reasons for Rules
There’s a strange relationship between our tools and work habits. The methods of work you follow over the course of a project influence the kinds of tools you use. Likewise, a new tool can change your routines leading to different patterns and better results. Allow me to illustrate with a personal example.
I had a contractors-style table saw in my shop. As much as I liked its capabilities, the rip fence locking mechanism didn’t keep it parallel with the blade. I had to double-check the setup with a rule measuring from both the front and back of the blade.
Back in the shop at Woodsmith, the rip fence scales couldn’t be trusted since either standard or thin-kerf blades might be in the saw at any given time. You never knew what blade the scale was calibrated to. The solution: I carried a rule with me every time I used one of the table saws at work, too.
The downstream result: with a metal rule acting as my trusty sidekick, I started using it more and more for measuring and marking. Shake that well with several years of use, and voila a new work habit is ingrained.
I get it, using rules for woodworking sounds about as revolutionary as electric light. Another fact: there are other ways of working that yield excellent results. However, I’ve learned much from other woodworkers and understanding their processes. It makes me examine my own preferences and I often come away with something to think about adopting.
BIGGER IS BETTER (SORTA).
For the scope of this article, I’m suggesting you adopt a rule that’s no shorter than 18" long as part of your everyday measuring kit.
Trying to be more specific than that presents some challenges. First, I don’t know a thing about the kinds of projects you build or the tools in your shop. Second, and almost as important, personal preference plays a big role.
Let’s walk through some of the options. An 18" ruler is the big brother of a 6" rule most folk keep in their aprons. It’s thin and flexible. This rule is light in weight. The markings are etched and easy to read. For sources of these rules, turn to page 46. I like rules that have a centering scale on one edge, as shown in the photo below. This feature makes some tasks simpler and quicker to accomplish.
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| Some rules offer a centering scale on one edge. This comes in handy for laying out symmetrical details or when sizing glued-up panels based on a joint line. |
A STEP UP.
It seems reasonable that stretching out the 18" rule to 24" would offer a step up. However, I’ve found that thin rules at this length get a little too floppy. The sagging rule snags on the edges of a workpiece. It can also develop a permanent bend. The solution is to switch to a thicker rule. The 24" rule shown is made from 1⁄8"-thick aluminum. This offers a good balance of weight to rigidity. These rules are wider, too (21⁄2"); this increases their usefulness as a reliable straightedge.
As I said, tool preference is subjectve. However, I find that a 24" is too “in-between” for the job. Too short for many project parts and too long to be substantially better than an 18" model.
GO LONG.
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| Watch out. The thickness of a ruler can hinder accurate measuring and marking. Bevelled edges (red ruler) offer better precision. |
In my experience, true capability comes from a rule that’s at least 36" long. You may think this would be clumsy.
Rather, I find the size to be an advantage. The extra mass keeps the rule in place on drawings or a workpiece. You will not easily misplace it among the detritus of the shop. Only rare, large projects require measurements beyond its reach.Two other formats are shown above. One is a wide aluminum rule that falls between the basic rule and the thicker version I was just talking about.
Another option to consider is a wood rule. This can be a basic, hardware store yardstick. Or a premium version made from hardwood with brass-bound ends and finer markings. A wood rule may seem like a throwback. But it offers light-weight and decent accuracy.
One thing to be aware of is parallax. This is the visual distortion caused by the thickness of a rule that can throw off a measurement.
Precise to The T
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| Whether commercial or shop-made, a T-square rule is a reliable way to ensure a square layout from the get-go. |
For the most part, a plain, straight ruler offers more versatility than feature-studded layout systems. There’s a case to be made for an exception: the T-square ruler. A lot of woodworking depends on square joinery and assembly.
WOODPECKERS T-SQUARE.
The head on the Woodpeckers version features a ledge that rests on the workpiece (inset photo). This keeps the rule from tipping in use. Beveled edges bring the marking close to the surface. A series off indexed holes allow you to mark lines parallel to the reference edge.
