Using a straightedge is easy, right? Yes, but it does pay to use a technique that is both practical and consistent with the tolerance to which want to work.

Pictured above are, from front to back, a 6″ Bridge City rule, the 18″ beveled Starrett #385, the 24″ unbeveled Starrett #380, and a Lee Valley 50″ aluminum straightedge. The photo below shows the thicknesses, from left to right, of the 6″ rule, a Starrett combination square blade, the #385, and the #380. The Lee Valley is about 7/16″ thick at its base. 

Let’s look at three techniques for using a straightedge and consider some of the related features of different straightedges.

1. Eyes won’t lie

This is the way a straightedge is usually thought to be used. You simply hold the tool against the surface and look for gaps against a light. Done properly, this allows the eye to easily detect gaps of 0.0005″ (half a thou) or less.

It is helpful to use a diffuse, linear background light, such as a fluorescent bulb, and a thin edge against the work, such as a beveled edge. If a wider edge is used, ensure that your line of sight is parallel to the surface. A false impression of accuracy will result if the light under a gap is blocked from view simply because there is an angle between your line of sight and the width of the tool’s edge.

This technique can be awkward and tiring because you have to hold the tool and the work up to the light, or bend and maneuver to view a stationary surface. It is good for testing a plane sole or other small, very precise work. The #385 or an accurate small rule are good choices. Avoid tipping the straightedge which can introduce errors caused by any slight bow of the tool along the length of its face.

2. Shim it, shim it again

Here you lay the straightedge on the surface and use feeler gauges to seek out gaps. Look for hollows near the middle of the tool, but also press down near an end to check for gaps at the opposite end created by a bump somewhere in the middle.

A good way to work to a specific tolerance, say 0.001″ for a plane sole that you are lapping, is to put a leaf gauge under a wide-edged straightedge, and then gently pull the leaf to see if it drags the straightedge or slips through freely. The former indicates you are within tolerance (as long as there was no previous rocking of the straightedge), the later indicates a gap. Decide how large and where you can tolerate errors.

This technique is also handy to test a tablesaw top or jointer bed which you cannot lift and where bending is difficult or impossible to get your line of sight parallel to the surface.

The #380, or any tool with a similar wide edge, is a good choice for this technique.

3. Swing it easy

The first two techniques are slow and almost always overkill for wood preparation. So here’s the quick, easy, practical method that I suggest for dressing stock.

Set the straightedge on the wood, grasp and unweight one end, but do not lift it, and gently swing it along the surface. See where the tool “grips” or pivots. If it pivots just barely at the opposite end, the surface is slightly concave. If it pivots somewhere in the middle, you’ve got a bump. In woodworking, bumps are generally undesirable so you work with a one-sided tolerance, flat or a trace concave. You’ll quickly get the feel of this method.

Here is where a heavy, wide-edged, metal straightedge gives you a nice feel on the wood. The steel Starretts or the big Lee Valley aluminum work well.

This is convenient - no lifting or unclamping the work - and it quickly tells you what you want to know - that one-sided tolerance. It allows you to work in rhythm with your craftsman’s intuition.

In conclusion, the straightedge, while the simplest of tools, requires matching the technique to the task.

That title may make my spam-comment filter work overtime. Anyway, this post continues the discussion of managing figure in wood. Let’s look at the orientation of the annual rings in the rectangular blanks from which curved legs will be cut. Short sections of Douglas fir will be used to illustrate the principles.

All of this refers to legs which curve in three dimensions (planes). The curves may be cut on all four faces (e.g., a cabriole leg) or just two adjacent faces. Legs in which the curves are cut only on two opposite faces are curved in only two dimensions (picture the leg sandwiched between two flat sheets of plywood) and are a somewhat different matter. Bent lamination legs are an entirely different matter. Please do not ask me about legs which alter the time-space continuum.

The photo above shows the three possible basic orientations. The dot on the end grain indicates the inside corner of the legs. The two faces adjacent to this corner usually each have a flat portion where the aprons are attached with mortise and tenon joints.

