Dot laser level: when you need one and how to choose between 3 and 5 dots

The dot laser level is used to transfer a reference from one point to another, for example from floor to ceiling, or to align a square. It does not mark lines: it projects dots. In the collection you will find 3- and 5-dot models, with red or green beam, accuracy from ±2 to ±4 mm at 10 m and a visible working distance of 30 or 45 m.

Types

• 3-dot laser level. It projects three references, enough for a simple alignment or a plumb line. An example is the SPL3 multi-dot laser level with red beam.
• 5-dot laser level. It adds further references: the plumb dots are used to go from floor to ceiling, the side ones to align and check squareness. These include models such as the FatMax SPG5 5-dot green beam, the FatMax 5-dot red beam and the 10.8 V lithium DeWalt DCE085D1G-QW (green) and DCE085D1R-QW (red).
• Line marker with dots and lines. The DeWalt green beam line marker combines two cross lines at 90° with the 5 dots: it is for those who want dots and lines in the same instrument.

How to choose for the job

Before looking at the model, ask yourself what you need to transfer: a point from one height to another, or a line to follow. In the first case you need this instrument. In any case, where you work matters: dots are small and in very bright environments they are harder to read.

• Fitting suspended ceilings, tracks and ceiling-mounted services. A 5-dot: you transfer the position from floor to ceiling with the plumb dot.
• Laying partitions and walls. A 5-dot to align the base with a reference and check the right angle.
• Aligning machines or furniture on a plan. A 3- or 5-dot to be positioned on the floor reference point.
• Those who mainly mark long lines on a wall. A line level is more convenient: the dot level is designed for transferring and squaring, not for marking.

What to look for

• Number of dots. 3 or 5. If you only need to align, 3 are enough; if you also need to carry the plumb and check squareness, you need the 5.
• Beam colour. Green or red. Green is easier to see in strong light, red is fine indoors.
• Accuracy. From ±2 to ±4 mm at 10 m. The tighter value is needed when the dot transferred from floor to ceiling has to land exactly on an axis.
• Visible working distance. 30 or 45 m: more than enough for indoors, even large spaces.
• Levelling time. Up to 3 or 5 seconds: this is the time the instrument needs to level itself.
• IP protection rating. IP50 or IP54. IP50 protects against dust but not water, IP54 also against splashes: don't leave it out in the rain.
• Power supply. AA alkaline batteries or internal lithium battery.

Common mistakes

• Taking a dot level to mark lines. For long lines you need a line level or a cross-line laser.
• Not locking the pendulum during transport. A knock with the pendulum free can shift the calibration.
• Never checking accuracy. Check it now and then, especially after a drop.
• Resting it on an unstable surface. An unsecured stand makes the dots move.

Frequently asked questions

Dot level or line level?

Dots if you transfer references between floor and ceiling or check a square. Lines if you mark long alignments on walls.

Are 3 dots enough or do I need 5?

For a simple alignment 3 are enough. If you also want the plumb dot to the ceiling and angle checks, choose 5 dots.

Is it better to choose a green or a red beam?

Green is easier to read, especially in bright environments or on light-coloured surfaces. Red is fine if you work in poorly lit environments.

How often should I check the accuracy?

Now and then, and always after a drop or a rough journey. If the dots no longer match a reference you know, don't use the instrument for jobs that require accuracy.

Can it be used outdoors?

The collection's IP50 and IP54 ratings indicate limited protection. Outdoors in strong light the dots are hard to see, and a level with a receiver is the better choice.

You will find the models in the dot laser levels collection; to choose the right one for your site, request a quote or ask the AMES technicians for advice.