Bomar hatches are renowned in the marine industry for their durability, watertight integrity, and long-lasting performance. Whether used on luxury yachts or commercial vessels, these hatches are engineered to meet the high demands of marine environments. For boat owners and professionals involved in marine maintenance or boatbuilding, understanding the correct procedures for removing, cutting, and installing Bomar hatches is essential for ensuring safety, functionality, and longevity. This article provides a step-by-step explanation of the installation process based on detailed instructions from Bomar’s technical documentation and installation guides.
Key Installation Considerations
Before beginning the installation process, it is important to understand the general requirements and limitations that apply to Bomar hatches:
- Deck Thickness and Fitment: Bomar hatches can be installed on decks of varying thicknesses, but care must be taken to ensure that the hatch’s lower frame does not intrude into the cabin if the deck is particularly thin.
- Trim Kits and Cut Outs: If a trim kit is being installed, the cut-out size in the deck must be increased by 3 mm to accommodate the trim. This ensures a proper fit and prevents damage to the deck or hatch frame.
- Opening Mechanism: Hatch lids must open beyond 90 degrees to allow for secure mounting to the deck. If the hatch cannot open fully due to structural obstructions, it may not be possible to install it correctly.
- Support and Stability: When the hatch is fully open, the lid should rest near the edge with the handles providing support. If the lid is supported near the hinges instead, the leverage may cause the hatch to be damaged over time.
- Portlight Considerations: Portlights also have specific requirements for deck thickness. If the hull thickness exceeds the recommended range, the portlight may have restricted opening. Appropriate fastenings must be selected based on the deck thickness, and additional fastenings may need to be ordered if those included with the portlight are not suitable.
Hatch Removal Instructions
Removing an existing hatch requires careful handling to avoid damaging the deck or the surrounding structure. The process outlined in the technical documentation emphasizes the importance of using proper tools and techniques to ensure the hatch can be safely removed and replaced.
- Preparation with a Wood Bridge: A wooden bridge should be placed over the corner of the hatch frame to protect the deck. To prevent damage, cardboard or carpet should be placed under the feet of the bridge. A second piece of wood should be positioned inside the boat, aligned with the same corner of the hatch frame. A miter joint may be necessary to ensure this piece only contacts the hatch frame and not the deck.
- Lifting the Frame: A G-clamp is used to lift the second piece of wood toward the bridge. This action helps to begin separating the lower frame from the deck.
- Cutting the Sealant: As soon as the frame is slightly lifted, a sharp, thin-bladed knife should be used to cut through the bedding compound between the frame and the deck. This step is crucial to ease the removal process and prevent delamination.
- Clearing Old Sealant: Before installing the new hatch, all old sealant must be removed from the area. Any existing fastening holes should also be filled to prevent future water ingress or structural weaknesses.
These steps ensure that the hatch can be removed without damaging the surrounding deck or internal structure of the boat.
Hatch Installation Process
Once the old hatch has been removed and the deck prepared, the new hatch can be installed following a precise sequence of steps to ensure a secure and watertight fit.
Marking and Cutting the Deck
Before cutting the deck, the area should be checked to confirm it is a flat surface with minimal variance (±1 mm). A template is typically provided with the hatch to help mark the cut-out dimensions accurately. If a trim is being installed, the cut-out should be increased by the specified amount to accommodate the trim.
- Marking the Cut Line: The template is placed over the back of the hatch and taped to the deck to mark the cut line.
- Cutting the Aperture: A hole is drilled for the jigsaw blade on the waste side of the cut line. A jigsaw is then used to cut through the deck. Care must be taken to avoid cutting into power cables, gas pipes, or other services.
- Headlining Considerations: It may be necessary to cut or remove the headlining to complete the aperture. In some cases, a hole cutter that matches the corner radii may be used for the corners.
Test Fitting and Alignment
Before applying sealant, the hatch should be test-fitted to ensure it aligns correctly with the cut-out. This step is crucial to confirm the hatch is properly sized and positioned.
- Clamping the Frame: The outer frame of the hatch is clamped against the deck using the inner frame inside the boat.
- Marking Fixing Holes: With the hatch in place, the lower frame fixing holes are marked. The hatch is then removed from the deck, and the fastening holes are drilled.
- Fastening the Frame: The hinges should be through-bolted, while self-tapping screws can be used for the remainder of the frame. This ensures a secure and stable installation.
Sealing and Final Installation
After the hatch is properly aligned and the fastening holes are drilled, the sealing process begins. This step is critical to maintain the hatch’s watertight integrity.
