8
Mobile nozzles
Check there is enough emery in the pans.
Use the tank switch (D) to select the tank. The colour
coding system used makes it easy to see which is the
active tank at all times.
Pick up the mobile gun selected inside the chamber.
The colour of the gun’s nozzle-holder matches the
colour on the tank covers (red, blue, yellow, green).
When the gun has been selected, press the drive pedal
to begin sandblasting.
Direct the blast carefully to prevent the stream hitting
the sides of the chamber directly, since this could
damage the chamber. If you wish to test the blasting
pressure or strength, direct the stream at the rubber
dolly inside the chamber.
After the blasting operation, release the pedal,
stopping the sand flow and activating immediate air
discharge to relieve pressure in the tanks. Then
switch off the suction unit, open the lid of the
chamber, and take out the part.
Maintenance and cleaning
To ensure a lengthy service life, we recommend the
following:
Always use approved quality emery -
Talleres
Mestraitua, S.L
. recommends
MESTRA
emery.
The mobile blasting guns with nozzle diameters 1.25
mm and 1 mm can respectively blow emery of
maximum diameter 250 and 150 microns. The mobile
blasting gun with nozzle diameter 0.75 mm can blow
a maximum diameter of 75 microns (see the table).
The gun (Ø 3 mm nozzle) can blast aluminium oxide
up to particles of Ø 300 micron.
In case of obstruction of the gun, dismount the nozzle
holder. Clear the nozzle by blowing in the opposite
direction to the air flow, or, if needed, by using a pin
or a thin wire. Then set the gun again, making sure it
is correctly centred.
If the nozzle came loose, glue it to its holder with
cyanoacrylate. The nozzle should be level with the
inner surface of the nozzle holder, to make sure that
the distance from the injector to the nozzle is 4.5 mm
and the Venturi effect takes place.
It is preferable to use dry-piston air compressor units,
since oil in the air could cause the sand to compact
and obstruct the gun nozzles.
Never fill the modules with emery deposited on the
floor of the chamber, since particles with large
diameters could obstruct the nozzles, and this emery
is now contaminated with particles eroded off the
parts blasted.
The silencer filters inside the tanks must be replaced
every 5000 or 10000 operations (around 1 or 2
years). The incoming filter fittings on each tank must
be replaced every 500 or 1000 hours (much depends
on the quality and size of the sand used). Original
MESTRA spare parts must always be used.
To prevent any abrasion wear on the walls inside the
chamber, take care not to direct the stream of emery
directly onto the walls.
Clean out the emery inside the chamber on a periodic
basis, using the practical emptying plug inside.
Any water which has condensed inside the incoming
air filter must be bled out regularly. The chamber has
a window to view the amount of water in the filter.
Use a soft cloth for general cleaning of the unit.
If the guns become obstructed, remove the nozzle-
holder and take out the nozzle. Unblock the nozzle by
blowing in the opposite direction to the flow of air, or
use a pin or a thin wire to unblock it, and then refit
the attachment.
The blasting module guns on the 2-tank Eclipse
model are supplied ex-works with nozzles 1 and 1.25
mm in diameter. 0.75 nozzles, however, may also be
used with this model (consult your
MESTRA
distributor).
The maximum diameter of emery particles in relation
to nozzle diameter is shown in the table below:
MAXIMUM PARTICLE DIAMETER /
NOZZLE
Nozzle
Diameter
1.25 mm
Up to 250 microns
1 mm
Up to 150 microns
0.75 mm
Up to 75 microns
Precautionary measures
Never exceed 6 bars of pressure. Optimum working
pressure is between 2 and 5 bars.
Operations should always be carried out with the lid
of the chamber closed, with suitable protection.
Masks and goggles should be worn.
Connect the chamber’s outgoing tube to a suction
facility.
The protection sleeves (H) must be replaced
immediately following any tearing or damage.
Do not allow children or unqualified staff to operate
the unit.
Use only guaranteed-quality materials as emery (we
recommend
MESTRA
emery). Poor quality emery
