Buying an Aluminum Fishing Boat

7 Things to Know When Buying an Aluminum Fishing Boat

Thinking of buying an aluminum fishing boat?

All of the major manufacturers include specifications about the boats that they make, and customers are often uncertain about the meaning of these specifications. In the video “Understanding Aluminum Welded Boats,” (above) Mike Hudson, principal dealer at Port Boat House, helps shed light on these specifications.

Using a North River Seahawk Offshore as a reference boat, Mike shares insights, based on 30 years of experience in the industry, about some of the key specifications and characteristics that you should look for when considering the purchase of an aluminum welded fishing boat.

Aluminum Thickness and Alloy Type
According to Mike, two important specifications when considering an aluminum welded boat are the thickness of the aluminum used throughout the boat. The other is the type of aluminum alloy used, and where it’s used. Hull thicknesses on aluminum boats can vary from 1/4 inch (.250) to 1/8 inch (.125). For example, a North River Seahawk OS has ¼” hull plate from the stern of the boat to the bow including the transom and engine bracket sides. The engine bracket aft plate is 3/8”. The thickness of aluminum used on the boat’s sides is also important. On the North River Seahawk OS, the sides are made of .190” aluminum plating. Tensile strength is a factor of the aluminum alloy used, with 5086 aluminum being the strongest. North River uses 5086 for both the bottom and sides of these boats. 5086 alloy is also more corrosion resistant.

Why are these specifications important?

The bottom line is that aluminum boats with a stronger structure, based upon using thicker aluminum and the strongest alloys, will flex less on the water, greatly reducing the risks of cracking.

Bottom Width is More Important than Beam Width
When considering the bottom width and the beam width measurements of an aluminum boat, it’s important to understand that the bottom width is the more important measurement of the two. The beam width is the measurement of the width from the top of the gunwale on one side, to the top of the gunwale on the opposite side. Bottom width is the outside measurement from the bottom of the chine on one side to the bottom of the chine on the opposite side of the boat’s bottom. A wider bottom width is important because it contributes to stability, capacity and speed to plane. North River’s bottom widths in the Seahawk OS series are nearly as wide as the beam, providing for both stability and maximum usable space on deck.

Deadrise
In addition to bottom width, a boat’s deadrise is an important factor in wave cutting ability and ride comfort. Deadrise is measured in degrees. The more deadrise, the steeper the V. The combination of a wider bottom width and a deeper V gives you increased carrying capacity, increased stability, faster planing and a far more comfortable ride in sea conditions like those found in the Pacific Northwest or the Great Lakes.

Integrated Engine Bracket
A feature that Mike likes to see in aluminum boats is an integrated engine bracket that follows the contour of the hull, as opposed to being stepped up and sitting above the hull. The integrated offshore motor bracket is an extension of the hull providing you with more planning surface and improved outboard motor support.

Chine and Lifting Strakes
Another bottom feature to look for is an aggressive reverse or step chineto provide additional lift while planing and additional stability when at rest. Lifting strakes welded to the hull provide additional lift when planing and lateral stability when turning.

Boat Length
It’s important, when considering a boat’s length, to look at the centerline length. North River provides an advertised length measuring from the bow tip (excluding pulpit) to the transom (excluding offshore bracket). Other manufacturers advertised lengths may include the pulpit and/or motor bracket. When comparing vessel hull length, it is important to know what you are getting. For example, a North River Seahawk Offshore 2700SXL has a centerline length of 27’ with an overall length (excluding motors) of 30’ 3”.

Quality of Components Used
Mike points out that when evaluating the boat, it’s important to consider the quality of the components. Like in cars, the better the quality of the components, such as the fit and the finish, the better boat you’re getting. North River uses marine grade, premium quality components that can be sourced nationally from most any marina. Our boats are used everywhere, and it’s important to have commonality in components.