Craftsman 1/2 HP GARAGE DOOR OPENER 139.53978SRT - Manual (Page 24)

Installation Step 11
Fasten Door Bracket
Follow instructions which apply to your door
type as illustrated below or on page 25.
To prevent damage to steel, aluminum,
fibergiass or giass panei doors, always
reinforce the inside of the door both verticaily
and horizontaily with an angle Iron.
A horizontal brace should be long enough to be secured to 2 vertical supports. A vertical brace should
cover the height of the top panel.
The illustration 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. ^
• Center the door bracket on the previously marked
vertical guideline used for the header bracket
installation.
Note the correct UP placem ent, as
stam ped inside the bracket.
• Position the bracket on the face of the door within
the following limits:
A) The top edge of the bracket 2"-4" below the top
edge of the door.
B) The top edge of the bracket directly below any
structural support across the top of the door.
• Mark and drill 5/16" left and right fastening holes.
Secure the bracket as shown in Figure 1 if there is
vertical reinforcement.
if your installation doesn't require vertical reinforce­
ment but does need top and bottom fastening holes
for the door bracket, fasten as shown in Figure 2.
Figure 2
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