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This Year’s Model: The 2008 Sawbench

Posted on by Lost Art Press

I end up giving away all of the sawbenches I build to woodworkers who give me those wet, doe-eye looks that say, “I don’t think I can build one.” That’s ridiculous, of course, because these things are as easy to make as a box of brownies. But I’m soft, I suppose, like the resulting brownies (always undercooked, natch).

The downside to my sawbench charity is that sometimes I end up without any sawbenches in my shops, which makes me nuttier than squirrel poo. The upside, is that I get to make more sawbenches, and each generation gets a little better.

This weekend I built the sawbench that me and my students will be building during my handsawing classes in 2008. This example can be built from one 2 x 8 x 10’, and it took me about four hours to do – I machined all the stock flat and cut all the joints by hand.

This sawbench is a little different than the others because it’s designed to be a hand-sawing exercise. All the joints are entirely saw-cut. No boring. No mortising. No chopping.

Now if you’ve gotten to this point in the blog entry and are wondering “What in Moxon’s name is a sawbench?” then check out this old entry on my blog at Woodworking Magazine. Sawbenches are magical devices that make full-size handsaws really work (handsaws stink at bench-height, except for overhand ripping). Plus, I assemble carcases on them, use them as stepstools, plane table bases against the sawbench’s bird’s mouth, and eat my lunch while sitting on one.

I don’t have construction drawings drafted for this bench yet, but you don’t really need them. Here are the basics: Make the bench about knee-high. This one is 19-3/4” high. The legs are angled 10° off 90°. The legs are notched at the top at 10° to fit into mating notches in the top. All the stretchers are attached to the legs with half-lap joints. Glue and screws keep everything together.

Here’s my materials list:

1 Top 1-1/4” x 6-3/4” x 32”
4 Legs 1-1/4” x 2-1/2” x 21”
2 Long Stretchers 1-1/4” x 2-1/2” x 26”
2 Short stretchers 1-1/4” x 2-1/2” x 12”

The only slightly tricky thing is cutting the feet so the sawbench sits flat on the floor. This is great fun to do once you know the trick. First put the sawbench on a flat and level surface. Then take small wooden shims and shim under all the feet until the sawbench is level on both its length and width.

Then take a small block of wood and cut an 11° bevel on one edge. Place this on your known flat surface and use the block to mark all around the legs of the sawbench (the beveled end allows you to make the outside angle of the legs).

Then clamp the sucker to your bench and saw the feet to your lines. This might seem hard. It’s not.

As always, I plan on keeping this sawbench until I retire. But that’s not likely to happen. Plus, I need to build another version that uses lapped-dovetails for one of the advanced classes I’m teaching in July.

— Christopher Schwarz

Skewing: The No. 7 Way to Reduce Tear-out

Posted on by Lost Art Press

I keep a short list in my head of what I like to call “The Woodworking Mysteries” – things that I pretend to understand but are really just outside my grasp.

One of the mysteries is how a tree can pump water and nutrients from its deepest roots to the furthest reaches of its branches. We have many clues as to how it works, but a complete picture eludes me at least. Another mystery is about how yellow glue (polyvinyl acetate) actually works. Again, I’ve never read a satisfying explanation.

A third mystery relates to handplanes and basic geometry. One common strategy for reducing tear-out in a board is to skew the plane as you make the cut. This strategy was beaten into my head by all my teachers dead and living. It’s repeated on the Internet by people I deeply respect and trust. And I do it myself in my work.

But if you do the math, you will quickly see how this strategy doesn’t make much sense on its face.

Let’s start with a fact that we do know: The higher the angle of attack when you plane a board, the less likely you are to experience tear-out. This is an almost immutable truth. It’s why we have high-pitch planes and scrapers in our arsenals.

Now for another fact: Skewing a plane in use reduces your angle of attack. Mike Dunbar, the founder of The Windsor Institute and a personal hero, explained this to me in the clearest way possible. When a shaving encounters a plane iron, the angle of attack is like a hill that the shaving has to walk up. If you walk straight up that 45° hill, that’s a lot of work. When you skew the tool, it’s like the shaving is walking up the hill at a lower angle. Or put another way, it’s a bit like building a road up a steep mountain. You don’t make the road go straight up the mountain, you build switchbacks so the vehicles can actually make it up the incline. Skewing reduces the amount of work required – both to plane a board and to climb a hill.