In the three legs, from left to right, consider the endgrain patterns:

• The annual rings are approximately parallel to one face and perpendicular to the other, producing one flatsawn face and one quartered face.
• The annual rings are approximately 45° to all four faces and run “across” the inside corner.
• The annual rings are approximately 45° to all four faces but run parallel to an axis from the inside corner to the outside corner.

For simplicity, I cut the curves into two adjacent faces. The effects would be the same if curves were cut into all four faces such as in a cabriole leg.

Let’s look at the results.

The leg on the left is bad news. The irregular figure produced by cutting a curve into the flatsawn face is unpleasant in itself, and the inconsistent figure among the faces distracts from the shape of the leg.

The middle leg is an improvement but, to my eye, the figure lines fight the curves of the legs. There is too much run-on and run-out of the annual ring lines.

I like the leg on the right. By cutting the blank from approximately 45̊ riftsawn stock and orienting the growth rings in this way relative to the inside corner, a good lookin’ leg arises. The shape of the leg (though uninteresting in this example) coordinates with the figure.

Here are closer views: 

Note that another disadvantage of the leg on the left is the exaggerated consequence of a small knot intersecting the cut line. Small pin knots, such as are common in cherry, can be difficult to avoid, but the middle leg demonstrates that they will have much less consequence with that grain orientation.

It is hard to find a thick, purely riftsawn board from which to make leg blanks, but most fairly wide flatsawn boards contain some effectively riftsawn stock toward the sides. I examine the end grain and face grain and carefully select the best sections of such boards. I pay attention to the straightness of the figure along the length of the board, recutting the edge to “straighten” the figure lines if necessary. I also try to somewhat coordinate bends in the figure with bends in the leg design.

Of course, you can choose however you like to use figure, but the key is to be aware of it and manage it. Making your design and the beauty of the wood work together, each enhancing the other, can bring class, beauty, and quality to your woodworking projects.

Happy woodworking to you.

Wood has figure that was created from life, which, in turn, helps bring life to a creation in wood. Throughout designing a piece, choosing wood, and building, I want to make the most of what the wood has to offer so a synergy develops between the design and the wood. This is not aluminum, Corian, or clay upon which a design is imposed; this is wood!

When cutting curves in wood, it is helpful to predict how the figure will change. The figure should work with, not fight, the contours of the piece. The interpretation of that task is subjective but it pays to be aware of and work skillfully with the figure. (Bent lamination, by the way, is a different matter.)

Here is a visual guide to some of the issues that arise in curved work. I used home center Douglas fir which has obvious figure lines created by the large difference between the earlywood and latewood. This is for purpose of illustration, it is not meant to be pretty.

In the photo above and the next two below, a concave curve (marked on the top surface) cut into the rift face causes the figure to bend. The end grain is emphasized with pen lines to show that the annual ring lines go downward as you go deeper into the wood. Thus, the concave curve creates a smiley bend from the straight face. A convex curve would do the opposite. 

Below is the result if we started with the block with the opposite face on top. (I just turned the same block upside down.)

Now let’s cut a similar curve into a nearly-flat-sawn face. The end grain lines meet the face at an extreme angle and so the figure changes rapidly as we cut the depth of the curve. The result is, to my eye, unattractive. Some of the figure lines run off the resultant face at the bottom and jump on at the top.

Now let’s cut the curve into the quartered face. Since the annual ring lines meet the face at about 90̊, there is almost no shift in the direction of the figure after the curve is cut. 

Of course, many other variables come into play, including the depth and consistency of the curves, and their placement in the piece. None of this would matter much in basswood which is nearly absent in figure.

The main ideas:

• appreciate that the figure changes as curves are cut into wood
• it is helpful to be able to generally predict how the figure will change
• use this to the best advantage of the wood and the piece you are making.

Next, we’ll look at how this applies to curved legs. The appreciation of figure and legs, now there’s a worthwhile topic.

