Basic Hand Tools for the Woodworker: The Carpenter's Level
Levels, like the Layout Square that I talked about in the last part of this series are essential tools that every woodworker/carpenter must have in his or her tool kit. There's more than meets the eye where buying and using levels is concerned. All levels aren't created equal. Quality matters so be prepared to pay for it when you go shopping for your levels. Yes, you will need to purchase more than one type and size of level if you want a well-equipped basic tool kit.
Levels and Their Construction
Levels have only one purpose in our lives, to make sure that our work is plumb (true vertically) and level. The bodies of contractor levels can be made of plastic, aluminum, or hardwood. The plastic and aluminum bodies are usually in the form of an I-Beam, while the hardwood bodies are solid. The price of a carpenter's level can run from around $10 to over $150 depending on their size (length) and quality. When you consider the cost of quality building materials today that's not such a high price to pay for a quality tool. The aluminum I-Beam level is the strongest and can withstand a few bumps and drops before their accuracy is affected. Personally, I prefer the hardwood models. Wooden carpenter's levels are made of handsome and very stable woods like rosewood, ebony, and mahogany. They require more care than an aluminum or plastic level but they're more accurate and less effected by climactic conditions than aluminum ones. Some levels come with end caps. Don't buy one. The seam that it makes with the rest of the level's body is a big source of accuracy problems.
The material that a level's body is made of is important but the main key to its accuracy is its sealed glass or plastic bubble tube. This tube may contain water, alcohol, chloroform, or some other clear liquid. This slightly curved tube isn't completely full of the liquid but contains the all important air bubble. The size of this bubble is a key to the level's accuracy and it's one of the first things a knowledgeable buyer checks when buying a level. A bubble can be too large or too small. The perfect bubble is one whose ends just touch the lines on the vial. The bubble of the highest quality levels react quickly to the slightest movement of the level's body. Look for levels where the glass vial is covered with a protective glass plate to protect the vial from breakage. The best levels also have vials that are replaceable by the owner.
Carpenter's levels come in two-foot, four-foot, six-foot, and eight-foot lengths. For most of the two-foot and the four-foot lengths will suffice. The two-foot and the four-foot levels come with three vials, one mounted at each end of the body mounted transversely with the one mounted in the center mounted lengthwise. The two transversely mounted vials assure true plumb when the level is used vertically and the lengthwise mounted vial assures true level when the level is used in the horizontal position. The four-foot level is the one you will use when installing cabinets and framing a wall but the two-foot level is the one you'll use most of the time. Still, you will need a few other levels in your tool kit right from the start. The nine-inch torpedo level and the line level are two of those levels.
The torpedo level is the handiest level you can have when working in tight quarters. It fits comfortably in a pants pocket or a tool belt pouch. It's the perfect level to use when mounting electrical boxes and electrical panels, or when running electrical conduit because you can carry it right in your tool pouch.
The Line Level is exactly that, a small level that is designed to be hung from a taught line. The Line Level is mostly used by masons but it comes in handy when installing dropped ceilings. They make snapping a level line a breeze even when the old ceiling isn't level.
How to Check A Levels Accuracy
Before buying any level, new or used check its accuracy. You can do it quite easily. All you need is a flat, horizontal surface and it doesn't have to be a perfectly level surface either. Place the level on the surface and make a mental note of the position of the bubble in the center vial. Flip the level 180-degrees and note the position of the bubble in the center vial. If the position of the bubble is the same in both positions, the level is accurate.
Next up, the framing square.