How much does skewing reduce your angle of attack? John Economaki, the founder of Bridge City Tools, published a brilliant chart that explains this on his web site page that promotes his variable-pitch plane. You can see the chart in full here (scroll down to the section titled “Skewing the Plane.”) You can look at this chart and see immediately that skewing a 45°-pitch handplane by 30° will reduce your effective angle of attack to 40.9°.

So here’s the problem: If high planing angles reduce tear-out, and skewing a plane reduces your angle of attack, then how can skewing the plane reduce tear-out?

Here’s a hint: The answer is in the branches.

Planing with no skew resulted in no tear-out on this ash board.

To explore this seeming contradiction, I did a little experiment in the shop on Saturday. I took a short piece of ash with pronounced grain direction – that is, there was no question about which way the grain was traveling in the board.

I cleaned up one face with a smoothing plane and then turned the board around so that I planed against the grain, which is when you are more likely to encounter tear-out. Then I planed the board with a bevel-up block plane, the Lie-Nielsen 102. This plane is bedded at 12° and the iron is sharpened with a 35° micro-bevel, so its angle of attack is 47°. The mouth on the plane is wide open, so it’s not much of a factor. The tool is set to take a shaving that is about .002” thick.

Planing with a 30° skew created this ugly patch of torn grain.

First I planed the board against the grain without skewing the tool. This cleaned up the board just fine with no tear-out. Then I skewed the tool by 30° (which lowered my effective planing angle to about 43°) and did the same operation. I tried skewing both to the left and to the right. Two areas of the board tore out grotesquely.

Then I cleaned up the board again and tried skewing the plane at 20°. Tear-out occurred at the same two places but not as badly. So I tried skewing the plane at a variety of angles. And without fail, the more I skewed the plane, the more tear-out occurred.

So how can skewing reduce tear-out?

You have to remember that trees are not manufactured items. They are giant cones made of fibers that grow in different directions as the tree responds to its environment: a hill, a disease, a wind storm. Then we slice them up into shapes suitable for building things, regardless of how the fibers are traveling through the tree.

In some boards, grain can change directions on you a couple times. And the grain can be at odd angles – you cannot assume that all your boards will have grain running from one end to the other – the grain may be traveling at a 20° direction along the face of the board and 10° along the edge. And the grain might be in the shape of a shallow wave.

So there are times when skewing the plane puts the edge in the right position at the right time to deal with that patch of grain.

Planing at a 20° skew created a little tear-out.

In my example board above, the two places where the tear-out occurred were at places where the grain rose quickly. So how did I deal with this board? As I encountered the areas that tore out, I straightened out the tool – no skew. When I worked the areas that didn’t tear out, I skewed the tool to reduce the effort required for planing.

So the trick with skewing takes us back to the No. 1 way to reduce tear-out: The best strategy is to select the best woods possible and learn how to read the grain so you can begin to predict how your tools will behave. Sometimes, the best strategy is to not skew the tool.

Or put another way: Because grain is irregular, sometimes skewing the plane allows the blade to encounter the grain at a non-skewed angle – and to therefore plane it without tear-out.

This is the end of my series on planing. I hope that some part of it was helpful. Next week, we’ll probably return to the topic of (surprise!) workbenches.

— Christopher Schwarz

What Wood Would Be Good? (What Wood Wouldn’t?)

Posted on by Lost Art Press

Whenever a beginning bench-builder bends my ear, the No. 1 question they have is usually about what species of wood they should use to build their workbench.

They’re almost always vapor-locked on the issue and unable to proceed on their design until they pick the perfect species.

In my experience, there is a far better way to ask this question: What woods shouldn’t you use to build a bench? That list is far shorter.

Depending on your workbench’s design, the list of verboten species could be entirely empty. You can make a fantastic workbench out of the cheapest white pine 2 x 12s at the home center – just make the top 5” thick and the legs 5” x 5”. It’ll be awesome.

But people don’t want to use white pine I guess, because that’s for stud walls and skateboard ramps. Or it’s too cheap. Or it dents too easily. So I know that I can’t talk anyone into making a white pine bench, no matter how hard I try.

So here’s are the important characteristics of an ideal workbench wood that won’t get you laughed out of your local woodworking guild.

1. It should be stiff. A stiff species will allow you to cross long spans with the top unsupported by aprons or braces, which can get in the way of your clamps. To determine how stiff a species is, check out the chart I’ve included here that I lifted from my book, “Workbenches: From Design & Theory to Construction & Use.” (It’s fun to violate my own copyright.)

2. It should be heavy. Heavy benches are superior to lightweight benches, which you chase around your shop. A heavy bench moves only when you want it to. Check the wood’s specific gravity – its weight compared to water. That’s the measuring stick for this characteristic.