1. Be a control freak

Once a machine woodworking procedure starts, any unexpected event will occur suddenly, probably too quickly for you to react. At that point, your defense is whatever margins of safety, such as guards and hand clearances, that have been built into the setup and come into play after the mishap. You have to hope they are adequate to prevent injury.

The safest way to use a woodworking machine is to know, before starting, exactly what is about to happen. It should be a completely predictable operation. We know the machine itself will operate in a fully predictable manner (the blade or bit spins), and so your job is to thoroughly understand and control the interactions among you, the wood, and the machine. You must understand all the forces at work. In short, don’t hit the start switch if your mind harbors doubts!

Of course, still use the guards and clearances.

2. Cut or throw?

A machine blade or cutter, given the opportunity, will always throw the wood rather than cut it. You must deny the machine that opportunity by restricting the movement of the wood, and ensure that it has the capacity to cut the wood. Using hand-held power tools, it may be the tool itself, with your hands still holding it, that gets kicked.

All of the following mishaps, among many more, are essentially a cutter throwing the work piece because the operator gave the machine an alternative to cutting it:

• Table saw kickback - the absence of a splitter/riving knife allows the kerf to pinch the rising blade which grips and violently throws the wood.
• Thickness planer kickback - a short board is freed from the infeed roller before reaching the outfeed roller so the blades grab and eject the unrestricted wood.
• Drill press - the rim of a bit, such as a large diameter Forstner, snags an unclamped work piece and throws it, or worse, pulls in the hand that is trying to hold it. Re-entering a hole with a spinning bit increases the chance of this disaster.
• Bandsaw - wood held above the table surface is presented to a coarse tooth blade and gets slammed to the table, drawing the worker’s hands with it, possibly into the blade.
• Router table - uncontrolled climb cutting (feeding the work piece in the direction of the cutting edge rotation) zooms the wood across the table, possibly carrying the woodworker’s hands into the cutter.

Well, I’m getting uneasy just writing these scenarios. Of course, these two concepts are just part of safe practice, and there are many more ways to get hurt with machines. However, keeping these two basic principles in mind - and in action - will go a long way toward using machines safely.

Stay safe in the shop!

Here is some help with pencil lines on dark wood. Though knife lines can be modified to produce the advantage of a physical feel for the correct location of a tool such as a chisel, most layout in woodworking is done with pencil lines. Marking out the tails for tails-first dovetailing and curved layout lines for bandsawing are examples.

Graphite pencil lines have a bit of sheen which helps their visibility but I still find them difficult to see, particularly if the line is along the grain on a wood like Claro walnut, which is dark and has color variations. So, motivated particularly by my love of Claro, I have experimented with various white or light-colored pencil and ink lines.

I tried Japanese ink “brushes” and very fine point drafting pens. I do not like marking out in ink because I do make mistakes and have no immediate plans to cease, so no ink for me.

I have scoured art supply stores and experimented over the years with various white pencils, occasionally trying bright yellows and other colors. Most are too soft to retain a sharp point for a practical amount of work.

The best pencil I have found is the Sanford/Prismacolor Verithin White #734. It can be sharpened to a point that is nearly as sharp as a #2/HB graphite pencil. It wears faster than a #2 but the point holds up well enough, especially if used with a light touch. It makes a nicely visible line on walnut. It is not as easily erasable as graphite, but decently enough using a white “plastic” eraser. They cost from 39 cents to a dollar apiece, depending on the quantity and the store.

The top photo shows sets of three lines of #2/HB graphite and #734 White going across and along the grain, made from a single sharpening of each pencil. The graphite lines along the grain are barely visible just above the white lines. The photos below show the same lines photographed from different angles.

An alternative is a white 0.5 mm mechanical pencil refill stick made by Pergamano and available from McAllister’s. I have not tried these because they cost $10 for 10 sticks and I would be concerned that they would break easily. Also, the point of the Prismacolor pencil can be easily altered using sandpaper. This is a more fussy job with a less durable result using 0.5mm lead.

