Setting The Rocker By "Hand and Eye"

[beekeeper]

Boats built from plans are built to a set amount of rocker. Setting the rocker to a specific setting useing the traditional, "cut an arc in the side panels", was hit and miss for me. Gator Boats attach the chines to the floor and then the sides. http://www.gatorboats.com/ My Croc model was built this way. The rocker is set by the design. I proposed the question, "Could the chines be attached to the floor, and then adjust it to the desired rocker? Attach the sides and then cut them flush." http://www.gatorboats.com/forum/viewtop ... highlight= This should allow the builder to get what ever rocker desired.

The answer is YES.

But not easily on the first try. :cry: Is it practicable? Yes, with practice and planning. I wanted 1.5" of rocker at the bow and 1" at the stern. It came out on the money.

Build the frame (chines and floor ribs):

Attach the floor to the frame:

Place over saw horses:

Adjust floor with weight and set the rocker to your measurements. I used a laser level:

I cut the top of the sides to the shape I wanted. This had to be redone after the sides were attached, because the height was wrong.

Attach the sides and cut flush:

It will be some time befor I can try the boat, but I am pleased with the way it turned out.

I am not saying this is a better way to build boats. It was not easy, because it was uncharted territory for me.

beekeeper

 

[seedtick]

now you can use your side cutouts as an "other side" pattern for cutting future sides that will give you the identical rocker.

 

[beekeeper]

now you can use your side cutouts as an "other side" pattern for cutting future sides that will give you the identical rocker.

I kept them, but wouldn't I have to build the identical boat for them to work?

I started this project with a 1/2 scale model, with the intentions of setting the rocker by marking the sides while they were attached to the forms. After making the model , I used those measurements to cut a full size side. I then attached the inside chines and proceeded to break the side (5.2mm luan) when I was bending it. :cry:
I did compare the arc of the broken side to the actual side cutouts and they were close. I don't believe it would have been as exact as the way I did it.
I don't know if the results will be worth all the effort in the real world. I would like to understand better how to adjust/set the rocker to a specific amount useing the "cut an arc in the side" method. There probably is a computer program that could design what ever amount of rocker we wanted.


beekeeper

 

[beekeeper]

WARNING/CAUTION

I have learned why I had trouble fitting the stems. The chine logs have to be planed to the matching angle of the sides as it decrease on each end. I held 30 degrees all the way. The Gator build method gets by this because their sides flare less for their designs. The picture shows how spread out the log held the sides. I don't think there is a practicle way to know how much to plane off, the way I built this one. Swampwood's build is similar, but his chine log is planed flused to his stations (form). Thanks seedtick and swampwood for the lesson.

I have to say if you want to build to a specific rocker use plans or a form.



beekeeper

 

[tx river rat]

It Is sure fun to play isnt it.
Ron