While a tape measure is a great choice for distances up to about 16', for longer distances a laser distance measure (a.k.a. digital laser meter) is easier and faster to use, highly accurate and offers much more functionality.
It works by emitting a narrow beam of light and then measuring the time it takes for the light to hit an object and reflect back to the laser measure. Where the light hits the target you’ll see a dot (red or green), unless the target is very far away. Lasers that emit green light are brighter and travel farther while red lasers consume less battery power and the light beam is easier to see outdoors. Over long distances outdoors, laser dots are practically invisible. To overcome this, some lasers have a built-in optical viewfinder. Others have a built-in video camera that displays where the laser dot is on the unit’s display screen.
Entry-level lasers can measure distances up to about 100′, which is all most DIYers will need. Units designed for tradespeople are capable of measuring distances upward of 650′. Lasers can have either LCD or LED display screens. LED screens, which are more expensive, are much brighter and easier to read. Some lasers display measurements in Imperial units, others in metric and others in both standards. Accuracy can vary from 1/4″ to 1/32″ over a specified distance – often 30′ for entry-level lasers. Generally, as the distance increases, accuracy begins to falter. Along with measuring distance, some lasers can calculate area and volume, track minimum and maximum measurements, calculate angles of slope, and measure height or width of objects by triangulation. Most entry-level lasers don’t have memory storage or Bluetooth connectivity. This shouldn’t be an issue for DIYers.
Laser tape measures are essentially standard measure tapes (typically with blades that extend up to about 16′) that include a basic laser distance feature (that measure up to about 65′). They offer the advantage of both measuring options, making them practical tools for DIYers.
Types: Laser distance measure; Laser tape measure
Power source: AA, AAA or lithium-ion batteries
Price: $20 – $400
Reach: 20′ to 650′
Accuracy levels: 1/4″ to 1/32″
Screen types: LCD, LED
Don’t stare
Most LDMs use Class II lasers and are not directly hazardous to the human eye. However, it’s still a good idea not to stare into the beam or point the laser at anyone’s face.
Keep it clean
The laser emitter and receiver lens rely on an uninterrupted beam of light, so you’ll want to keep them free of dust and dirt.
Know what you need
Most lasers have multiple operating modes so it’s important to understand what you want to do with your laser. Hint – read the user manual.
Keep it steady
To ensure you get the most accurate results, keep your meter as stable as possible. Butt it up against a wall or lay it on a steady surface.
Mark the target
Outdoors, especially when it’s sunny, the laser dot can be hard to see on your target. Mark the target with a piece of masking tape or purchase a reflective laser target plate.
Carl Duguay - [email protected]
Carl is a Victoria-based furniture maker and the web editor at Canadian Woodworking & Home Improvement.
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