No matter what instrument is used for layout, visibility and accuracy are greatly enhanced by using proper lighting. The two simple rules are strong and adjustable. Strong mostly means close, and the light source must be moveable to avoid glare and to cast shadows only in favorable locations. Every effort should be made to set up good lighting.

White #734 sharpened, I’m ready to indulge in Claro.

From among my habits of work at the bandsaw, here are some that you may find handy.

1- The yellow velcro band placed around the blade is a reminder to tension the blade before work. Starting up the saw with a loose blade is not a happy moment (yes, of course, I’ve made that mistake) but it could be particularly damaging to a carbide-tipped blade. The velcro is placed aside during work so replacing it when the work is done is a reminder to release the blade tension.

2- Much has been written about proper blade tension, but like all tool adjustments, the goal is good performance. The same blade used to saw 8/4 stock will very likely need more tension when it is used for a 10″ resaw. Whether cambering a plane iron, choosing a bevel angle for a chisel, or tensioning a bandsaw blade, it always pays to “close the loop” by using feedback from the tool’s performance to confirm or modify the adjustments. Wood density, blade cleanliness, and heat build-up are just a few of the variables that make it unwise to tension the blade without thought. 

3- After installing and tracking a blade and before going to work with it, it’s a good idea to close the doors on the saw, run it for just a few seconds, wait until it stops completely, and then open the doors to check the position of the blade on the wheels and make sure all is OK.

4- It is easier to follow a layout line when it is viewed with both eyes (binocularly). Sometimes the blade guard or the guide bearing assembly will block one eye’s view of the line, depending on where you position your head.

5- When bandsawing freehand, I always think, “Feed the line to the blade teeth.” This is just the opposite of handsawing and I often have to remind myself to maintain the correct mentality at the bandsaw after I’ve been sawing by hand.

6- The push stick (below) has a rare-earth magnet which allows it to be stored within easy reach on the saw’s frame. The hole is a reminder of which end has the magnet. The short saw kerfs at the front end of the stick, which accumulate as it is used, can grip the corner of the wood as the cut nears completion. The stick has a limited life, of course, so the magnet is in a removable cup.

7- Large sawdust particles inevitably accumulate on the lower tire despite the actions of the wheel brush and the wood plate below the lower bearing assembly. A paint scraper held lightly against the tire as the wheel is spun by hand quickly removes the debris. A “synthetic steel wool” pad such as Scotch-Brite can also be used.

8- The variable-pitch, carbide-tip blade from Suffolk Machinery is a big help in resawing. It also is great for preparing leg stock and any other straight sawing of thick stock. Below is a 10 1/2″ wide Claro walnut board from Northwest Timber which I resawed with this blade. One of the many reasons why the bandsaw is so endearing.

I hope some of these tips prove useful in your shop.

This continues the frame and panel construction. So far, the panel template has been made, and now we must position and size the grooves in the frame and coordinate this with the panel thickness.

Rout the grooves in the frame parts with a 3 or 4-wing slot cutter bit. Use the appropriate bearing diameter, which will ride the straight and curved parts, to create the desired depth of cut. Allow for seasonal movement when planning the depth of the grooves in the stiles. (A straight bit, standing the frame part on its side, would be fine to cut the grooves in a straight edge, and though passable for a shallow curve, it is not ideal.)

Position the template on the selected area of the panel stock and secure it with double-stick tape. The thickness of the panel stock will be determined by the frame thickness and the location of the groove. In sizing a frame and panel, remember that the strength is primarily in the frame.

For example, in a 5/8″ thick small door frame, it would be reasonable to use a 1/4″ wide groove, positioned in the middle of the frame width, and a 3/8+” thick panel, raised 1/8+”. This will leave the face of the panel about 1/32″ below the level of the frame which will allow for finish planing or sanding the frame after glue up. The panel, of course, is finished before glue up.

