We have recently introduced a strong, lightweight aluminum trailer to replace our older steel trailers.
There are two models: (See the price list section of this web site (click here) for prices.)
The standard trailer has an aluminum frame, a painted torsion bar axle, fiberglass fenders and a bow stand with no boarding ladder.
The deluxe trailer is similar to the standard trailer, except that it has surge brakes, a galvanized torsion bar axle, aluminum brake caliper holders, zinc plated disc brake rotors, and a boarding ladder near the trailer hitch.
I suspect that most customers will opt for the deluxe trailer package, since most states require trailer brakes. The standard model will be useful as a yard dolly or as a shipping cradle, and we expect to sell a lot of these to the overseas markets and any area that does not require brakes on the trailers.
Surge brakes are simple and reliable. When the car brakes are applied, the boat trailer begins to push against the trailer hitch, and an actuator built into the trailer hitch creates pressure in the hydraulic system to generated force to activate the trailer's disc brakes.
The aluminum trailer is about 180 pounds lighter than the comparable steel trailer. This is a big benefit.
Both models of the aluminum offer superior corrosion resistance. The deluxe model, with the galvanized axle and zinc plated brake parts, will be about as corrosion resistant as a trailer can be. The aluminum is not painted, and should retain its good looks for a long, long time. Steel parts are being painted with epoxy primer and linear polyurethane (Dupont Imron).
BOW STAND AND AND BOARDING LADDER
On both models, the trailer tongue and bow stand will be painted steel. We are required by law to have a steel trailer tongue (tow bar). We are better off with a welded steel bow stand and boarding ladder to avoid drilling more bolt holes in the 3” square trailer tow bar. The bow stand is the least likely part of the trailer to get in the water, and the painted steel should hold up well. Everything else on the trailers is aluminum, stainless steel, plastic, galvanized steel or plated steel, wood and carpet. Not much to corrode here.
CORROSION PROOF FIBERGLASS FENDERS
The fenders are fiberglass, and are rather nifty looking. The license plate and tail light holders are corrosion proof plastic (the same material as the sliding hatch rails on the MacGregor 26).
The main frames rails are I beams, 3 ½” x 5” with .280" flanges. . These are a lot more massive than the steel C channel, and the trailer looks a lot more substantial.
TRAILER I BEAM SIDE RAILS
The vertical guide rails are aluminum, taller than on the steel trailer, and keep the boat centered.
We have eliminated the 2 guide tubes on the bow stand. As the boat comes onto the trailer, the steep V support at the front of the hull centers the boat nicely into the rubber bow block. This saves some weight and complexity.
TORSION BAR AXLE END AND SURGE BRAKE ASSEMBLY
This is a
photo of the torsion bar axle. The marine industry is switching away from springs
and shackles to the torsion bar system. Virtually all of the
aluminum trailers being built for the marine industry sit on torsion bar
axles. They are more costly, but well worth it.
The axle itself (3” x 3” x .180 wall) is bolted directly to the trailer frame. There is a rubber sleeve in each end of the axle. A smaller square tube fits inside the rubber sleeve, and the rubber allows the smaller tube to rotate to a limited degree within the axle tube.
The wheels are mounted to a trailing arm that is part of the smaller square insert tube. The up and down motion of the trailing arms, rotating against the rubber insert, provides the springing action.
The trailing arm fits over splines in the insert tube, and the angle of the trailing arm can be adjusted to raise or lower the trailer. These systems provide a superb ride and are very durable. This is high quality stuff made by one of the best axle suppliers in the industry.
To save weight, we have a length of 5/32 upper shroud wire steel cable across the trailer to catch the daggerboard if it comes undone. This replaces the 1” pipe used on the steel trailers.