SHOP-MADE.
Another option is designed by our very own Chris Fitch. It uses a 36" wood rule as the base. He designed an adjustable head that can be clamped anywhere along the length. Check out sources on page 46 for details.
RULES AT WORK
It should come as no surprise that the primary use of a metal rule is to measure and mark dimensions on a workpiece. Long rules handle those tasks easily. The qualities of long rules allow you to use them in other roles as well.
MACHINE SETUP.
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| Butt one end of the rule against the blade. A thin rule can tuck under the stop block on a miter gauge for an accurate reading. | Using the same rule for layout as well as machine setup gives you greater consistency in the results of your work. |
At the beginning of the article, I mentioned the reason for using a metal ruler in the first place — setting up a table saw. A rule allows for a direct measurement when setting up a stop on a miter guage (or a crosscut sled).
The rigid rule contacts the blade for a fixed reference surface. The same holds true when positioning the rip fence. I can easily line up a saw tooth with the measurement I need.
There’s a side benefit here: using the same tool for layout work and machine setup ensures consistency. The scale on the table saw doesn’t necessarily match the rule you used. The same rule can then be used to set up the router table, band saw, or miter saw.
STRAIGHTEDGE.
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| A long rule serves as a tool guide as well. That could be as simple as a fabric/veneer cutter or guiding a router or circular saw. |
There’s more to a long rule than just the numbers etched on the surface. The very nature of a straight, rigid rule means that it also works well as a reference edge. For example, in the photo above, I’m cutting some felt to line drawers in my tool cabinet. The fabric cutter is guided by a rule for straight cuts. By the way, that same fabric cutter works for cutting veneer as well.
You can step up the concept to power tools. A rule can serve as a guide for routing dadoes or cutting plywood panels to size with a circular saw. A rule can also serve as the basis for making jigs. I used one as the heart of a circle-cutting trammel. You can find the video on our YouTube channel.
DETECTIVE WORK.
As a straightedge, a long rule allows you to find and fix elements of your tools and projects. A straightedge rule serves as a guide for leveling the router table insert plate or a table saw insert.
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| Well-made rules serve as straightedges for tasks like leveling insert plates on the router table or table saw. |
When one of the band saws wasn’t cutting quite right, a long rule determined that the problem was that the wheels weren’t in the same plane, as shown in the photo below. Your aim in gluing up a panel is to end up with a flat surface. During the process you need to know where to focus your attention.
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| A long rule give you the ability to diagnose whether or not the wheels on a band saw are coplanar. |
A straightedge and a low, raking light reveal the hills and valleys. You can see this in the photo. Slivers of light under the rule show the low spots that I’ll need to work down to.
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| Combine raking light with a precision straightedge and you can ferret out the high spots when flattening and smoothing a glued-up tabletop. |
A BASIC KIT.
When I started woodworking, the universally accepted starter kit of measuring tools was a 12" combination square, a 16' tape measure, and a 6" rule. Now, I’m not so sure that’s the only way to go. My projects consist of tables, cases, and boxes — pretty common furniture making. My advice to new woodworkers would be a different set of three: a 6" rule, a 6" adjustable (or combo) square, and a 36" rule. The tape measure can stay out in your truck for trips to the lumberyard.
Tell me a Story
One important woodworking lesson is that sometimes numbers can get in the way of accurate work. The better choice is a direct transfer of dimension, size, or location. The tool for this kind of work is called a story stick. A long rule can stand in for a story stick.
Most of the time, I mark right on the rule with my pencil. Just make the pencil mark distinct from the hash marks. If your rule is made from anodized aluminum, marking with a pencil is out of the question. Blue tape to the rescue. A strategically placed strip of masking tape creates a distraction-free marking surface.
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| Satin-finished rules allow for direct marking with a pencil or marker, as shown above. Masking tape is a better choice for anodized rules. |
