Why I’m Switching To the Metric System in The Woodshop

Over the last several months, I’ve started using the metric system in the woodshop, and the more I use it, the more reasons I’m finding to love it.

Why am I using the metric system?

1. Many of my newer tools use the millimeter as a base measure
   1. Festool Domino
   2. X-carve CNC Router
   3. Laser
   4. 3D printer
2. Measurements are more comfortable to manipulate.
   1. No converting fractions to decimals
   2. Increments of 10
   3. The base unit is 1 millimeter not 1/16th or 1/32nd
3. Easier to Read
   1. One tic mark equals 1 millimeter
   2. No different length lines to get confused

Downsides

1. Finding tape measures and rulers
2. A natural understanding of 1 inch.
3. Plans and dimensional lumber are usually in inches.


The metric system was conceived by the French in the late 1700s. After the French Revolution, the French took the opportunity to start fresh with many things. They wanted to reform their unwieldy and archaic system of weights and measures. They invited other countries to take part, but the UK was the first to pull out. Thomas Jefferson championed the Metric system in the US but lost out to the Imperial System used by the UK. So the French went it alone. As years passed, the world converted to metric, except the notable exceptions of the UK and the US.

For the longest time, I didn’t see the appeal in the metric system. Then I started buying tools that had all their measurements based on metric sizes. I found myself using imperial rulers to set up tools that already had highly accurate measurement systems. After making a few mistakes, I realized how stupid I was and decided to put some time into understanding the system better. At the same time, I realized that all my CNC machines deflated to metric, and I regularly changed them to imperial.

Soon it became evident to me that the system was straightforward. My main issue was being unfamiliar with the spacial meanings. Having grown up in the US, I intuitively know how long an inch is, or a foot, or even a 1/16”. I have no apparent reference for a Millimeter or Centimeter. I realized that the only way to get over that hump was to start using it more in my shop. The hardest part has been trying to find a good quality tape measure with metric increments.

Once I started using metric for projects, I found several excellent side benefits. The first is that I find the increments much easier to read. You only have two marks, millimeter, and centimeter, and it’s in equal increments of 10. With my old eyes, I can read the tape measure more accurately. In most cases, I don’t need more accuracy than a millimeter, and I can decern a half-millimeter easily if required. If I need more precision, then I break out the calipers. Next, math is a whole lot easier and, therefore, more accurate for me. Multiplying 5 mm by 3 is a whole lot easier than 3 X 3/8”. Finally, I can use the accuracy of many of my tools scales—everything from Festool, my laser cutter, the X-Carve CNC router, and the 3d printer.

There are some downsides such as lumber and sheet goods in the US, come in imperial dimensions. Most plans that you buy or get online are in imperial, although that seems to be changing. Describing sizes to your friends can be a challenge, and most of the tools in my shop still have imperial measurements, although most of them are not as accurate as my newer tools.

So, here is my main takeaway: I need to know and understand both imperial and metric measurement systems. I will start using the metric system as much as I can to increase my spacial understanding and utilize the best measurement system for the job at hand. However, my feeling is that I will move more and more into the metric system.


Let me know what you think. Are you using the metric system at all? Do you find it more comfortable?