Paasche Airbrush AB-PL - Manual (Page 3)

Paasche AB (Fine Art) Airbrush Instructions and Parts List Page 3
SHAPING THE NEEDLE (Continued from page 2):
The other curve of the needle (top view) is the one that
varies most from airbrush to airbrush. Again, there should
be a gradual curve, with a straight section at the tip of the
needle. The idea is to curve the needle completely under
the lip of the needle guide (if the needle rides at the edge
of the lip, the needle will not stay in place as it oscillates),
and at the same time for the tip of the needle to ride
nearly parallel with the edges of the slot in the needle
bearing. It is normal for the tip of the needle to sit at a
slight angle in the needle bearing—with the curve in the
needle, you can’t help it. But this angle should be
minimized, to keep the needle from binding in the needle
bearing.
ADJUSTING THE COLOR CUP:
The color cup is clamped into the color cup support by
tightening the screw on the front side of the support. To
determine how far the color cup should project from the
support, first run the Finger Lever Adjusting Screw out
(counter-clockwise) until there is just a “hair’s breadth”
remaining between the butt end of the needle and the end
of the slot in the walking arm. This finger lever position is
called the “farthest forward rest position.”
Now slide the color cup in or out of the support until the
tip of the needle comes to the end of the slot in the
needle bearing but does not project from it. Attach the AB
to your air compressor and start the needle moving with
the finger lever in the “farthest forward rest position”
(push down the lever but do not pull back). Slide the color
cup out until the needle does not project from the
bearing—you now have the correct color cup position for
the “farthest forward rest position.” Note: The rapidly
moving tip is easier to see against a white background.
The color cup can also be partially rotated to allow you
to spray onto a surface more or less horizontally. You will
notice as you rotate the color cup, the position of the
needle bearing changes, necessitating a readjustment of
the airblast tube and in a few instances even a
recurvature of the needle. For this reason you will
probably want to find one position for the color cup which
is comfortable for you and then stick with it. The amount
of tilt is limited, from a position in line with the power
wheel housing to about 30 degrees below this line.
AIR VALVE PARTS REPLACEMENT:
This is rarely necessary, but these parts can be
replaced fairly simply. Unscrew the valve nut and remove
the spring plunger, and washer in that order. Use a small
stiff wire with a slight hook bent into the end of it to fish
out the washer. Then place a new washer on the plunger
and insert the plunger and washer together. To avoid
compressing the springs too far, screw the valve nut in
only until it is slightly below the level of the air valve
casing.
ADJUSTING THE AIRBLAST TUBE:
Check that the color cup is properly positioned as
described above. With pliers loosen the locknut where the
airblast tube attaches to the body of the airbrush. Now
rotate the airblast tube, screwing it in (counter-clockwise)
or out (clockwise) until the airblast jet is about 1/64 inch
from the end of the needle bearing. Now with the air
turned off pull back the finger lever so that the needle is
pushed out in front of the airblast jet. The distance from
the needle to the tip of the jet should be about 1/64 inch.
Very carefully you may bend, if necessary, the airblast
tube where it enters the locknut and arches to the body of
the airbrush to accomplish this second adjustment. Do
not bend at the elbow of the airbrush tube or in front of
the elbow for two reasons: (1) curved tubing such as the
elbow in the airblast tube is inherently more brittle and
tends to crack if leverage is applied to it, and (2) there is a
soldered joint where the stipple adjuster is attached to the
elbow, which may break if pressure is applied.
Finally set the airblast tube so that the needle, when
extend ed, passes through the center of the airstream
from the airblast jet—that is, as you sight down the hole in
the airblast jet, the needle should cross the center of that
hole. If the needle is off center, you will get a stippling
effect, and for some applications you may wish to set the
airblast tube in this way purposely.
The “AB” Airbrush is not suitable for use with alcohol or
lacquer colors. Any water color, opaque or oil can be used with
brilliant results.
See Page 4 for AB Replacement Parts and Parts Numbers.