Star Tech Journal

S~R-TECH _ _ _ _ _ _ _ _ _ 3
Mechanical Maintenance Tips
for Williams' Pin Games
MECHANICAL MAINTENANCE
General Switch Blade Adjustments
There are different types of switch blades used in any
game. Various lengths, thickness and forms are selected
characteristics to satisfy specific operational conditions
(bounce, current capacity, etc.). For this reason, always
use a blade of the same type for replacement. Basic
guidelines for switch adjustments follow:
1. Never kink or bend a blade sharply; adjust with a
sweeping, bowing motion with a switch adjusting tool
or duckbill pliers.
2. Before adjusting any switch, check that the screw
holding the switch stack is tight. This is recommended
because spacers in the switch stack occasionally
shrink causing a poor adjustment.
3. Except when otherwise indicated, blade type switches
should have at least 1 /32 inch between open contacts
and have at least a 1 /32 inch follow-thru when closed.
4. First adjust the actuating blade for approximate
gapping and the other blade for the final gap and for
follow-thru.
Contact Care
1. Switch contacts should be cleaned only when they
cause a malfunction.
2. For flipper button and flipper end-of-stroke switches,
remove tarnish with a contact file and then burnish.
Severely burnt contacts should be replaced as an
assembly.
3. All other types of contacts MUST NOT be filed or
burnished.
4. To clean contacts of other blade type switches, close
the contacts on a clean piece of paper about the
thickness of a busines card and wipe gently until the
contacts are clean.
5. For drop target switches, remove the two screws
securing the circuit board. Clean the circuit board
plating with a rag and pencil eraser. Carefully clean
the wiper contacts with a burnishing tool- do not use
an abrasive.
Rollover Switches
Rollover Switches are activated by a wire form or button
which is actuated by the ball.
1. Before adjustment, make sure that the wire form
rollover is centered in the slot or that the switch blades
are positioned under the button actuator.
2. Adjust the long blade (closest to the playfield) to hold
the rollover up. Check this condition with the playfield
lowered.
3. With the playfield up, adjust the short blade for 1 /16
inch contact gap.
4. The backup blade (which prevents vibration) should
be adjusted parallel to and just barely in contact with
the shorter blade.
Tilt Switches
1. To make the plumb bob tilt more sensitive, raise the
plumb bob on the shaft. To make it less sensitive,
lower the bob on the shaft.
2. To make the ball roll tilt more sensitive, raise the
assembly at the front pivot slot. To make it less
sensitive, lower the assembly at the front pivot slot.
3. The slam tilt and playfield tilt switches are adjusted by
forming the switch blades.
Flippers
Flippers are controlled by the flipper pushbuttons at each
side of the cabinet. Each coil consists of two windings: a
pull-in winding and a lighter gauge hold-in winding. The
hold-in winding is normally bypassed by a closed switch.
The pull-in winding produces a strong stroke. However, if
this winding were to remain energized by the player it
would overheat. To reduce this high current, the hold-in
winding is put in series with the pull-in winding by
opening the end-of-stroke switch.
1. Adjust the long blade so that it is moved by the flipper
pawl assembly for about the last 1/s inch of movement.
2. Manually depress the plunger fully and adjust for
approximately 3/32 inch gap.
3. There should be about 1 /32 inch follow-thru with the
plunger released.
4. NEVER LUBRICATE the plunger.
5. For weak or sluggish flipper action, check for all the
following:
a. Dirty, pitted, or misadjusted flipper button or end of
stroke contacts.
b. Worn out coil sleeves.
c. Loose or broken bushing.
d. Worn out fiber links.
e. Weak or broken return spring.
f. Broken flipper shaft.
g. Coil loose.
h. Loose screws.
i. Flipper binding on plc!yfield.