Formable ATL6 perimeter
The custom ATL6 extrusion forms the hardtop perimeter and can be shaped to suit the required hardtop outline.
Atlantic Towers® composite hardtop system
ATL6 Hardtop Construction
A formable aluminum perimeter, welded roof structure, and lightweight fiberglass panel combine to create a composite hardtop shaped for the required perimeter and installation.
- Frame
- One-piece welded aluminum
- Perimeter
- Formable ATL6 extrusion
- Top panel
- Lightweight fiberglass
Structural foundation
Shape first, reinforce second
The ATL6 perimeter is formed to the required hardtop shape. Rectangular carlins are then added from side to side to reinforce the roof and complete the welded aluminum structure.
Rectangular carlins
Side-to-side roof reinforcing beams—called carlins in nautical terminology—join the perimeter to create the supporting frame.
One-piece welded frame
The perimeter and reinforcing structure are assembled as a welded aluminum frame before the fiberglass panel is fitted.
Equipment and enclosure planning
Two mounting surfaces built into the frame
An ATL4 extrusion normally runs the length of the hardtop centerline for radar, searchlights, hailers, and other mounted equipment.
The hardtop leading edge is typically shaped to follow the boat's windshield or flybridge cowl. This allows a clear-plastic enclosure, supplied by others, to fit almost flat between the windshield and the new hardtop.
Fiberglass panel installation
Bonded, fastened, sealed
The fiberglass panel becomes part of the completed structure through a four-stage fitting and fastening process.
- 01
Cut and fit
A thin, flexible, lightweight fiberglass panel is cut to fit the recess in the top of the ATL6 extrusion.
- 02
Prepare and bond
After fitting, the panel is washed, then bonded to the carlins and center reinforcement with 3M industrial adhesive on a foam core.
- 03
Secure the perimeter
Closely spaced stainless-steel screws fasten the fiberglass into the perimeter notch.
- 04
Seal and conceal
RTV silicone rubber seals the edge and completely hides the perimeter screws.
Custom shape, engineered structure
Plan the hardtop around the boat and its equipment
Share the boat model, windshield or cowl geometry, enclosure plans, and equipment list so Atlantic Towers® can evaluate a custom ATL6 hardtop configuration.