consult some specific word

[CHENZHEN]

who can help me explain these specialized Terms： ? Moment to trim 1? ?，?HOOK OR ROCKER?，I don't understand them。Thanks For Any Help !:redface:

 

[smokeonthewater]

Re: consult some specific word

can't figure out the little symbols in ur post,or the "moment to trim 1" thing but, hook or rocker refers too the shape of the bottom of the hull .. both being other than flat front to back, rocker curves down then up such that it would theoretically rock and would cause the bow to go up at speed and possibly porpoise, hook curves up and then down and will tend to force the bow down at speed.

 

[oops!]

Re: consult some specific word

yes........it referes to the shape of a planing hull

imagine hook to be a frown..........and rock to be a smile.

a hook can be dangerous......as it causes suction on the hull and will cause all kinds of handling / speed problems.

rock......can be good up to a point. if there is too much hook.....the boat's bow will pop up and down when at speed.....that is not good.

 

[DuckHunterJon]

Re: consult some specific word

Good answers on hook and rocker. I'm going to guess on the first one - is it a momentary switch (meaning, a switch you hold down to make the connection) that is used to adjust the trim? Again, just a guess.

 

[Ned L]

Re: consult some specific word

They are not necessarilly 'bad'. Either rocker or a hook can intentionally be built into a hull to improve performance.

 

[oops!]

Re: consult some specific word

i didnt see the trim question in there....

the trim is about changing the angle of attack of water passing the hull and onto the drive section of the boat.....

when you start to give the boat throttle.....the drive( propeller part) is in the full down position.....this will help move the boat forward, with the nose up just a bit.....and help get the boat over the water that is being pushed away by the hull......(bow wave) once the hull is on top of this wave....it is fridng on the water instead of pushing thru it, (or displacing the water)
when you trim a boat, you adjust the drive up a bit......this allows the motor to run at the same degree as the water line (angle of attack) in relation to the hull.

a "moment of trim" is when you adjust the drive.

by the way......as for hook and rock......some boats have a slight hook.......this causes the stern to rise a bit....and it can be good. however, the hook has to be correct or it will not work properly

 

[Texasmark]

Re: consult some specific word

They are not necessarilly 'bad'. Either rocker or a hook can intentionally be built into a hull to improve performance.

Well sir, I would like you to give us some examples of what that can do for us.

Thanks,

Mark

 

[smokeonthewater]

Re: consult some specific word

rocker can help a bow heavy boat get the bow up and run more efficiently and rocker can help keep a stern heavy boat from porpoising acting much the same as trim tabs