Steel and Aluminum

Steel is an excellent boatbuilding material, proven in use worldwide. However, due to the relatively high weight compared to other boatbuilding materials, and the care required in the design stage with regard to hull development, structural integrity, stability, and balance, the plans used to build a steel boat should be intended specifically for use with this material. Using plans for a design intended for some other material and converting it to steel should not be done, at least without careful (and usually costly!) redesign by a qualified naval architect. That's why GLEN-L has developed a series of low cost stock designs intended for steel construction.

For the amateur boatbuilder who has knowledge of proper weld types and welding sequences, together with the necessary electric and gas welding skills, steel is an ideal material. On a cost-per-square-foot basis, steel is probably the cheapest of all boatbuilding materials. Construction is simple when using the building methods specified in GLEN-L plans, and faster than just about any other boatbuilding material. No special shelters or structures are required, and the materials are readily available just about anywhere without special order. For strength, steel is just about tops in all respects. Repairs and modifications can be easily made anywhere in the world as long as a welding set is available.

Even if you don't know how to weld, acquiring the necessary welding skills is relatively quick and easy. Numerous welding schools and classes are available in most areas, either through public school systems or through private trade schools. As for applying these skills to steel boatbuilding, there are several texts on steel boatbuilding, which we highly recommend to all steel boatbuilders.

To further put steel boatbuilding within the realm of the amateur, ALL GLEN-L steel boat plans include our comprehensive "STEEL BOAT-BUILDING MANUAL" to supplement the plans and abilities of the builder. This general instruction manual discusses the various building procedures and options for setting up, proper hull assembly sequence, welding recommendations, tank construction, insulating methods and materials, joinerywork, electrical, finishing, and much more. To enable the builder to fabricate many of the usual "store bought" parts, the plans are further supplemented by numerous detail sheets showing hatch construction, rail details, rudder fittings, shaft tube and stern bearings, mast steps, chainplates, deck details, cabin-hull junctions, and joinery details.

Full size patterns mean even faster construction since no lofting is necessary. For those who desire to loft their boats, however, a Table of Offsets is also provided. And of course, our comprehensive plans include all the typical information you'd expect to find in a GLEN-L plans set. They cover all aspects of the design including structural views and sections, scantlings, cabin construction, joinery arrangements, tank configurations, engine placements, rudders and underwater fittings, and spars on sailboat designs. In short, you get everything you need in the way of information to build your very own steel boat, and at a low price! That's why at GLEN-L we mean it when we say, "You get custom design quality at low stock plan prices."

The steel used is normally mild (plain low carbon) steel of welding quality, although corrosion-resistant grades, such as "Cor-Ten" (a trade name) are optional but more expensive and hard to work. Steel is usually sold in quantity by weight. That's why for each steel design we provide an estimate of the weight of the steel hull components. Simply use this figure times the cost of steel per pound in your area to arrive at a reasonable estimate for hull material costs.

Aluminum is also a superb material for boatbuilding by the person qualified in aluminum welding. Aluminum boats using welded marine alloy construction are strong, lightweight, durable, and easy to maintain. As with steel, the designs should be specifically intended for this material.

Plans listed for aluminum construction include all the details necessary to build the boat in sheet aluminum. As with all our designs, they include FULL-SIZE PATTERNS so that no lofting is required. In addition, all aluminum designs include our comprehensive "ALUMINUM BOATBUILDING GUIDE" as well as a hull material listing. See our "Boatbuilding & Marine Supplies" catalog for additional publications on aluminum construction.

The following can be used as a general guideline for selecting materials. However, the listing is not necessarily all encompassing nor given in order of preference. To figure hull cost, use weight of hull times cost per pound.

Hull plating and decking	
	5052-H32 to H36
	5086-H32, H34, H112 or H116
	5052-H32 to H36
	5086-H32, H34, H112, or H116
	5050-H34 or H36
	5456-H116, 6061-T6
	6061-T4 or T6, 5086
	5052, 6061-T6
	6063-T6, 5456-H116

When buying aluminum sheet or plate goods, the terminology "sheet" refers to material of .188" or less (nominally 3/16" or thinner), while the terminology "plate" refers to material .25" (1/4") or more.

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