Installing New Boat Rails: A Step-By-Step Guide

There are several types of rails that can be installed on a boat, including rub rails and hand rails. Rub rails are buffers that protect a boat from abrasion and mild bumps, whereas hand rails are safety features that provide support for passengers. Before installing new rails, it is important to measure the boat and plan the placement of the rails and their fasteners. When removing old rails, it is important to take care not to damage the boat's surface. Different types of rails will require different tools and techniques for installation.

Choosing the right material for your rails

When choosing the right material for your boat rails, there are several factors to consider, including durability, aesthetics, and cost. The most common materials for boat rails are flexible vinyl, semi-rigid vinyl, rigid vinyl, stainless steel, and aluminum.

Flexible vinyl is the most affordable option and offers good durability. It is flexible, making it easy to install, and has impact-absorbing properties. However, it may not provide the same level of aesthetics as other materials. Semi-rigid vinyl offers a balance between flexibility and rigidity, making it a popular choice for boat owners who want a combination of durability and ease of installation.

Rigid vinyl, also known as hard vinyl, is known for its durability and impact resistance. It is a popular choice for boat owners who require a strong and sturdy rail that can withstand harsh conditions. Stainless steel is an extremely durable material that provides a sleek and modern look. It is resistant to corrosion and has a high strength-to-weight ratio, making it ideal for boat rails. However, stainless steel is more expensive than other materials.

Aluminum is another popular choice for boat rails due to its lightweight and durable properties. It is strong, impact-resistant, and corrosion-resistant, making it suitable for saltwater environments. Aluminum rails are also easy to install and maintain.

Other factors to consider when choosing the right material for your boat rails include the diameter and loading capacity of the rails. For example, heavy-duty 316 stainless steel boat rail fittings are designed to withstand offshore conditions and provide a secure grip.

Additionally, it is important to measure your boat accurately to ensure you order enough rail material. As a general rule of thumb, you should add your boat's length to its beam and then double the sum to ensure you have enough material to complete the installation.

Removing the old rails

Removing the old rub rail is a crucial step in the process of installing a new one. Here is a detailed guide on how to go about it:

Begin by locating the beginning and end pieces of the rub rail, typically found at the bow or stern of the boat. Using a slotted screwdriver, carefully pry off the insert and gently pull it out of the track. This will expose the fasteners, which can be screws or rivets. If you encounter screws, simply unscrew them, but if you find rivets, you will need to drill them out using a bit of equal or slightly smaller size. This process will help you detach the rub rail from the boat's surface.

Once the rub rail is removed, it's important to clean the surface and remove any excess sealant or residue. You can use a scraper or a suitable solvent to ensure the surface is clean and ready for the new installation. After cleaning, it's crucial to fill the holes left by the previous fasteners. Use an appropriate sealant or epoxy filler to fill and seal these holes. This step is important to create a smooth and even surface for the new rub rail.

Before proceeding, it's a good idea to mark the locations of the previous screws or fasteners with pencil marks or masking tape. This will help you avoid drilling into the same spots later, ensuring a more precise installation. Additionally, if your old rub rail had end caps, make sure to remove them as well.

Take note of the height of your previous rub rail. It is recommended to match this height as closely as possible with the new rail. If you are unsure or cannot find an exact match, it is generally better to go slightly taller with the replacement. This ensures that your boat's hull remains adequately protected.

Finally, take some time to inspect the old rub rail and how it was attached. Look for any specific features or installation methods that might impact the installation of the new rail. For example, if the old rub rail's ends were clipped together on the bow, consider avoiding that design and opt for a different configuration to improve the overall strength of the installation.

Measuring the boat for the new rails

Measuring your boat for new rails is a crucial step in the installation process. Here are some detailed instructions to ensure accurate measurements:

Firstly, it is important to consider the type of rail you plan to install. For example, if you are installing a rub rail, you need to ensure that the new rail is at least the same height as the old one to avoid exposing parts of the hull. It is recommended to go slightly taller if you are unsure. The rub rail material is also a factor to consider, with options including flexible vinyl, semi-rigid vinyl, rigid vinyl, stainless steel, and aluminum. Each material has its own set of installation considerations.

Now, let's move on to the specific measurements. You will need to measure the length of your boat, the beam (width), and decide on the desired length of the rails. A good rule of thumb is to add the length and beam of your boat and then double that sum to ensure you have enough rail material. This calculation accounts for the curves of your boat and ensures you have sufficient material for a neat installation.

When measuring for the placement of the rails, mark the locations for the fastener holes every 6 to 8 inches around the boat. This will ensure that you can drill accurately when installing the rails. It is also important to consider the placement of the end caps and any curves or bends in the rails, especially at the corners or the bow. If you are working with a coiled rub rail, uncoil it and mark the center point, ensuring that the lip of the rail will be at the bottom. Place this center point against the center of the bow, and then stretch the material to the desired length.

If you are installing handrails, the process is slightly different. Measure the necessary lengths along the cabin top and decide on the number and spacing of the legs or base blocks. A good starting point for leg spacing is 12 inches, and you can adjust from there based on the overall length of the rail. For example, for a 6-foot 6-inch rail, you could choose a spacing of 11 inches for eight legs or 11.5 inches for seven legs. Aesthetic preferences and the width of the rail will also play a role in determining the optimal leg spacing.

