Correction Of Spray Pattern; Retooling And Repairs; Replacement Of The Material Needle; Replacement Of The Defective Needle Packing - WALTHER PILOT PILOT II Instrucciones De Servicio

6.1 Correction of Spray Pattern Imperfections
The following table shows how to correct a defective spray pattern.
Desired Spray Pattern
Spray pattern Fault
test
Spray pattern is split in
the centre
Spray pattern is too thick
at the ends
The spray pattern shows
rather large droplets
Material application in the
centre of the spray pattern
is very thin
Spray pattern is split in
the centre
Spray pattern is very
spherical
7 Retooling and repairs
If a jet contour other than already described is desired, the spray gun has to be
retooled. The suitable material air control head, material nozzle and needle-combina-
tion form together a unit - the nozzle set. Always change the complete insert assmbly
to maintain the desired finish quality.
Warning
Prior to any retools or replairs: Make sure that the spray gun is in depressurized con-
dition, i.e. all air inputs must be shut off - if not, imminent Risk of Injury.
Note
In order to perform the following procedures, please refer to the exploded diagram in
the beginning of these operating instructions.
7.1 Replacement of the material nozzle and the air control head
1. Remove air cap (Item 1) from the gun body (item 4).
2. Remove material nozzle (Item 3) from gun body; using a Size 11 wrench.
Reassemble in reverse order.
Required adjustment
• setting a wider spray pattern
• S etting a more rounded spray
pattern
• Increase the nozzle air pres-
sure
• D ecrease the nozzle air pres-
sure
• Increase the nozzle diameter
• Reduce nozzle air pressure
• Increase material pressure
• Reduce material pressure
• Increase nozzle air pressure
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7.2 Replacement of the material needle
1. Unscrew the spring bushing (Item 12) from the gun body.
2. Withdraw the needle spring (Item 11) and pull out the material needle with
both needle retaining nuts.
3. Remove the material needle.
4. The setting dimension for the needle-controlled initial air input is 69 mm,
measured between the point of the material needle and the face of the 1st
needle retaining nut (Item 13), with the 2nd nut serving as lock nut.
Reassemble in reverse order.
7.3 Replacement of the defective needle packing
1. Remove the material needle, see above.
2. After the remove of the material needle unsrew the packing gland (Item 8),
using a properly sized screwdriver. The packing (Item 7) can now be removed
from the gun body (Use a thin wire, one end of which is bent into a hook, for
this purpose).
Reassemble in reverse order!
8 Cleaning and service
Attention
Never immerse the spray gun in solvent or any other cleaning solution. The functio-
nal reliability and efficiency of the gun can otherwise not be guaranteed. Do not use
any hard, sharp or pointed objects when cleaning the spray gun. WALTHER is not
responsible for any damage resulting from improper cleaning.
The gun does not need to be dismantled for cleaning.
1. F ill the cleaned gravity-feed cup with a cleaning fluid compatible with the spray-
ed material.
2. Operate the spray gun.
3. Do not stop the spray gun until clear cleaning fluid emerges from the nozzle.
The entire system should then be depressurised until the gun is used again. Clean
the spray gun only with cleaning agents which have been recommended by the man-
ufacturer of the sprayed material and which do not contain the following constituents:
• halogenated hydrocarbons (e.g. 1,1,1-trichloroethane, methylene chloride, etc.)
• acids and acidic cleaning fluids
• regenerated solvents (so-called cleaning thinners)
• paint removers
The above-mentioned constituents cause chemical reactions on electroplated com-
ponents, resulting in corrosion damage.
Clean the spray gun
• before each change of spraying material
• at least once a week or
• several times a week if required by the spraying medium and depending on
the degree of fouling.
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