DeWalt’s 20-volt 3 x 360-degree line laser emits three laser beams that appear on solid surfaces as lines but are, in effect, laser planes because those lines radiate from the instrument in all directions (360 degrees). It shoots a horizontal level plane, a vertical plane that runs perpendicular to the level plane, and a second vertical plane that runs perpendicular to the first vertical plane and also runs perpendicular to the horizontal plane.

When I tested this instrument for accuracy, I found that it exceeded DeWalt’s listed specification of 1/8 inch over 30 feet for level. One particularly helpful feature is an adjustment knob that fine-tunes the position of the plumb plane, which is visible on the floor, up the wall, and back over the ceiling. It can be used for many tasks, among them setting a door jamb plumb, marking stud and ceiling joist locations for attaching drywall, and laying out tile on floors and walls.

After confirming that the level and plumb planes were dead on, I used a bit of geometry that I learned in the 1970s to confirm that these planes ran at true right angles to one another (see Testing a Laser for Accuracy).

Seeing the lines. Lasers don’t operate much better than your average vampire when subjected to direct sunlight. Even with the best green lasers, the visibility of the line fades rapidly in sunlight. When I tested the DeWalt 3 x 360 for level inside my house, the green laser line was crisp and bright 50 feet from the instrument. Even when I tested it at 130 feet inside, I could clearly see the line, though admittedly the day was gray and overcast with little sun coming through the windows, and the interior lighting was fairly low. At that distance, the line measured about 7/16 inch wide, but it was easy to see.

Under normal interior lighting conditions, the green horizontal line and two vertical lines of DeWalt’s 20V Max 3 x 360 green beam laser are clearly visible for up to 50 feet.
The laser has a handy adjustment knob that can be used to fine-tune the position of the vertical plane, shown here projected onto the string line of a plumb bob.

When I tested the laser outside, though, the beam faded quickly. In direct sunlight, I could barely see the beam 6 feet from the instrument. By shading the area where the laser line struck, I could make out the line 35 feet away, but it was very faint. In a tree-shaded area, with additional shade over the surface where the laser line struck, I could discern an extremely pale line at 85 feet. At that distance, the laser line was not only faint; it was also only about 5/16 inch thick.

There is a solution if you need to use this instrument outdoors. DeWalt offers a Laser Line Detector (DW0892G) that detects the laser 165 feet from the instrument. It’s easy to use and very accurate. This detector, which costs about $120, must be purchased separately.

DeWalt's DCLE34030G kit comes with a 20-volt battery, a charger, a bracket for attaching the laser just below ceiling height, and a hard plastic case.

The bottom line. This laser has it all. It’s self-leveling. It can be set up on a tripod, but it works fine when set on any flat surface that’s roughly level. It’s very accurate in level, plumb, and the horizontal and vertical right angles it makes. It has a long run time of up to 10 hours; it’s debris and water resistant; and its fine-adjustment knob is handy. The DCLE34030G kit comes with a 20-volt battery, a charger, a bracket for attaching the laser just below ceiling height (for running ceiling grid for commercial work), and a nice hard plastic case with compartments that hold all the components snugly in place. It’s well worth the price of $580. If you do a lot of outdoor work, plan on investing another $120 for the detector.

Photos by Matthew Navey.