Finally, decide on the height of the handrails, which can range from 2.25 inches to 3 inches. The depth of the rail should be at least 1.5 inches to provide a secure grip and prevent fingers from getting caught. The area of the base of the legs should be between 1.25 and 3 square inches. These measurements will ensure that your handrails are both functional and sturdy.

Installing the new rails

The first step in installing new rails on your boat is to measure the necessary lengths and decide on the number and spacing of the legs or base blocks. The spacing can vary from 6" to 15", but a good starting point is 12". For example, if you need a 6' 6" rail, you could have seven legs with 11" spacing or eight legs with 11" spacing.

Once you've determined the spacing, you need to decide on the profile and cross-section shape of the rails. This is an aesthetic choice, but you should note that angular profiles, such as profile II in the illustration, are best made by gluing separate leg sections to the rail, which saves lumber but increases construction time. After deciding on the profile and cross-section, choose a height between 2" and 3" for the rails, ensuring that the leg depth is at least 1.5".

The next step is to decide whether to cut the rails from one piece or make them from separate pieces. This decision is partly controlled by the chosen cross-section. If you've selected cross-section 1 or 2, you'll need to build up the rails from separate pieces. For cross-sections 3 or 4, you have the option to cut the rails from one piece or build them up from separate pieces. One-piece construction is quicker but wastes more lumber, while built-up construction takes longer but uses less lumber.

If you choose to build up the rails, start by cutting the long rails and the legs (if separate) from strips of wood. Then, glue the legs to the rails using epoxy, plastic resin, or resorcinol glue. Epoxy is a good choice for beginners as it fills gaps well and can be used on teak if you carefully wipe the wood with acetone first. Clamp the pieces together or fasten them with screws or ringed boat nails while the glue sets.

For rounded profiles, make a cardboard template of the transition curves between the rail and the base to ensure that each curve is the same. Use the template to carefully blend the curves into the straight lines of the legs.

Once the rails are built or cut, shape the sections using a plane, Surform, rasp, and sandpaper to achieve the desired shape. If you have an ellipsoidal or heavily rounded rail section that meets a leg, feather the curved rail section into the leg top to retain a rectangular horizontal cross-section for the leg base.

Finally, attach the rails to the boat with a bolt through each leg and the deck, perpendicular to the deck. Use stainless steel, flat-head bolts with a minimum diameter of 1/4". Counter for the bolt head and use wood plugs in the rails, along with plywood backing blocks about 2" square under the decks. Finish the rails with varnish, paint, or oil.

If you're installing a rub rail, follow these steps:

• Remove the old rub rail by prying off the insert with a slotted screwdriver and pulling it out of the track. Then, remove the fasteners (screws or rivets) and scrape off any excess sealant.
• Fill the holes left by the fasteners with sealant and let it cure before drilling new holes. New holes should be drilled every 6"-8".
• Choose a rub rail that is at least the same height as the old one to avoid exposing parts of the hull. You will need enough rub rail to cover twice the length of your boat plus the beam plus at least two feet.
• Start installing the new rub rail at the bow or the stern, drilling holes through the rail and the boat and securing it with fasteners and sealant.
• Continue around the boat, using a heat gun to soften the rail at corners or the bow to help it take the bend. Overlap the ends of the rub rail by one-eighth of an inch and secure with screws.
• Drill pilot holes and install mounting screws along the length of the rub rail, working from the bow aft. Use marine sealant on the screws before driving them into the holes.
• Install the insert by squeezing or tapping it into the track, using liquid soap or a heat gun to help move it into place if needed.
• Trim the rub rail/insert and install the end caps using a razor knife or pruning shears.

Finishing and sealing the rails

Now that you've removed the old rub rail, cleaned the surface, and filled in the old screw holes, it's time to seal the joint between the deck cap and the hull. Choose a sealant that is suitable for marine use and apply it to the joint, following the manufacturer's instructions for proper application and drying time.

Once the sealant is dry, it's time to install the new rub rail. If your rail came in a kit, follow the manufacturer's instructions for installation. If you're using a separate rail, mark the location of the screws with pencil marks on the gunwale to avoid drilling into previous spots. Use a power drill to create pilot holes through the pre-drilled holes in the rub rail. Apply marine sealant to the screw threads before driving them into the holes with a power driver.

As you work your way around the boat, you may need to use a heat gun or hair dryer to soften the rub rail material and help it conform to the shape of the boat. At the transom, you may need to trim the rub rail to fit neatly. Use a razor knife or pruning shears to cut the rail, then peel back the insert and install the final screw. Reinstall the insert and position the end cap. Use the mounting holes as guides to drill pilot holes, then secure the end cap with stainless-steel screws.

For boats without notched transoms, such as inboards, sterndrives, or outboard brackets, you'll need a different type of finishing piece, such as a rub-rail splice cap. This will tie together the two ends of the rub rail that meet in the middle of the transom. Follow the manufacturer's instructions for proper installation.

Finally, use a gloved finger to smooth out any excess sealant that has squeezed out from behind the rub rail. Pull up the masking tape and clean any remaining residue. Your new rub rail is now installed and sealed!

Frequently asked questions