Myth busting – Does the Aluminium Boat Trailer Really stand up ?
For years Mackay has been building Aluminium boat trailers in Melbourne for a variety of different boats from Jet skis, up to 4.5T Power Cat applications. With strong engineering expertise Mackay has been able to design Aluminium trailers to suit a variety of boat requirements (as per pics below).
Many boaties are however still a little apprehensive about the use of Aluminium in boat trailers. This brief Q&A summary helps to dispel some of the myths of Aluminium and get the facts straight.
What are the real benefits of Aluminium over Steel ?
Major benefits include the weight saving potential (at least 25% lighter than Steel), being easier to maintain as will not rust like Steel, and eye catching aesthetics. A Mackay Aluminium trailer provides for:
Is Aluminium more likely to crack compared to Steel ?
Failure of any structure is a function of the design. If the trailer, be it in Aluminium or Steel, has been inadequately designed, poorly manufactured or improperly used, than the trailer or some parts of it will fail. Like Steel, Aluminium comes in a range of alloys (or compositions) each with its own characteristics in terms of strength, formability, toughness etc. Mackay uses mainly structural 6082 Alloy Aluminium providing the highest level of rigidity and strength.
Is Steel ‘stronger’ than Aluminium ?.
Aluminium is structurally more ‘efficient’ than Steel, meaning it can carry the same load as Steel with less weight itself. Aluminium beams however need to be sized up by approx 50% or more compared to Steel, to provide the same load capacity, thus Aluminium trailers typically have larger size profiles than Steel trailers. Steel has a higher yield capacity than Aluminium and will not fracture as quickly as Aluminium – again subject to the design of the item. The bottom line is that while Aluminium behaves differently to Steel it can certainly provide the strength required for boat trailer construction, and more.
What is better – bolting a trailer frame together or having it welded ?
Both joining approaches can be used if properly designed and applied, and there are advantages and disadvantages to each. Welding is more widely used in industry, including boat building, & construction. Welding allows for the stresses to be spread across a wider area, and for joins to be rigid. Bolting is an easier joining process, but creates more stress around the joins and consideration needs to be given to the different materials being used and the effect of aggressive electrolysis between them, say Aluminium and Stainless Steel bolts. There is also the issue of fastener maintenance and ensuring that the many bolts do not loosen, particularly if the trailer is going to be used over long distances and off-road. Many of the bolt-together Aluminium trailers are imported in kit form from China or the U.S., and have simply not been designed for Australian conditions.
How can electrolysis be prevented ?
Electrolytic corrosion (electrolysis) occurs on trailers when two dissimilar metals come into contact with each other through immersion in an electrolyte, i.e. salt water. Electrolysis cannot be prevented completely, only minimized. Ensuring that one’s trailer is washed down after use, and stored dry in a well ventilated space is a minimum requirement. Use of a sacrificial anode, or an alternative active circuit with a cathode and anode will also help – particularly if the trailer is stored outside in the weather.
Why buy a Mackay Aluminium Boat Trailer ?
Mackay has been building boat trailers for over 40 years, and specifically Aluminium boat trailers for 4 years. With strong in-house engineering expertise, Mackay have combined the best of boat trailer building experience with engineering know-how to develop a bullet proof Aluminium boat trailer. The trailers are designed for maximum rigidity, which minimizes the sorts of stresses and strains that contribute to frame fatigue. Material selection is crucial, as is our Aluminium welding expertise and experience. Mackay is able to provide the benefits of an Engineered Aluminum boat trailer that is reliable, performs well and goes the distance !