We asked Make: contributor Len Cullum to contribute some pieces on understanding basic tools and techniques. Here, he explains the tools used for laying out woodworking projects. — Gareth
Accurate layout work is the critical first step to a successful project. Without precise, repeatable marks, it is very difficult to get everything to come together at the end. So for this piece, I will go over some of the basic tools for measuring, marking, and transferring lines. My big three (actually four) tools for almost all of the work I do are the tape measure, a high quality 12″ combination square, and a .005 drafting pen. I also use a 4″ combination square for smaller work.
The three most common measuring devices you’re likely to find in a wood shop are the tape measure, folding rule, and steel rule. All three have their good and bad points. But as with all tools, find the one(s) that fit your style and make the most sense to you and the way you work.
The tape measure with its spring-steel blade rolled up into a small box is fast and can measure distances that would require a massive folding rule. On the down side, the little hook at the end of the tape can introduce inaccuracy. When new, the hook slides on rivets just enough to adjust for the thickness of the hooks metal. When measuring to the inside of something, the hook is pressed in; when on the outside, the hook is pulled out keeping the measurements accurate. This works great for a while, but over time, the holes and rivets can wear and get bigger, or worse. Far more common, the hook can be bent when the tape measure is dropped. To remedy this, most woodworkers “burn an inch.” This is where you ignore the hook and start all of your measurements from the one inch mark. This works well and gives accurate results, as long as you remember to subtract one inch from your result. Trust me, no one who uses this method hasn’t had a moment of dread after discovering something (or worse, multiple things) didn’t fit to the tune of one extra inch. So stay awake out there. When choosing a tape measure, consider the type of work you are doing. If you primarily work with material shorter than twelve feet, don’t buy a twenty five foot tape. Those last thirteen feet will never see daylight and the extra mass is heavy and cumbersome.
The folding rule overcomes the hook problem by having a fixed metal cap at the end of its wooden rule. This makes for worry free use, especially when measuring against something. It also has a nifty little sliding rule built into the end to measure depths and interior distances. On the downside, the thickness of the wooden blade means it must be laid on its edge to get accurate results and the way it folds creates a stair step shape that can make it awkward to use over distances.
The steel rule is a nice balance between the folders consistency and the tape measure’s small size, but its limitations are obvious. They are great for smaller work but once you get beyond the six inch mark, one of the above will have to take over.
Honorable mention goes to the story pole or story stick. This is usually a long piece of wood that one puts their own marks on for transferring measurements. This can be more reliable because it gets rid of all of those pesky numbers, and every distance is as marked. Story poles are especially useful when measuring larger projects with multiple components (like a kitchen or library) or when needing to transfer the same dimension over many parts. It helps eliminate measuring mistakes.
For layout work, a square’s primary function is to draw lines 90º perpendicular to a side. As always, there are a few types available but what sets them apart is what else they do. For me, a combination square is the most useful. Not only does it give me 90º and the occasional 45º, it also transfers measurements from one piece to another, finds the true center of a board, and checks depths and helps set up tools. It’s hard to imagine woodworking without it. Definitely spend up when buying one. Get the best one you can afford. A loose, out of square or hard to move blade creates more frustration than it’s worth.
The speed square is handy as well but is more suited to carpentry. I find the deeply stamped numbers to make for jaggy lines so I use it mostly for rough layout and marking. The sashigane is the standard square for Japanese joinery. It looks like a western framing square but has a much thinner, flexible blade. And also like the framing square, it is covered in mysterious, oddly spaced numbers and strange markings that when in the right hands can be used to figure and lay out some pretty complicated joints. Since I have yet to decipher one, those hands are not mine.
When it comes to making lines, thin, sharp, and readable are key. If a line is too thick or fuzzy (carpenters pencil) it’s easy to get lost as to where to cut or measure. Over the years, I’ve worked through a series of marking implements from #2 pencils (sharpen too much) to mechanical pencils (lead breaks too much) to knives (sharpening/lines can be hard to see) and even tried working with a bamboo pen for a while (never got the hang of it), but my favorite remains the .005 drafting pen. It leaves dark clear and very thin lines. I still use the others on occasion, pencil for rough layout and for places I might need to erase. Knives for when I need to cut to a super exact line. But for most situations the pen is king. Whatever you use, remember to mark a line only once. Multiple strokes not only darken it but make it wider and fuzzier and less accurate.
From the front: traditional ink line, modern ink line, chalk line
If you need to mark a straight line over a long distance, a snap line is the tool. A snap line is basically a reel of string that’s pulled through pigment and then, wait for it… snapped on a surface to make a line. The standard carpenters version has a string with a small hook that is pulled through a reservoir of (usually) blue chalk. To use it, you hook the string at one end of a board, pull the box to the other, stretch it taught and give it a snap. This leaves a reasonably good line for rough cutting. The downside is that this line tends to be wide, fuzzy, and that can be wiped or blown away, often by the tool that is trying to follow it. The Japanese ink line follows the same principal but a couple of differences. Instead of chalk, it uses ink for pigment, and it has a much thinner line with a pin instead of a hook. This allows for a very fine, dark, and accurate line that can’t be blown or brushed away. It also leaves that same ink on your fingers and everything else the string touches, so proceed with caution. Both kinds take a little practice to get the tension right and to keep the line from bouncing or snapping curved lines. They also have several different colors and permanence of chalk/ink available.
Last up is the marking gauge. Functionally, it’s like a combination of the adjustable square and a marking knife. While the shapes and styles available are endless, they are basically a bar with a blade or a pin in the end, attached to an adjustable fence. These are especially handy when transferring the same layout lines to multiple pieces and marking lines parallel to curved edges. They are quick and, if you keep them sharp, accurate and leave clean precise lines.
Bio: Len Cullum is a woodworker living in Seattle, WA. He specializes in building Japanese-style garden structures and architectural elements. It was a picture of a wooden kayak in the summer of 1992 that set him on the path he remains on today. The desire to build one, and the fear of it sinking, are what drove him to learn finer woodworking skills. After eighteen years of brushing up on those skills, and building lots of other things, he still hasn’t attempted that kayak.
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