Dolly Slings

B

biju

New Member
New to the sport and have just purchased a Laser but am away from a Club Environment to see and ask things. I'm and in Central America where buying and shipping things triples their price, so I'm about to build a Dolly so I can wheel the boat to and from our beach house into shallow water on my own. The Dolly will be used to store the boat in down time out of water and to allow launch and retrieval on my own.

So couple of questions. I am going to build the dolly based on the Seitech design but don't understand the principle of the sling and the flip up brackets. Should the boat be stored on the sling or on the brackets supported by the Gunnels and if so what is the point in the sling or why are the brackets flip up.

The other point is should the wheels of the Dolly be over the centre of gravity/pivot of the boat or set slightly aft. I've looked for designs but they seem sketchy at best and don't have the luxury of looking at an example and measuring/copying it. Any other points in the design/idea I may have missed gladly accepted.
 
You want to store the boat with the brackets up as this puts the weight of the boat on the gunnel rather than the hull. The gunnel is a rigid structural point where as the hull may become deformed if left on the sling. The sling can also trap water against the hull, causing bubbling in the gel coat.

When it come time to launch, the brackets up are inconvenient. They tend to get caught in the lip of the gunnel. Flip them down, and use the strap. The strap allows the hull to easily slide off and on the dolly when launching/retrieving.

As far as positioning the wheels, I'd say put them slightly aft of the center of gravity. This will help keep the boat on the dolly as you are moving it around. You don't want the bow to pop up and the drag the stern across the boat ramp or parking lot.
 
Thanks. So the sling is just to aid easing the boat on or off by sliding it off the dolly. I guess you lift the boat at each side and flip the bracket down so the boat then sits on the sling and then slide it off the dolly. Not sure I follow why is the sling required and the brackets need to fold down. If the Dolly is wheeled slightly further into deeper water won't the boat float off?

I guess my angle is the sling and folding brackets are quite a lot of extra Engineering for a home made project, although I have the capability to do these mods if they are must haves over niceties - so I need to fully understand it first.
 
The Seitech dolly uses inflatable wheels, so it tends to float at the surface even in deeper water. With the brackets up, they just tend to get wedged into the lip of the gunnel and not let the boat slide off. The combination of the sling and floating wheels helps keep the boat oriented in the dolly at you are launching or retrieving. If there is any kind of wave action at all, you would not be able to keep the boat straight.
 
Great. My wheels are probably buoyant but are solid and not air filled and with the weight of the aluminium frame I doubt the Dolly will float. We have a Barrier reef so little wave action so with all this I'm thinking so I will build rigid gunnel supports. Thanks for the help.
 
You must log in or register to reply here.

Back
Top