Please teach me about TRIM TABS

[trueblue]

Ok, got a set of big trim tabs working on the boat now. Tabs are 460mm wide and 220mm long, each.

Boat is a 18 foot mono.

I've been told these tabs ''can be savage''

What do I need to know about using trim tabs, especially big ones?

When to use, what the effects are, what the dangers are, etc, etc

cheers

Mick

[ozscott]

Mate it is very boat dependant. BUT big rule of thumb is use them in very short bursts otherwise you can dial in too much. For taking off I trim mine fully up and the motor in a little and gun it then out with the motor a little and then trim the boat with the tabs and then trim the motor with the trim switch...you get used to doing it all pretty quickly and slickly...and from that point on I tend to use the tabs mostly and leave the motor properly trimmed as is, but I play with it too

For sideways trim just use them in very short bursts on one side.

Cheers

PS. Really mate experimenting is the go, but just be aware that those size tabs if you stab one side down too far she might well list very badly which isnt a good day out

[Chimo]

As above, just make very small tab moves by tapping the control. In my case with Lencos 2 secs on the button is full travel.

I suggest you go somewhere quiet and have a play. Before you launch the boat get somone to press the contol and count one thousand one one thousant two etc and get to know how fasrt they move.

Then when in the water leave them up and do a water ski type start then repaeat with the tabs down and not the difference in time to plane.

Next have a slow cruise at just above planing and adjust both by tapping and watch the bow of the boat drop

Next at the same speed do one at a time and note the effect on boat trim side to side

If you want proof that you make small adjustments put one fully down and have the other up and have another ski start but be prepared to stop quickly as you wont enjoy the sensation. NB Leave the wife at home for this one or you may put her off.

Generally tabs are an acquired taste with experience gained slowly by doing. I too tend to leave my motors trimmed out more when i take off and thats due to the tabs even with them up.

As Ozscott said make little moves with the controls.

Cheers
Chimo

[trueblue]

I've already timed the controls.

6 seconds to fully extended, and 8 seconds to fully retracted.

and fully extended looks like aeroplane flaps run all the way down.

I can see that she will be a bit scary as I was advised if over done

cheers

Mick

[trueblue]

I am also hoping that these trim tabs will allow me to trim the motor out fully but keep the bow down and be able to troll more efficiently

[FNQCairns]

Stuffing the bow into a wave because you can now flat plane better forceing lots of bow down to smooth the ride when it's hilly.

Also when in following swell keeping too much tab down can force a broach(sp) if you don't lay off the tabs as speed increases down wave.

Think you will luv them.

cheers fnq

[Getout]

Tabs made a world of difference to my boat. I have learned to give them short bursts (there is a delayed reaction, as others have pointed out). They haven't improved economy (more the opposite), but the ride is much better.
In all conditions, it is a case of balancing engine trim and trim tab to get the best ride. Too much trim tab down, causes the stern to lift and cause prop ventilation. Too much motor trim-in, causes broaching and wet ride.
On a long downhill run the other day, I found motor trim-out and a bit of down- trim on each tab, to be a good setting to maintain a higher speed. (in the bottom of the trough, the out-trim of the motor produced more lift.
I always lift the tabs before entering a bar.

[trueblue]

when are times that I should NOT use the trim tabs, ie, when is it dangerous to use them?

[krazyfisher]

if you are using the tabs to lower the bow than they are no different to the trim on your motor just work better, so when is it dangerous to trim your motor in.... following sea

[MyWay]

Mick

i use my all the time any weather any condition any place

1. always when u are on water tapp the switch only for 1/2 second to till you practice out (soon u will know how long u have to hold switch to level the boat)

2. when you driving your boat u are behind steering wheel looking at bow of boat
u got left switch and right switch
always look what is bow of boat doing and do not think on tabs at back (just forget about it . u may get just confused )


((i wane to say u probably already know as u where testing tabs on trailer :when u switch left switch the right trim is working and when you switch right switch left trim is working))

3. if is your left bow higher than right which mines your bot is lining on right side u

just tapp left switch to till your boat in level it my take only one flick for 1/2 second or few flicks to do this (you trim tabs are big and thay don't need much to level your boat

4. ones you level the boat than now if you wish to push nose of boat more down you you use boat switches (one at time or both at ones )

i hope this will help you

[trueblue]

with my tabs, the left switch is the left tab etc. not opposite switched.

Is that set up wrong?

[krazyfisher]

maybe not... depending how the switch is set up. as long as when you press bow down the tabs go down and port down on the button makes the starboard tabs go down etc... than it is all good

[tenzing]

maybe not... depending how the switch is set up. as long as when you press bow down the tabs go down and port down on the button makes the starboard tabs go down etc... than it is all good

My Bennetts are set up so that left switch operates left tab ."Down" on the left switch indicates left tab down (port) which in turn lifts the left side bow. This seems to be different to above but is how it is . just a case of learning it differently. All OK till you get on a different boat.
A few years ago I built a mountain bike from the frame up with a friend who owns a bike shop. He set up the brakes with the front on the left as the cable run was neater. I tried it ONCE. It is a thing you learn over a long time and the skin took a while to grow back.
I guess this exercise could be the same.
Brendan

[trueblue]

mine is like yours Brendan. I'll have to check out the 'standard' and then wire it to be like the norm

cheers

Mick

[krazyfisher]

now you got me thinking.
I will have to check mine