Raise the panel by hand-held routing with a square edge dado/planer bit or a short-radius bowl-and-tray bit which leave a smooth finish. These use a top bearing and have a short cutting length (1/4″ to ½”) to avoid the need for a template thicker than 3/4″. Examples of these types of bits are shown in the photo above. Adjust the depth of cut to yield the desired thickness in the panel edge. You are routing an outside curve, so go counter-clockwise (as viewed from above), cross grain first, and make the cut in two or more steps as needed. (I will not advocate climb cutting but I will do it for a final pass if the grain direction demands it.)

The result of the cut is shown in the photo in the previous post.

For a square-profile field, I round the corners. I pin the panel at the center of its width on the rails, from the back, with brass escutcheon pins and nip off the excess and file it flush. 

My method suits my designs - the beauty is in simplicity and the wood but with a degree of design flair. The frame members have plain edges and the field profile is simple. The curve in the rail can be created without a template or router, even freehand, because the panel template is made directly from the actual frame.

By contrast, curved-edge frame and panel work with a sticking profile on the edges of the frame and an elaborate profile around the field of the panel usually involves a pair of offset templates, one for the rail, another for the panel. Bearing-guided router bits create the rail edge and a fearsome horizontal raised panel bit creates the edge of the panel’s field.

In summary, this method is another approach to a traditional construction - the frame and panel - that is suited for clean, simple designs with the added interest of the curved edge. The method is direct and it works.

A curved-edge frame and panel, especially an asymmetric curve, adds a nice flair to a piece. The curve is typically along one or both rails which are tenoned at both ends.

In general, for a frame and panel in my style of work, the panel is the star and the frame is the supporting cast. The panel is a highly figured, special piece of wood or at least contrasts with the frame. I find that a simple square profile or a very small radius cove bordering the raised field is the most effective way to display the beauty of the wood. An ogee or wide cove or bevel is a visual distraction from the effect I am trying to create.

In making a curved-edge frame and panel, it can be challenging to match the curved edge of the raised field to the curve in the frame member. I will describe a simple, reliable method to create an even gap between the field and the frame. Basically, the frame is made first, then a template for the field is made using the dry-fit frame as a guide. The template is placed on the panel stock and a short pattern-routing bit creates the field. The photo above shows the template still on the panel stock after raising.

Start by making the curve in the rail according to your shop drawing. I do this by measuring the key points on the wood and drawing in the rest with an Acu-Arc adjustable curve, or by making a 1/8″ MDF template to transfer a layout line to the wood. [Tips for laying out curves.] Two parts can be made to match by clamping them together for the final fairing of their curves. For efficient production work, though not fundamentally necessary for this method, a plywood or MDF template can be made and used to guide a pattern or flush trim router bit.

Complete the mortise and tenon joinery for the frame. Dry assemble the frame and place it on top of a piece of 3/4″ MDF or plywood. Decide on a width from the inside edge of the frame to the edge of the field. Find a small washer with a rim width that matches that measurement. Trace onto the sheet stock with a pencil point held against the inner rim of the washer while pushing the outer edge of the washer along the contour of the frame.

Carefully cut to the curved line and fair the edge, keeping it square to the face. Use your eye to match its curve to that of the frame, creating an even width between the template edge and the edge of the rail; make minor alterations as necessary. Then cut the opposite end of the template. If you are building during either extreme of the annual range of humidity, alter the width of the template along the stile edges to anticipate the seasonal movement. For example, if you are building at a very dry time, slightly reduce the width (crossgrain) of the field because it will only be larger at other times of the year.

The template can be used to help in your selection of the panel wood. Draw around its edge onto the proposed wood to see exactly how the panel will look. The template can be used from both sides for two symmetrically oriented panels such as on a pair of doors.

All of this makes for a very direct way to control the fit and appearance of the panel.

The next post will discuss using the template to make the panel.

In nearly all of my woodworking projects, there are curves that can make or break the design. These are almost always curves without a constant radius, so I am relying on what looks “right” to my eye. I really sweat this aspect of the design process.

Acu Arc flexible curves are my favorite tools for laying out curves. French curves in regular and Woodhaven’s giant sizes are also helpful for sections of curves.

