We are fans of old-school tools for boatbuilding, and one of our favorites is the folding ruler. Our 2′ folding ruler has performed admirably on many restorations and new builds, but recently we purchased a 3′ folding ruler made by Sybren of Holland, and it has jumped to the top of our folding-ruler class.

The first thing that caught my eye about the 3′ folding ruler was how the light-colored hardwood provides a sharp contrast to the black measuring marks and large numbers, making it easy to take measurements from plans or the dark corners of a workpiece. The markings are incised in the wood, making them much longer lasting than markings screen-printed on a flat surface. One side of the rule is marked in feet, inches, and eighths and the other is marked in feet, inches, and sixteenths. Completely folded, it is a 9″ ruler with eighth-inch markings showing; to get to the sixteenths, the ruler must be unfolded to its 18″ length. The numbers on both sides of the ruler read from left to right, and the increment markings are on the near side of the stick when it’s laid flat. Surprisingly, that is not the case with all folding rulers, the old Stanley rulers among them, which require looking over the far edge to measure or mark a workpiece.

All photos by Kent Lewis

Folded, the ruler is short enough to fit in a pants pocket without being completely buried and difficult to retrieve.

The Sybren ruler can be set on edge, which puts the increment marks in contact with the workpiece, offering more precise measuring and marking than is possible with a measuring tape, with its curved metal blade, which curls away from the work, or a zigzag folding ruler with joints that won’t let it lie flat. And, the Sybren hasn’t snapped back or pinched me yet.

This ruler’s major attribute is the versatility of having four rulers in one: 9″, 18″, 27″, and a full yardstick. I was pleased to find that the folded ruler was a more convenient fit in my pants pockets, with enough of the ruler poking out to make it easy to grab, even when wearing work gloves. My elusive 2′ folding ruler of a similar design, which is only 6″ long when folded, buries itself in pockets.

The ruler has two kinds of hinges. The two closest to the ends are almost completely concealed on the front side of the ruler and have a small barrel protruding from the back. The middle hinge extends only from the top edge.

The ruler is a standard four-fold style with sturdy brass hinges, which are stiff enough to create a rigid yardstick that provides more accurate measurements than a floppy metal tape. Measurements can be taken overhead or one-handed. The unmarked edge of the rule is useful to draw straight lines, and it is thick enough to stand on edge for the most precise measuring and marking. The center hinge is tight enough to provide friction to turn the ruler into a handy bevel gauge that fits into the same space as most other bevel gauges.

The hinges are tight enough to hold the position of the ruler when it’s partially folded, which can come in handy if you need a stand-in for a bevel gauge.

We used the ruler during construction of our Nutshell Pram and the 1/8″ markings were a good fit with the 3″:1′ scale of the plans. Originally invented in 1851, the folding ruler has stood the test of time in boatshops for more than 170 years, and the Sybren should span a few generations in our family.

Audrey (Skipper) and Kent Lewis recently completed a new build of Joel White’s 7′ 7″ Nutshell Pram, now the smallest in their armada of 16 boats. Their mess-about adventures are logged at their blog, Small Boat Restoration.

The Sybren folding ruler is available from The WoodenBoat Store for $24.95.

Is there a product that might be useful for boatbuilding, cruising, or shoreside camping that you’d like us to review? Please email your suggestions.