Thread: Offroad Boat Trailer

This rig is a few years old now but I am posting these pics and details as a few queries have come up about it.

First my opinionated rules for true offroad boat trailers - gained from few years of glueing busted trailers back together!
By true offroad I mean take it up the OTL to the west coast or drag it through 80km of mud in the wet.

So an offroad boat trailer MUST:
1/ track the same as the tow vehicle.
2/ run full size hubs/stubs and bearings.
3/ have excellent support for the keel and hull.
4/ have the boat firmly attached to the trailer such that they move as one entity - no loose fitting straps... use turnbuckles and locktight.
5/ The outboard (more importantly the transom) needs to be supported in as low trim a position as possible.

All of this generally keeps them under 4.5m and 60hp.

This rig is for a Hornet 435 (180kg) and yammie F60 4st on the tiller (120kg)
the usual suspects such as foot control leccie and batteries travel in the rig as well as miscellaneous camping gear... total GCM is 749kg

-Trailer was built for a mate who has cruiser and hilux as vehicles so it runs on tojo 6 studs, 75 series front axle hubs and stubs.

-Trailer tilts to enable easy loading/unloading on shallow ramps (read off the flat sand)
-Keel support is a row of 50mm Delrin rollers on 150mm centres.
-Chine support is 4x2 hardwood planed to shape
-Motor is transported at about 15 degree trim angle with timber support under the ram and strapped securely to trailer.

Photos suck for detail... but Ill try to point out details.

First images are of the triangulated 4 link suspension:
-It uses landy front coil springs riding in a hacked off ranga front spring bucket. Limit straps inside the coils and bump stops. Ride height is 300mm of spring runs 100mm of droop (controlled by straps) and 100mm of compression (controlled by bumps).
-Axle is stepped and laminated to enable vertical separation of links.
-Uppers are horizontal triangulated. Lowers are parallel to travel and angled downwards (slider strong). Links use standard tojo poly spring bushes apart from upper links to axle joint that uses adjustable Heims.
-Dampers are standard tojo patrol dimensions eye-to-eye configuration.

Steve

Sorry no pics, can get some though?

At the front winch there is a turnbuckle pulling nose down and backwards to frame
At the rear a pair of turnbuckles run from lugs on trailer frame up to the gunnels of the Hornet.
And then a ratchet strap (75mm wide) runs across the gunnels just in front of the guards.

Another good option if you can work it (too many grab handles on Hornet to make it work) is a length of 4x2 hardwood on edge across the gunnels with lengths of threaded rod down to frame lugs. The threaded rod goes through the 4" section of hardwood down each side of the hull, big washer and a couple of nuts with locktight.

S