Practical Advice; Example Applications - Bosch GTL 3 Professional Notice Originale

18 | English
The maximum permitted deviation over the measuring
distance of 4 × 5 m = 20 m is as follows:
20 m × ±0.4 mm/m* = ±8 mm. The discrepancy d
between points Ⅰ and Ⅶ must therefore amount to no
more than 8 mm.
* The value of ±0.4 mm/m is based on the angle accuracy
of ±0.2 mm/m plus a potential uncertainty of 0.2 mm/m
when rotating the measuring tool.

Practical Advice

Only the centre of the laser line must be used for
u
marking. The width of the laser line changes depend-
ing on the distance.
Always place the measuring tool flat on the floor
u
or mount it level on the wall. If the measuring tool is
not placed flat or mounted level, the angle is less than
45° or 90°.
Never align using the laser lines that the measur-
u
ing tool projects onto the wall when the tool is po-
sitioned on the floor. The measuring tool is not self-
levelling. Therefore, the line on the wall is distorted.
Only ever place the measuring tool on a clean lev-
u
elling plate. If the surface of the levelling plate (10)
is uneven or dirty, the measuring tool is not level and
may give false measurement readings.
The reference point with which to align tiles is the inter-
section point P of the laser lines just in front of the meas-
uring tool. To transmit an angle, the measuring tool must
be rotated around this intersection point (see figure F).
Working with the levelling plate (see figures D–E)
You can use the levelling plate (10) to lay the measuring
tool flat on uneven or soft ground.
The levelling plate (10) can also be used to mount the
measuring tool to walls. Secure the levelling plate firmly
in place on a wall or an angled surface so that it cannot
slip, e.g. using commercially available screws. Use a
spirit level to ensure the levelling plate is positioned level
on the surface.
Positioning the measuring tool on the levelling plate:
Use the magnets (4) on the base to affix the measuring
tool to the levelling plate (10). Use the grid of lines on
the top of the levelling plate as an aid to position the
measuring tool precisely. To transmit 90° or 45° angles,
place the levelling plate on a reference edge or on a pro-
1 609 92A 4HU | (16.01.2019)
jecting section of wall and position the measuring tool as
depicted on the top of the levelling plate.
Working with the Laser Target Plate (see figure A)
The laser target plate (9) improves visibility of the laser
beam in unfavourable conditions and at greater dis-
tances.
The reflective half of the laser target plate (9) improves
visibility of the laser line. The transparent half enables
the laser line to be seen from behind the laser target
plate.
Laser Viewing Glasses (Accessory)
The laser viewing glasses filter out ambient light. This
makes the light of the laser appear brighter to the eye.
Do not use the laser goggles as protective goggles.
u
The laser goggles make the laser beam easier to see;
they do not protect you against laser radiation.
Do not use the laser goggles as sunglasses or while
u
driving. The laser goggles do not provide full UV pro-
tection and impair your ability to see colours.

Example applications

Checking right angles (see figure A)
Set the measuring tool in a corner of the room and posi-
tion it so that the 0° laser line runs parallel to the refer-
ence line (e.g. wall). Measure the distance between the
laser line and the reference line directly next to the
measuring tool and again as far as possible from the
measuring tool. Align the measuring tool so that both dis-
tances are equal.
Then, from at least two different points, measure the dis-
tances between the 90° laser line and the wall. If the dis-
tances to the 90° laser line are equal, the walls are at
right angles.
Laying tiles in a square arrangement (see figure B)
Set the measuring tool in a corner so that the 0° laser line
runs parallel to a wall. Lay the first square tile at the
point at which the 0° and 90° laser lines intersect.
Laying a diagonal arrangement (see figure C)
Position the measuring tool so that the 45° laser line
marks the diagonal angle of the tile grout.
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