No woodworking project can be a success without doing some measuring and some laying out of parts. There are an amazing variety of tools from elegant and high tech to ugly and low tech to get the job done. The most important thing is accuracy. While there might be some fudge factor in banging together a temporary gate to keep the dog out of the garden, when it comes to getting a good fit on a cabinet door or drawer, measurements are key.
The two primary ways to assure accurate measurements are by direct measure using a ruler, protractor, etc and by reference, using tools such as a story stick, bevel gauge, or pantograph. Let’s move first to direct measurements:
- Rulers – There are more variety’s of rulers than you can shake a stick at (sorry, I couldn’t resist.) Most of us are pretty familiar with the standard 12″ wooden ruler of our school days. We probably have one somewhere in the house. While wooden rulers are familiar and common they are not the best ruler for the workshop. Wooden rulers get dinged up, the metal edge falls out and the paint peels from the numbers. Additionally, most wooden rulers have only relatively coarse fractions – from 1/8th ” to 1″ segments. In fine woodworking the tolerances may call for 16th, 32nds or even 64ths. Also, some plans call for metrics and those can be quite hard to read on wood. For clarity and durability I would recommend metal over either wood or plastic. In my shop I have three ruler sizes; a 3ft, 12″ and a finely detailed 6.” My 6″ is thin bladed allowing it to be used for precise, close in detail. True, I need really good light to read it these days but with 1/64th increments on one side and millimeters on the other side I can get as exact as I need to be. This is the ruler I use every day on almost every project.
- Tape measures -The advantage of a tape measure is the distance it can cover. The disadvantage is a lack of accuracy. Manipulate the metal tab on the end and you’ll see how much play it has. Tape measures are good for getting an overall length, for checking diagonal corners for square and similar large scale tasks. They have a proper place in the shop, if they are properly used. One practice to keep in mind is to use the same measuring tool for each similar task. For instance, if you use a tape measure to measure one side of a cabinet, use the same tape measure for the other side and for the back. This way, all of your measurements will be consistent.
- Tri-squares – The most common angles in woodworking are 45° & 90°. Basically, a square edge and a miter. For these two the ideal tool is a tri-square. This basically a metal ruler with a sliding head. One side of the head is 90° to the ruler and the other is 45 ° to the ruler. For everything in between you need a protractor.
- Protractors – Protractors are a semi circular tool with angle gradations around the top. This allows you to place the flat edge against one side of your work piece and then mark any angle you need. If, for example, you wanted to make an octagon shaped mirror you would set the flat edge against the long side of your board and use the protractor to mark the end at 22.5°. If you took geometry in high school protractors will be a simple addition to your tool box. If, like me, you skipped that class they’ll take a little getting used to.
With these four tools: Tape measure, ruler, tri-square and protractor you can create all the measurements you need for any project. That being said, there are countless ways to refine and simplify those measurements. As you practice your craft you’ll find some measuring tools easier and more comfortable for your needs. When you discover a favorite, find a hand place to keep it and put it there every time you are finished for the day – you don’t want it to go missing just when you need it the most!
Source by Protechwood