[Rhodes22-list] Dynamic Equilibrium's Trailering Tiedown System (Was Trailer Follies)

[Roger Pihlaja]

Hi Everybody,

The subject of how & whether or not to tie-down the boat to the trailer has come up before on the list.  As far as the question of whether or not to tie the boat down; remember, Newton's Laws of Motion apply everywhere all of the time.  In a collision or sudden maneuver, your Rhodes 22 is an oddly shaped 3500+ lb mass moving at highway speed with all the inertia & momentum that fact implies.  Therefore, of course you should secure the boat to the trailer!  I would suspect if you didn't properly tie the boat down & the boat came loose causing injury &/or property damage; then, you would be declared negligent & held criminally liable.

The attached article & annotated pictures below illustrate how we tie-down Dynamic Equilibrium to its trailer.  Our trailer is a tandem axle Lil Dude; but, the principles should be applicable on any trailer.

Note, I used to use a single 3 inch wide HD strap over the gunnels, across the cockpit, just aft of the cabin.  In fact, I still have the strap and the HD padeyes on the trailer.  This single strap system is better than nothing and will probably keep you out of jail for negligence.  However, this single strap system will not prevent the boat from shifting from side-to-side in between the keel guides over bumps &/or during a sudden maneuver.  This side-to-side shifting of the boat on the trailer is bad for a couple of reasons.  First, it shifts the center of gravity of the boat/trailer system, thus making the boat & trailer more likely to roll over.  Second, the side-to-side shift causes the weight of the boat to be carried on a different part of the hull than designed and places a greater portion of the load on one side of the hull vs. the other.  All of this off-spec load shifting can't be any good for the hull, trailer structure, bunks & supporting structure, trailer wheel bearings, trailer tires, etc.  In addition, the geometry of the single strap system makes the strap susceptible to vibrating at highway speed due to aerodynamic forces, thus chafing the gunnels and topsides.  The two strap system illustrated below automatically keeps the boat centered between the keel guides during any reasonable maneuver or bumps.  It is also much less susceptible to wind-induced vibration & chafing because the straps are not sticking out in the wind stream like the single strap system. In addition, the only points of contact with the hull are on the corners of the transom, which are protected by bottom paint.  Note the use of soft plastic anti-chafe pads at critical points.     

Roger Pihlaja
S/V Dynamic Equilibrium

----- Original Message ----- 
From: Roger Pihlaja 
To: The Rhodes 22 mail list 
Sent: Friday, August 15, 2003 9:30 PM
Subject: Dynamic Equilibrium's Trailering Tiedown System


Hi Everybody,

A couple of days ago, somebody asked how to safely tiedown their R-22 to their trailer.  The two attached photos show how we do it on Dynamic Equilibrium.

Up on the bow, we use two extra tiedown straps.  One tiedown strap backs up the trailer's winch.  This tiedown strap gets attached to the bow eye as soon as the bow is winched up against the trailer's V-shaped bow stop while the boat is still in the water.  That way, the bow is held solidly against the V-shaped bow stop and there is no possibility of the trailer's winch coming unlatched & allowing the boat to slide backwards off the trailer while it is being pulled up the launch ramp.  The second tiedown strap prevents the bow from rising up or sliding forward under heavy braking.  This second tiedown strap is not attached until the boat & trailer are ready to hit the road.

At the stern, we also use two extra tiedown straps.  Note how these tiedown straps attach onto the transom lifting eyes and crisscross under the hull before attaching to a pair of stainless steel padeyes bolted to the trailer's frame.  This crisscross diagonal tiedown arrangement note only secures the stern from rising up or sliding backwards, it also prevents the hull from shifting side-to-side.  Note the use of four IMCO F13180 plastic anti-chafe pads at strategic points to protect the hull.  These two tiedown straps on the stern are normally the last things to be secured before the boat & trailer are ready to hit the road.

All of these pieces/parts are available from West Marine.  Note: You might need slightly different length tiedown straps &/or padeyes to fit your trailer because my trailer is a Lil Dude tandem axle model, not the OEM Triad model.  But, the basic strategy should work as well on the OEM Triad trailers as it does on mine.

It's a pretty quick & effective tiedown system.  We have a lot of launches/retrevals and thousands of trailering miles on ours.

Hopefully this answers your trailering tiedown question.  Enjoy!

Roger Pihlaja
S/V Dynamic Equilibrium
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