№ 000D: Metric Measuring Toolkit

Going metric is not as hard as you might think, it just takes the rare knowledge of how to do it in the best manner, as decades of experience in countries such as Australia has shown.

The hardest part is being brave enough to discard the dozen-plus separate medieval and ancient units that make up the U.S. collection of unit systems, and just start using metric.

Once you’ve made that decision, the process is straight-forward. First, stop measuring things in inches. You might be tempted to use the centimeter side of your existing rulers, but don’t. To make going metric easy, you need to ignore centimeters. Never ever, under any circumstances, write down measurements in centimeters, and try your best to never speak the word; but if someone else does, ask them to convert it to millimeters (as soon as you find someone that can’t do that conversion, you will understand the importance of this rule).

To buy all of these cool tools on Amazon (and help support the continued development of CFOG), please visit my Metric Measuring Tools page.

Metric-Only Ruler

This is the single most surprising part of metrication, at least to users of the inch. For people from long-metricated countries, I have a hard time convincing them that centimeters are evil, but about half of the U.S. and Canadian people I explain it to understand the issue pretty quickly.

You see, centimeters may be the closest thing in the metric system to the inch, but they are too big to measure just about anything without adding a decimal point and one more digit. That digit is measuring millimeters. So since you’re going to use millimeters anyway, you’re not avoiding them; you’re just making them more complex and longer. For nearly all measurements shorter than 1 meter, you’re increasing the number of characters by 33%:

To specify the height of ISO A4 paper in millimeters takes 3 characters (297), but using centimeters it takes 4 characters (29.7)!

The solution is to buy a millimeter-only ruler, the Shinwa H-101C.

Then get a banker’s box, put every single ruler that has inches and/or centimeters on it in the box, then stash it in the attic or garage.

Taper Gauge

That ruler is great for measuring flat things, but not so good at measuring holes accurately. When we start putting screws and bolts through existing holes (such as the mounting brackets on fire extinguishers), it isn’t that accurate. The Shinwa 15 mm taper gauge lets you insert it into any hole 15 mm in diameter or smaller, and get an accurate measurement.

Nearly Invisible Hooks

To keep the ruler and taper gauge handy, these Clear Command Wire Hooks will let you hang them on a kitchen wall, cabinet, or fridge, without fear of pulling the paint or finish off, or having a big-looking hook that’s a different color from the paint becoming an eyesore.

Millimeter Micrometer

When you need to measure the thickness of things such as cookie sheets or the diameter of screws and bolts, the ruler simply isn’t accurate enough. Later on, the OMGAI 0–25 mm Metric Micrometer will let us measure the thickness of skillets when we need to calculate their heat capacity. Once we get there, I’ll teach you how to adjust and measure with this tool. Prepare for a flashback to your high school chemistry lab days, where you learned how to measure with a vernier caliper.

Metric 32 mm Cabinet System Tape Measure

No, I’m not expecting you to start building your own cabinets, but the FastCap PMMR-TRUE32 5 m Measuring Tape is the only millimeter-only tape measure readily available in the U.S., and should you desire to have your next kitchen remodel use this type of cabinetry, you’ll be prepared to check the contractor’s work.

Just try to ignore the fact that the width of the tape itself is not metric (it’s 5/8″), that it uses horrible Phillips-head screws, and remember that the length of the tape measure body itself is not 2 3/4″, but is instead 70 mm.

A few of the other stand-out features of this tape measure are the belt-clip, which has a rubber-padded thumb lever (so that you can clip it to your pants or belt without having to struggle), a pencil-writable/erasable surface on the label, and two blade breaks—the normal one that locks the blade with a flick of the thumb, and a second momentary button under the bottom, for temporary holds with your index or middle finger.

The rest of the unique features are aimed at cabinet makers, but will help you occasionally:

  • A pencil sharpener.
  • Little dots every 32 mm, to mark the shelf support holes.
  • Every multiple 16 inches is marked with the number, to easily measure stud centers.
  • The heights and positions of the 32 mm system cabinet positions are marked.
  • There’s a set of golden rules printed on the rule that I think are awesome:
    1. Keep It Simple, Stupid.
    2. Remove the opportunity for mistake from the process.
    3. Set the next person up for success.

The 32 mm cabinet system was developed after WWII to streamline the extensive rebuilding construction that was happening under the Marshal Plan. The most recognizable feature are the shelf-mounting holes, 5 mm in diameter on 32 mm centers. Because there is no face-frame on this style of cabinets, the doors mount on hinges that screw into those shelf mounting holes, instead of the front surface of the cabinet. But the standard goes beyond that, in that all face heights plus reveal must be divisible by 32 mm. So you will see panels that are 768 mm (32 mm × 24) or 1024 (32 mm × 32), with the base cabinets having a 110 mm high toe-kick, bringing the top of the base cabinet up to 878 mm, plus another 18 mm for the counter top itself, brings the work surface up to 896 mm. You might notice that IKEA cabinets use elements of this system, in that at least the shelf support holes conform to it. Once I locate the official specification, I’ll cover this in more detail.

See the WoodWeb article, Panel and Door Balancing with 32mm Systems for a discussion of the finer details. Several manufacturers have created systems of manufacture aimed at the cabinet makers, and Ture 32 is one of those. The others are Blum (heights are based in inches, so not compatible with the actual 32 mm system), Kiss, Proulx, and Process 32; they differ in other dimensions, and may or may not be compatible with the strangely never-cited specification.

Tape Measure Belt/Workbench

To keep the tape measure handy, I recommend buying the manufacturer’s belt clip. It has a wide slot that makes it easy to insert the tape measure’s belt clip, plus a pencil holder and pencil sharpener.

But the best feature is a pair of holes on the belt clip, nicely marked “Bench Mount”. Later, we’ll use this to mount the clip to a convenient storage location, so that you can easily spot when the tool hasn’t been put back after use.

#2 Yellow Pencil

The Dixon Ticonderoga #2 HB is my go-to pencil. You’re not going to measure anything easily without a bunch of these. Good quality brand, great eraser, and enough you can lose a few.


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