a wee bit more (they compress more). Really hard woods need almost no clearance angle.

    Plane obsession is short-lived with most people. Then its chisel obsession. Then saw obsession. Then….. don’t know.

    Chris

  9. James Watriss says:

    I wasn’t sure how far you had to go to make such a thing happen.

    The plane obsession is pretty retarded at this point. Imagine a student at North Bennet going through plane after plane, surrounded by piles of irons and stones… "Nope, this one cuts perfectly, and I can see TV antennas reflected in the maple… Nope, this one cuts amazingly well, feels great in the hand… This one doesn’t seem right either, cuts curly maple without tearout. This one cuts shavings from oak that hang lightly in the air, that one managed to tame some problematic ribbon mahogany that had wind checking in other areas, this one… wow. Shiny."

    I’m not even sure what I’m looking for anymore. Maybe one that makes the surface ripple like water before settling into a glassy stillness that makes grown men cry.

  10. Michael Rogen says:

    Chris,

    Having had some major problems with tearout on some very innocent looking Mahogony, I needed some real help, real fast, so either I, (or was it you who reccommended it first)ordered myself a 50* blade for my Vertas low angle smoother. This put me at the magical 62* mark where in theory the nastiest looking woods as well as the innocent mahogony that was driving me toward a 55* frog for my LN 4 1/2, should be able to tame whatever is thrown in it’s path. I can report back that I still have some tearout and I’m going to take out the blade and put it back in the wrapper and box and make believe that I just received it and start over again.

    All together now James and Chris – "Get a life Michael" I have all intentions of doing that but first things first. I need to order that 55* frog from LN just in case that tearout rears it’s ugly head again.

    Michael

  11. James, Chris & Michael,

    I believe strongly that a 20 or 22.5 degree bedding angle makes much more sense for steep effective pitch, surface planing of cranky hardwoods, (in a bevel up plane).

    As someone mentioned, very steep honing angles are a right royal PITA.

    I have found it necessary to go to 70 degree EP for interlocked Santos Rosewood & Cocobolo & old growth Tasmanian Blackwood. I am quite sure this angle will deal with Michael’s Mahogany.

    At these extra steep EPs, a minute back bevel on a conventional bench plane, with a thick blade, is much less trouble to prepare and resharpen. I fear all these high angle frogs are a. too low & b. redundant in my workshop…….. Just one 60 degree frog might have some uses.

    That’s my take,

    best wishes,
    David BTW this is a great blog, has Chris been cloned several times? How can he possibly be write all this interesting stuff ??

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