- Applying Sealant: A generous bead of bedding compound is applied all around the frame where it contacts the deck. This helps to create a watertight seal and prevents water ingress.
- Sealing Fastening Holes: Sealant is applied to both sides of the fastening holes on the hatch frame. If the hatch is replacing an existing one, any old fixing holes should be filled with sealant.
- Refitting the Hatch: The hatch is then refitted to the deck, and a small amount of bedding compound should be forced out of the gap between the frame and deck. The lower frame is then fastened to the deck using the appropriate hardware.
- Cleaning Excess Sealant: Any excess bedding compound should be cleaned up to ensure a clean and professional finish.
This process ensures that the hatch is securely installed and properly sealed against water and environmental damage.
Portlight Installation Considerations
While the focus of this article is on hatch installation, the same attention to detail and adherence to specifications is required for portlights. Bomar portlights are engineered to provide clarity, strength, and watertight performance in all conditions.
Marking and Cutting the Aperture
- Template Use: A template is used to mark the cut-out dimensions on the deck. The template is placed over the back of the portlight and taped to the boat to mark the cut line.
- Safety and Precision: Safety equipment such as power breakers and safety glasses should be worn. A hole is drilled for the jigsaw blade on the waste side of the cut line, and the aperture is cut through the deck using a jigsaw. Care must be taken to avoid cutting into power cables, gas pipes, or other services.
Test Fitting and Alignment
- Clamping the Frame: The portlight is test-fitted by clamping the outer frame against the deck using the inner frame inside the boat.
- Sealant Application: Before applying sealant, the portlight is clamped ringed and test-fitted to ensure a proper fit. If replacing an old portlight, any old fixing holes should be filled with sealant.
Final Installation
- Fastening the Portlight: The portlight is fastened in place using the appropriate hardware. The sealant is applied to both sides of the fastening holes.
- Clamping and Sealing: The portlight is clamped in place, and a generous bead of bedding compound is applied around the frame to ensure a watertight seal.
Technical Specifications and Design Features
Bomar hatches and portlights are built using high-quality materials such as marine-grade aluminum, stainless steel, and acrylic. These materials are selected for their durability, resistance to corrosion, and ability to withstand harsh marine environments.
Material and Construction
- Aluminum and Stainless Steel Hardware: Bomar hatches are equipped with aluminum and stainless steel hardware, which provides strength and longevity.
- Acrylic Lenses: Heavy-duty acrylic lenses are used for clarity and impact resistance.
- Anodized Frames: The frames are anodized to enhance durability and prevent corrosion.
- Heavy-Duty Hinges: The hinges are designed to support the weight of the hatch lid and ensure smooth operation.
- Quick-Acting Tie-Down Dogs: These dogs allow for quick and secure closure of the hatch, even in rough conditions.
- Molded Trim Rings and Screens: Molded trim rings and sewn screens are available on select sizes to enhance the aesthetic and functional aspects of the hatch.
Performance and Safety
- Watertight Integrity: Bomar hatches are designed to maintain a watertight seal, even in the most challenging marine environments.
- High Load Tolerance: The hatches are built to handle high loads, making them suitable for commercial and offshore operations.
- Serviceability: The design allows for easy maintenance and replacement of parts, ensuring the hatch can be serviced without the need for complete removal.
Compatibility and Customization Options
Bomar offers a wide range of customization options to meet the specific needs of boat builders and owners. These include:
- Inside/Outside Opening: Some hatches can be configured to open from either the inside or the outside, providing greater flexibility in design and usage.
- Powder Coating: For added protection against the elements, hatches can be powder-coated in a variety of colors.
- White Acrylic Lens: A white acrylic lens is available for those who prefer a different aesthetic or lighting effect.
- Trim Ring Options: Trim rings are available in both extruded and molded styles, and can be specified in black or off-white. Black is the standard option.
These customization options allow boat builders and owners to tailor the appearance and functionality of their hatches to suit their specific needs.
Conclusion
Bomar hatches are a trusted choice in the marine industry due to their superior construction, watertight integrity, and long-lasting performance. Proper installation is essential to ensure these hatches function correctly and provide reliable service over time. By following the detailed instructions provided in the technical documentation, boat owners and professionals can confidently remove, cut, and install Bomar hatches with precision and care.
Careful attention to deck thickness, trim kits, and sealing procedures is crucial to the success of the installation. Whether replacing an old hatch or installing a new one, adhering to the manufacturer’s guidelines ensures the hatch will perform optimally in all conditions. With the right tools, materials, and techniques, Bomar hatches can be installed with confidence, providing a secure and durable solution for any marine vessel.