LiftMaster 3255 3255 Manual - Page 20

ONE-PIECE DOORS Please read and comply with the warnings and reinforcement instructions on the previous page. They apply to one-piece doors also. • Center the door bracket on the top of the door, in line with the header bracket as shown. Mark either the left and right, or the top and bottom holes. • Metal Doors: Drill 3/16" pilot holes and fasten the bracket with the 1/4"-14x5/8" self-threading screws provided. • Wood Doors: Drill 5/16" holes and use 5/16"x2" carriage bolts, lock washers and nuts (not provided) or 5/16"x1-1/2" lag screws (not provided) depending on your installation needs. NOTE: The door bracket may be installed on the top edge of the door if required for your installation. (Refer to the dotted line optional placement drawing.) HARDWARE SHOWN ACTUAL SIZE Self-Threading Screw 1/4"-14x5/8" Header Wall 2x4 Support Finished Ceiling Header Bracket Door Bracket Optional Placement of Door Bracket Vertical Centerline of Garage Door HORIZONTAL AND VERTICAL REINFORCEMENT IS NEEDED FOR LIGHTWEIGHT GARAGE DOORS (FIBERGLASS, ALUMINUM, STEEL, DOORS WITH GLASS PANEL, ETC.). (NOT PROVIDED) Door Bracket Nut 5/16"-18 Door Bracket For a door with no exposed framing, or for the optional installation, use lag screws 5/16"x1-1/2" (Not Provided) to fasten door bracket. Self-Threading Screw 1/4"-14x5/8" Top of Door (Inside Garage) Top Edge of Door Optional Placement METAL DOOR Lock Washer 5/16" Top of Door (Inside Garage) Top Edge of Door Optional Placement Carriage Bolt 5/16"x2" (Not Provided) WOOD DOOR 20