TM55-1500-345-23
between equipment manufacturers and local con-
(3) Associated Electrical Equipment. As
required by manufacturers.
ditions. Each manufacturer's instructions and
other details must be consulted. Special consi-
deration should be given equipment with which
(4) Spray Guns, for Manual Applications. -
MI L-C-46168 paints shall be applied only in ap-
plural components are to be applied. Problems
proved and qualified facilities. No application o'
may be encountered, i.e., required accuracy of
mixtures, pot life of mixtures and effects resulting
MI L-C-46168 shall be accomplished in open air. in
terior applications of MIL-C-46168 paint will be ac-
from non-adherence to prescribed application
complished using personal respirator masks and
procedures.
b.
Components of Application Equipment.
(1) Automated Systems (Robots). Such
systems include, but are not limited to, metering
Personal protective clothing, and
disposition thereof, should also conform
feed lines and tanks, regulators and computerized
to OSHA and NIOSH safety specifica-
automated components.
tions.
(2) Hoses. Because of friction losses in
(5) Paint Booths and Application Equip
hoses, it is essential that the proper sizes be used.
ment. No description or detail is provided for pain-
Do not use hoses longer than 50 feet except in the
ting facilities due to the variance of equipment
case of high pressure air hoses leading to the
and local conditions. Such equipment must,
regulator or tank. These may be a maximum of 150
feet for painting such areas as the tail surfaces of
through 8-8. For automated robotic equipment,
exceptionally large aircraft which are of consider-
manufacturer's instructions should be consulted.
able height above the ground. Extra lengths of
hose may be attached for this use but should be
(6) Paint Brushes. Paint brushes should
removed when no longer needed. The high pres-
be used during touch-up procedures in open air
sure air hose should have a minimum inside
when applying MI L-C-46168 paint. Consult section
diameter of 7/16 inch. No less than 3/8 inch ID
on touch-up procedures for details.
fluid hose should be used from the tank to the gun
and no less than 5/16 ID air hose from the regula-
3-10. PAINT SPRAY GUN TECHNIQUES.
tor to the tank and from the tank to the gun. Any
When manual spray applications are employed,
reduction in size or increase in length from the
techniques must be used which insure the most
forestated may produce unsatisfactory results,
uniform and proper dry thin coating. Spray guns
Air and paint hoses are furnished in various stand-
(and spray coatings) are designed to be used with
ard lengths, Determine the length required for use
certain spraying techniques. Quality of finish will
in a spray booth measuring the width of the booth
depend on how well these techniques are used.
and add two feet for the total required length of
Spraying techniques include the following:
the hose.
a.
Distance, Depending on the desired width
of the spray pattern. the gun IS held six to ten
Hoses should always be thoroughly
adjustments are correct. greater distance will
cleaned by purging and flushing with
result in dry spray or dusting and excessive over
solvent appropriate to the coating
spray. Holding the gun too close to the work W ill
material used. When the material is a
result in coatings which are too heavy and wiII
catalytic system (epoxy or polyure-
have a tendency to sag or run.
thane), this must be done immediately
after use and before the prescribed pot
Stroking. The essence of proper stroking
b.
life limit has been reached to prevent
is maintaining the same distance of the gun from
the material from gelling in the system.