Dario's Lab

A Class Catamaran Trailer

An economical, quick and practical conversion from an existing ‘generic’ flat frame trailer to a specialised A Cat transport…  Not the most glamorous part of a development campaign, but necessary.  Getting this right will make life easier day in and day out during long testing and practice campaigns.

Before:

And after:
The parallel side rails support the cross beams just inboard of the hulls.
At the rear they curve downward and can accept ‘extensions’ that plug in the back to act as ‘ramps’ so the boat can be slid on/off by one person.
Side splashes aft are retained to catch the bows as the boat transfers to the launching wheels.
For loading and unloading the aft mast post is removed by sliding it up off its lower telescopic element which is welded to the trailer frame.
Once the boat is loaded, the aft post prevents it sliding back whilst the mast splash holds the aft beam down.
Two clamps over the front beam at the side rails, and both mast posts, are secured with screws that have ‘T’ handles and tap into nuts welded on the adjustable elements.
The biggest challenge seemed to be finding a suitable storage box readily available and at a reasonable price.
Even fabricating a custom box requires considerable materials and much labour.
A lockable roof-top box off eBay provided a ready solution.
It can easily take two sails, the boards, rudders, booms, wires, assorted spares, and a tool box.
It is also streamlined (for what that is worth in fuel consumption savings given that it is in the wake of the towing vehicle), looks sleek and, in extremis, can be quickly commandeered for the occasional skiing trip…
Oh, and, being plastic, it does not rust.
Next to the box is a readily available length of plumbing pipe with screw cap ends to take tiller extension, cross bar, trailer rail extensions, and a can of emergency tire foam.
Towed the trailer 400Km to pick up the boat (next test platform – Yay!) and 400Km back with the boat.
It handled nicely and fuel consumption was noticeably lower than with the old heavier trailer with conventional square metal box.
Metal fabrication by Marcus and Rose MFG P/L, Carringbah NSW