The Case For Welded Aluminum Boat Construction

   In comparison to fiberglass, a welded aluminum hull will yield a more durable and longer lived boat. Additionally when customized to customer requirements, it can easily be retrofitted should operating requirements change. It can also be easily and quickly repaired if need should arise.

General

   Aluminum is the first choice of government agencies for boats in the 20 to 65 foot range. Aluminum is used for most small to medium sized commercial fishing boats in the northwestern US, and it is used in most crew boats in the Gulf of Mexico. Aluminum has long been accepted as the premier material for fine yachts, both sail and power, and has been the choice for most America's Cup sailboats since 1974.

   Approximately half of all boats built in the U.S. are built of aluminum alloys. Small thin hulled boats, are fastened with rivets, with welding processes being used on thicker sections. Aluminum boats plated with 1/8 inch or thicker material, such as that proposed, are "fastened" using the metal inert gas (MIG) welding process. Aluminum has a higher strength to weight ratio than most other boat building materials. Aluminum has exceptional dent resistance and aluminum boats typically weigh 30% to 40% less than their fiberglass counterparts and 45% to 55% less than their steel counterparts. A reduction in weight provides a number of performance enhancements. For any given sized vessel, lighter weight can yield greater speed with the same horsepower, reduced fuel consumption, and or a greater payload capacity. Light weight vessels also provide reduced draft for a given payload.

Durability and Repairability

   Aluminum has excellent durability. It will withstand impacts that neither steel nor fiberglass can take. Like steel, aluminum has considerable ductility; i.e. the ability to withstand permanent deformation without rupture. It has one third the modulus elasticity of steel, thus it will have more absorption of energy in an impact, over a greater distance. Stress levels therefore are considerably less than would be the case in steel impact. Fiberglass, on the other hand, is extremely brittle and is thus subject to cracking and fracture during impact.

   Aluminum boats are much easier to repair than fiberglass boats, particularly fiberglass boats with foam liners. Dents can often be pounded out with a hammer, but if necessary, sections of a plate can be cut out with a saw and replaced.

Flammability

   Aluminum doesn't burn in a solid metal state. Fiberglass boats contain petroleum based resins which burn energetically. Fire retardant resin makes them harder to "light", but the burning is energetic once started.

Ease of Customization

   Since aluminum boats are not built from molds as fiberglass boats are. Therefore changes in design, modifications in the location of bulkheads, size of cabins, etc. are all accomplished more readily than with fiberglass. The ease with which equipment can be relocated by cutting and welding or drilling and bolting is also advantageous. With the advent of Computer Aided Design (CAD), custom hull shapes and arrangements can be provided at prices which are competitive with low volume production runs.

Corrosion Resistance

   The salt water corrosion resistance of 5000 series Aluminum is excellent. This has been demonstrated by the Aluminum Company of America (ALCOA) in a thirty year test from the mid 1930's to the mid 1960's. At that time a section of an aluminum hull was retired from its test site in Narragansett Bay because so little had happened to it. Problems with aluminum boats can be traced to either the use of improper alloys, galvanic or electrolytic corrosion. These problems are eliminated by proper zinc protection, material selection, proper wiring, bonding and isolation procedures.

Summary

   Because of the advantages of aluminum in the marine industry our boat manufacturing business has spawned fabrication work, not only for our own boats, but for other builders and boat owners as well. We offer custom design and fabrication services as well as production runs for larger quantities. Please contact us so that we may address your specific needs.

A word about workmanship:

   The same tradesmen design & build our fabrication work that build our C-Craft Boats; boats which have gained an excellent reputation for longevity and craftsmanship.