Saab 95 1967, Руководство по обслуживанию

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TOUCH'UF Ann; In.- Il‘v-
General
For all touch-up or refinish jobs, use synthetic stoving or
airdryjng enamel of the same quality type as that for the
original paintwork.
For perfect results, it is essential that the premises in
which the work is to be done, Le. the paintshop, be kept
absolutely free of dust. It should also be free of drafts
and must naturally not be used as a means of access to
other departments. The floor should be kept thoroughly
damp while spraying. A paint job ruined by dust cannot
be restored by polishing —— flatting and respraying will be
necessal'Y-
Body finishing
Before undertaking any partial refinishing, always spray
a test area to check that the shade used is identical with
the color of the parts that are not to be refinished. Any
deviations must be corrected by toning the paint. The
painting job involves the following operations:
Removal of rust and old paint
Rubbing down
Cleaning with a solvent
Priming of bare metal surfaces, for instance with wash
primer
Filling, if necessary
Flatting
Application of intermediate coat, for instance Surfacer
or Non Sanding, if necessary
Flatting, if necessary
Finishing
Air-drying, stoving with infra-red radiant heat or in a
drying oven, depending on the type of enamel used.
Cleaning
If the old paintwork shows defects such as cracking, pit-
ting due to the impact of flying stones, etc., apply a Paint
remover or flatten down to the bare metal. After removal
of the old paintwork by one or the other of these methods,
degrease the metal with spirit, thimmer or some other suit-
able solvent. In principle, the same procedure should be
“Sed even if the old paintwork has merely been rubbed
°°Wh instead of being removed. Realign any distorted
Banals and grind, for instance with a disc grinder, ‘f neces-
sary, before flattening with wet abrasive paper P 490-
Finally, reclean the parts with spirit or cellulose thinner.
Th°'°U9hness in this respect is vital to 900d adhesnon.
Priming
Coat all bared metal surfaces with primer. The drying
time and temperature for oven-drying or air-drying should
he as prescribed by the paint suppliers. An infra—red radia-
no" lamp may also be used for drying, but care must be
taken to keep it at a distance of not less than 16 in. (40
om) from the metal. After drying, fill as necessary, apply-
"‘9 the Way in thin layers and allowing the stipulated
drYihQ time for each layer before the next application.
Rubbing down
Rub down the primed and filled surface with wet abra-
sive paper P 400 and then with grade P 600. After remov-
ing all water, rewash the surfaces with spirit or cellulose
and wipe with a piece of gauze drenched in slow drying
varnish (tack-ragging).
Equipment and procedure for refinishing
A. Stoving touch-up enamel
Oven:
A convection oven with an air temperature of 194—2120F
(90—100°C) is needed. A radiation oven can be used, and
in this case the metal temperature should be about 176°F
(80°C). It is important for the air temperature to be even
throughout the oven and for the temperature to be conti-
nuously checked. For this purpose, it is appropriate to
use, for example, a calibrated max. and min. thermome-
ter or a thermo-element with a compensator. Only this
latter measuring method can be used to check the plate
temperature.
Enamel:
Hardener must be added to the touch-up paint used in
the amount stipulated by the paint supplier. The enamel
can be sprayed either hot or cold, and the viscosity
should be adjusted accordingly with the thinner recom-
mended by the paint supplier to the following:
Hot spraying — viscosity approx. 35 sec.
Cold spraying —- viscosity approx. 21 sec.
Measure the viscosity with a beaker according to the
method described in the Saab standard 860 at a tempe-
rature of approx. 68°F (20°C).
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