Paasche A-BU-PL User Manual

A-BU

AUTOMATIC SPRAY GUNS

OPERATING INSTRUCTIONS AND REPLACEMENT PARTS

INSTRUCTIONS AND PARTS LIST A-BU-8/31/2011

Supersedes Instructions & Parts List A-BU-4/27/2010

WARNING: Spray materials may be harmful if inhaled or
allowed to come into contact with the skin or eyes. Consult
the product label and Material Safety Data Sheet supplied
for the spray material. Follow all safety precautions.
CAUTION: Well Venti late d Area Re quir e d t o r e move
fumes, dust or overspray. Secure airhose and fluid
hose wrench t i g h t f o r safety and t o pr e v e n t leaks .

M a x i m u m A i r P r e s s u r e 1 0 0 P . S . I .
M a x i m u m F l u i d P r e s s u r e 4 5 P . S . I .

DESCRIPTION:

The A-BU- Automatic Spray Gun, a medium duty air actuated
production spray gun, will cover a range of materials to include
light lacquers, abrasives or latex and corrosives.

AIR AND FLUID CONNECTIONS:

Air Inlet 1/4" N.P.T. (Female) and Fluid Inlet 3/8" N.P.T. (Male). A­BU- Automatic Spray Gun dimensions are 5-1/8"L x 2-1/4"D.
Packing Washers are treated leather and soaked in oil. For PTFE
Packings see page 3.

OPERATION:

1. Mount Gun in desired position.

2. Blow out all hoses before connecting to spray gun to
remove foreign particles.

3. Connect hose from air supply to air inlet fitting.

4. Connect fluid supply to fluid inlet.

5. Tighten all hose connections securely.

6. Adjust air pressure to desired amount at the air regulator.

7. Adjust fluid volume by turning the U-3178 Fluid Adjusting

Knob to the left (Increase) or right (Decrease).

NOTE: DO NOT USE AS A SHUT-OFF BY TURNING ALL

THE WAY DOWN, IT MAY SPLIT THE TIP.

TIP REPLACEMENT:

1. Turn off air pressure and fluid pressure.

2. Release needle pressure from the seat of fluid tip by
taking off the U-2686A Cylinder Cap Assembly. This will
relieve the spring pressure.

3. Loosen BU-12 Aircap Nut and remove Spray Head
assembly. Leave A-U-4 Needle in place.

4. Unscrew U- Tip. Place new tip in position.

5. When replacement is complete reassemble by reversing
the above procedure.

TROUBLE SHOOTING SPRAY PATTERNS:

A. A ROUGH OR STIPPLED FINISH is caused by low or

restricted flow of air pressure or too heavy materials being
applied with gun too close to surface.

B. A WET OR SAGGING FINISH is due to low air pressure or

restricted flow of air, material being too thin, or applied too
close to the surface.

C. A SPUTTERING SPRAY can be caused by air leaking into fluid

line, a loose fluid tip, a broken or split tip, lumpy material, a
clogged vent hole in cover of material cup, an air leak at fluid pipe
attached to inside of A.S.M.E. Tank cover, or a clogged paint
strainer. Sputtering may also be caused by worn packing
washers, or worn or scored needle.

TO CORRECT: Tighten tip securely or replace. Strain
material and clean strainer. Tighten fluid pipe in tank or
replace packings and needle in Spray Gun.

D. AN ARCHED FAN SPRAY PATTERN is caused by dried

material accumulated in one fan port of the fan aircap,
distorting the pattern.

TO CORRECT: Dissolve material inside fan port with
suitable solvent applied with a small brush.

NOTE: Never use wire or sharp instruments to clean
Fan Ports as permanent damage to the fan ports will
result in destroying uniformity of the fan pattern.

E. UNBALANCED FAN SPRAY PATTERN, heavy on one side,

may be caused by material collecting around outside of the
fluid tip and aircap, or by a loose aircap.

TO CORRECT: Remove aircap and clean fluid tip and
aircap with solvent then dry with air. Always be sure fan
aircap and aircap body are tightened securely.

MAINTENANCE:

Requirements of the A-BU- Automatic Spray Gun have been
reduced to a minimum. The leather packing washers should be
lubricated once a month with a light oil. Old packing washers
cause leakage of air or fluid and replacement should be made on
a regular schedule. PTFE Packings are available and are self
lubricating.

CLEANING:

Flush appropriate solvent through fluid passages of the Spray
Gun and wipe off the outside with a clean cloth. Never leave the
entire Spray Gun immersed as this will ruin leather packings.
Dirty aircaps and tips should be cleaned by soaking, then drying.

Paasche Airbrush Company

4311 North Normandy Avenue
Chicago, IL 60634-1395

Phone: [phone] • Fax: [phone]

Website: paascheairbrush.com
E-Mail: [e-mail]

F. A HEAVY CENTER in a fan pattern is caused by insufficient air

pressure at the fan port. Rough or shady edges are also
caused by low air pressure.

TO CORRECT: Increase air line pressure.

G. A SPLIT FAN SPRAY PATTERN, heavy on each end and light

in the center, is caused by excessive air pressure.

TO CORRECT: Reduce air pressure.

Printed in the U.S.A.

SPRAY HEAD COMPONENTS Pag e 2

Spray Heads for A-BU- Automatic Spray Guns are available in several different Styles, some of which are available with Stainless
Steel components. The C.F.M. requirements range from 2 to 14 C.F.M. @ 30 to 40 lbs. air pressure. NOTE: When either fluid
Tip or fluid Needle is worn and requires replacement, it is recommended that both items be changed for best results. All Tips
and Needles are made using 303 Stainless Steel. Carbide Tips and Needles are available for use with abrasive materials.

•

EXTERNAL- FAN PATTERN

•

Sizes: 2 or 4

•

Application: Application in tight areas - fast color change.

•

Fluid Viscosity: Light to Medium (2 to 6 C.F.M. @ 30 P.S.I.)

1. BNFA- Fan Aircap (Select Size)

2. BU-12 Aircap Nut

3. U- Stainless Tip (Select Size)

4. A-U-4 Stainless Needle

•

INTERNAL- ROUND PATTERN

•

Sizes: 2 or 4

•

Application: Fine lines, detailing stenciling and touch-up.

Latex, silver nitrate, acidic materials.

•

Fluid Viscosity: Light to medium (2 to 3.5 C.F.M. @ 40 P.S.I.)

1. BR-15- Aircap Body (Select Size)

2. BU-12 Aircap Nut

3. U- Stainless Tip (Select Size)

4. A-U-4 Stainless Needle

•

STAINLESS- INTERNAL- ROUND PATTERN

•

Sizes: 2 or 4

•

Application: Fine lines, detailing stenciling and touch-up.

Latex, silver nitrate, acidic materials.

•

Fluid Viscosity: Light to medium (2 to 3.5 C.F.M. @ 40 P.S.I.)

1. BSR-15- Stainless Aircap Body

2. BUS-12 Stainless Aircap Nut

3. U- Stainless Tip (Select Size)

4. A-U-3-1/32 Stainless Needle

•

STAINLESS- EXTERNAL- FAN PATTERN

•

Sizes: 0 only

•

Application: Corrosive materials.

•

Fluid Viscosity: Light to Medium (3 to 5 C.F.M. @ 40 P.S.I.)

1. BSF-15- Stainless St. Fan Aircap (Select Size)

2. BUS-12 Stainless St. Aircap Nut

3. U- Stainless Tip (Select Size)

4. A-U-4 Stainless Needle