I do not like flexible rules or laths for laying out curves because it is awkward or impossible to control the contour in mid-curve. The curve is determined by the endpoints and at least one intermediary point and is then subject to the material properties of the layout device which may not produce the desired contour. I rarely use trammel points or a compass.

To design curves in a project, I start by gathering ideas and drawing in my sketchbook. I refine the promising sketches with scale drawings, repeatedly erasing and redrawing. To produce a full size mock-up, the results get transferred onto wood by measuring the key points and laying out a smooth curve using the Acu Arc. Sometimes I go from sketches to drawing directly on the wood. The mock-up is refined with spokeshaves, planes, and especially rasps.

I spend a lot of time looking at the mock up, leaving it, and returning to see how it strikes me at repeat visits. The bottom line: when it looks right and feels right, it is right, and that is a happy woodworking moment!

I transfer the key dimensions of the mock-up and drawing to make a template in quarter-inch MDF, using the Acu Arc again to refine the final layout. MDF works better than plywood, solid wood, or cardboard since it holds a clean edge and there is no grain to distract my eye or tools. The edges of the template should be square if it will be used on both faces for legs or as a template for router work.

Looking down the curve, as shown in the photo below, is a remarkably sensitive way to see bumps and lumps that must be eliminated to “fair the curve.” Running one’s hand along the curve, like a sleigh ride over the hills, is also a very good way to sense smooth transitions and detect lumps and bumps which must be removed.

The Acu Arc has a natural tendency to produce a curve without bumps as you shape it to your wishes. Then you can hold it on the wood, and trace only a nearby section of the curve with a pencil, hold it further along, trace more, and so forth, proceeding incrementally. It is stiff enough to hold its shape when it is carefully lifted and turned over to form the mirror image curve on the adjacent face, as is usually done for making legs. It is made of translucent colorless plastic but I would prefer opaque plastic that would show the curve better against the background of the wood.

The AcuArc is available from Highland Hardware in 24″, 48″, and 72″ lengths, and from Lee Valley in 18″ and 36″ lengths. (The top picture in the online LV catalog shows the pencil too far from the hold-down hand - the Acu Arc will move.)

I label the templates, save them, and sometimes reuse parts of them in other projects. In due time, a style develops, and, who knows, maybe someone will notice.

At this point you very much want the piece to exist, to stand on its own, and so you are driven to build. You want it to “turn out” to be what you envision and hope for. Yet in between the compelling vision and the fulfilling object is the potential chasm of disappointment. This, frankly, evokes some fear.

To your rescue comes the teacher, and ultimately, the teacher is you. Let us consider what the teacher does, followed by an example for each:

• He charts an effective course. This is the strategic order of the steps of construction. Will you glue up the wall cabinet case before or after building the doors?
• He points out the critical junctures where you must bear down and get things right. Those last few plane shavings off the drawer sides greatly affect the fit and feel of the drawer.
• He alerts you to possible pitfalls, many of them sneaky. How will the figure change when a piece is shaped into a convex curve?
• He keeps a steady perspective on the big picture of the project, maintaining your faith. Are the little errors you’ve made so far going to significantly affect the final piece or should you not worry about them?

The teacher may be another person whose experience you borrow, but in due time (meaning after making your quota of mistakes) you must be your own teacher even as you remain a student. The important thing is to think through the four points listed above. Further exploration of how exactly to avoid that chasm of disappointment in creating a work in wood is a larger topic for another time, but the steps discussed in this series will go a long way to helping your project “turn out” the way you want it to.

As you build, there are still small but important decisions to be made because, as noted in the previous post in this series, drawings cannot fully represent the piece. This is much as a musician uses tools such as phrasing, articulation, and tone color to produce his personal interpretation of written music, staying within the fundamental conception of the composer.

Thus the music, or the woodworking creation, comes alive. You’ve done it, now it is there.

And yes, that is . . . happy woodworking. Best wishes to you as you pursue your ideas!