3. It should be inexpensive. You don’t have to buy steamed European beech to make a great bench. Until recently, European beech was expensive in this country (prices are falling). European cabinetmakers chose beech for their benches because it was stiff, heavy and cheap.

4. It should be readily available. Workbenches are great. The only thing greater than a workbench is all the great stuff you get to build on it. Don’t delay building a bench because you’re having trouble finding the wood.

5. It should resist denting. This is a bit of a minor point because I’ve worked on benches that dent easily. And it’s no big deal when they get dented because it won’t affect the quality of your finished work and you eventually work the dents out when flattening the top. To determine how dent-resistant a species is, check out its Janka scale rating.

6. It should be light in color. I wouldn’t enjoy working on an ebony bench. It would be really hard to see what I was working on. You’re often sighting things against your bench, such as when you peer down your plane’s sole to see if the iron is centered in the mouth. A light-colored bench makes this easy. Plus, the benchtop reflects light, making the shop appear lighter.

7. It should be easy to work and glue. Purpleheart and hickory get used to build masochist workbenches. You’re going to have to flatten the top of your bench some day, so make it easy on yourself, long-term.

So what woods excel in many of these categories? Plenty. In my neck of the woods, yellow pine, ash, white oak and red maple would all be outstanding low-dollar benches. (Especially ash. Thanks to the emerald as borer, ash is about as cheap as yellow pine these days.) Oh, and don’t be afraid to mix species. If you’re short on cash, make your base from a junk species and spend the money on the top. You can always replace the base.

Here are some other choices. A little pricer but still solid: white oak, white maple, birch and beech.

OK, but not my first choice: poplar, red oak, hickory (too hard to work).

Probably not, except in a pinch: walnut, cherry (too dark and a little soft), basswood (too soft), sycamore (too hard to work the quartersawn faces), and almost all the exotics (too expensive and sometimes difficult to glue).

So if the question about wood species is a red herring for bench builders, what do I think is the most important question about bench design? Here it is: How soon can you start building?

— Christopher Schwarz

Gluebeard

Posted on by Lost Art Press

In high school I played racquetball every day — sometimes for four or five hours a at a time. But the funny thing was, no matter how much I played, I never got any better unless I was matched against someone who could crush me.

So I would always seek out friends and acquaintances who could wax the floor with me and my little white sweatbands. After playing them for a few weeks (or months), I would edge up on them gradually and (with patience) eventually beat them.

It turned out to be an excellent lesson for woodworking.

When I build and when I write, I’m happiest when I am working at the limits of my skill. Every project and every piece of writing should have some detail or structure that is tricky to execute. If I’m not improving, I’m rotting.

So it is with great trepidation when I build a project for Popular Woodworking’s “I Can Do That Column.” On the one hand, these projects aren’t improving my skills much. They are the simplest joints (glue and nails, generally) and the level of design is generally Shaker, Arts & Crafts or some other straight-line style.

On the other hand, I enjoy the heck out of building these projects. The Pleasant Hill Firewood Box shown here took me about five hours to build all told, from making the first crosscut on a miter saw to rounding over the lid of the kindling box with a block plane.

This weekend I began applying the finish to the piece and I tried to sort out some of this stuff. On the one hand, the project seemed like a waste. As I was building it, I was trying to explain why the column was so important to a couple of readers who came for a visit. That you need to give beginners a way to get started in the craft without forcing them to build a highboy out of the starting gate.

As I was explaining all this, I was getting a look from the readers. Either they were indifferent (they both do very high levels of work) or they were disappointed in me. I felt like I was rotting a bit.

But then something else happened. On Saturday I spent three hours finishing up the construction. I nailed the back and front in place (wood movement be darned). I added the hinged lid (it took 10 minutes to fit it perfectly the first time). And I detailed the carcase with a block plane, softening lines and making this reproduction look as much like the original as I could. In the end, every joint was to my satisfaction. And the lid fit like a glove.

As I drove home Saturday I felt something weird stuck in my beard. It was sizable, hard and stuck firmly. After some digging (and yelping like a little girl at one point), I pulled out a nugget of dried yellow glue that had obviously been stuck there for several hours without my noticing.

There, I thought, that was the point of the day. I had gotten so lost in the project that I hadn’t noticed putting a dime-sized drop of glue in my own beard for several hours. Yet, despite my inattention, I had built this project in record speed and with great precision.

I had learned something I couldn’t quite my finger on. I flicked the dried glue to the floor of my car and turned my attention to the road ahead.

— Christopher Schwarz