Fasten The Door Bracket - Chamberlain 3280CM 1/2 HP Owner's Manual

INSTALLATION STEP 11

Fasten the Door Bracket

Follow instructions which apply to your door type as
illustrated below or on the following page.
A horizontal reinforcement brace should be long
enough to be secured to two or three vertical
supports. A vertical reinforcement brace should cover
the height of the top panel.
Figure 1 shows one piece of angle iron as the horizontal
brace. For the vertical brace, 2 pieces of angle iron are
used to create a U-shaped support. The best solution is to
check with your garage door manufacturer for an opener
installation door reinforcement kit.
NOTE: Many door reinforcement kits provide for direct
attachment of the clevis pin and door arm. In this case you
will not need the door bracket; proceed to Step 12.
SECTIONAL DOORS
1. Center the door bracket on the previously marked
vertical centerline used for the header bracket
installation. Note correct UP placement, as stamped
inside the bracket.
2. Position the top edge of the bracket 2"-4" (5-10 cm)
below the top edge of the door, OR directly below any
structural support across the top of the door.
3. Mark, drill holes and install as follows, depending on
your door's construction:
Metal or light weight doors using a vertical angle iron
brace between the door panel support and the door
bracket:
• Drill 3/16" fastening holes. Secure the door bracket using
the two 1/4"-14x5/8" self-threading screws. (Figure 2A)
• Alternately, use two 5/16" bolts, lock washers and nuts
(not provided). (Figure 2B)
Metal, insulated or light weight factory reinforced
doors:
• Drill 3/16" fastening holes. Secure the door bracket using
the self-threading screws. (Figure 3)
Wood Doors:
• Use top and bottom or side to side door bracket holes.
Drill 5/16" holes through the door and secure bracket
with 5/16"x2" carriage bolts, lock washers and nuts (not
provided). (Figure 4)
NOTE: The 1/4"-14x5/8" self-threading screws are not
intended for use on wood doors.
Fiberglass, aluminum or lightweight steel garage doors WILL
REQUIRE reinforcement BEFORE installation of door bracket.
Contact your door manufacturer for reinforcement kit.
Figure 1
Vertical
Reinforcement
Door
Bracket
Self-Threading
Screw
1/4"-14x5/8"
Figure 2A
HARDWARE
SHOWN
ACTUAL SIZE
Self-Threading
Screw
1/4"-14x5/8"
Figure 3
19
Header
Bracket
Door
Bracket
Location
HORIZONTAL AND VERTICAL
REINFORCEMENT IS NEEDED
Vertical FOR LIGHTWEIGHT GARAGE
Centerline DOORS (FIBERGLASS,
of Garage
ALUMINUM, STEEL, DOORS
Door
WITH GLASS PANEL, ETC.).
(NOT PROVIDED)
(Not Provided)
Vertical
Centerline
Bolt
of Garage Door
5/16"-18x2"
Door
UP
Bracket
Lock Washer
5/16"
(Not Provided)
Bolt
5/16"x2"
Vertical
Centerline
of Garage Door
Vertical
Centerline
UP
of Garage
Door
Self-Threading
Screw
1/4"-14x5/8"
Vertical
Reinforcement
Vertical
Centerline
of Garage Door
UP
Nut
5/16"-18
Figure 2B
Inside Edge
of Door or
Reinforcement Board
UP
Figure 4