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copie
20-07-2010, 09:12 PM
Why do trim tabs improve the ride on most boats when heading into a sea.
Mark

ozscott
20-07-2010, 09:18 PM
Marc - several reasons. Most boats have a finer entry that the v at the stern to allow slicing through chop. It also lengthens the water line length of boat in the water so it bridges more of the chop waves than just having a much smaller section in the water.

Cheers

wrxhoon
20-07-2010, 10:03 PM
The main reason is because the boat is always level if you use them correct. When the boat lands she lands very soft because she lands on the point of the V .

Scotts points are valid as well.

scuttlebutt
20-07-2010, 10:09 PM
Tabs can force the nose down so it doesn't bounce around as much, thus smoothing the ride. Also as Ozscott says, getting the bow to cut the waves more cleanly.

NTMID8
20-07-2010, 10:11 PM
Do they make a boat more stable at rest?

finding_time
20-07-2010, 10:23 PM
Do they make a boat more stable at rest?

Not that would be noticeable. there just not that big!

trueblue
20-07-2010, 11:30 PM
:o --------- mine are huge!

2 x 450wide mm tabs x 350 long on a 5.3 boat!

scary in fact

Flex
21-07-2010, 04:58 AM
Also if your headed into a sea at a slight angle, some deep-V boats lean into the wind, So that side of the boat is lower which allows more spray to come in I've found. With trim tabs you can straighten the boat up for a much drier ride

I honestly dont know how anyone can live without trim tabs on their big mono's.

When Im headed into a chop, I drop the tabs and can go fast as I like. without I'd be bouncing pretty hard

ozscott
21-07-2010, 07:46 AM
The main reason is because the boat is always level if you use them correct. When the boat lands she lands very soft because she lands on the point of the V .

Scotts points are valid as well.


That thought came to me after my post and when I had gone to bed...I guess the levelling of the boat from port to starboard is so automatic I had forgotten about it. If you are level anyway and there is no wind shear then the V sits level, so its about getting the nose down where it is finer and extending the waterline length to bridge more waves. If of course she is sitting at an lean left to right then the V cannot work properly cause she is smacking down more on the flat side of the hull which does not cut through the water. I had that problem in the bay with the Vag in higher wind and chop before tabs and the tabs are excellent.

To highlight the difference that tabs made into chop, even when there is no wind sheer just bring the front down with tabs, and then let it go right up again and see the difference - that ability alone is worth the tabs, but that and the windshear issue make them mandatory in my view on any monos over about 5m especially cabin boats.

Cheers

Chimo
21-07-2010, 07:59 AM
All the points regarding increasing the boat length and thus improving ride even at very low speeds (as well as high speed) apply particularly to the tabs that use a plate such as bennetts and lencos for eg.

The point about them being mandatory on monos above 5 m is so true.

Apart from the fact that you would be better off in a longer boat, there is probably a case IMHO, to be made for installing them on even shorter boats if the boat has lots of weight on the stern eg 4 stroke motors

Cheers
Chimo

ozscott
21-07-2010, 08:24 AM
Yep - good point Chimo

Cheers

Lancair
21-07-2010, 12:22 PM
Im putting a set of Bennett Sport Tabs M80 on my new boat. $901 delivered inc the Electronic position indicator and auto tab retract function.

Lancair

copie
21-07-2010, 08:19 PM
So whats the difference if i trim the nose down using the existing trim on my engine, why spend money on tabs.?????
Mark

krazyfisher
21-07-2010, 08:23 PM
additional trim and you can adjust the lean your motor trim is only in the center where tabs are on both sides and can be adjust with 1 or both

indy
21-07-2010, 08:30 PM
They are the best thing since sliced bread and once you have them you will wonder how you did with out them all those years.

blueline
21-07-2010, 08:31 PM
hang on guys, this is more of a qustion then an answer, but i use my trim tabs to level my boat side to side, but trim my motor to put the nose down into the big sea's, am i doing something wrong. on the way out if a bit choppy i will use both as my fule tank is back a bitand more wait at the back when fully loaded.

Greg P
21-07-2010, 08:48 PM
Use the tabs to trim your boats running attitude for sea/wind conditions. Trim the motor to run at it's most efficient position - you can pick up the sweet spot via the increase in rpm as you trim out the engine.

Jarrah Jack
22-07-2010, 01:23 PM
I was going to ask this seperately but its worth mentioning here I guess.

I've seen mention of some tabs the same as trim tabs but without the adjustable function. I think they are set on a spring/dampener or something. Anybody come across them? They sounded like the poor mans trim tabs to me but apparently the yanks use em.

stue2
22-07-2010, 03:51 PM
All the points regarding increasing the boat length and thus improving ride even at very low speeds (as well as high speed) apply particularly to the tabs that use a plate such as bennetts and lencos for eg.

The point about them being mandatory on monos above 5 m is so true.

Apart from the fact that you would be better off in a longer boat, there is probably a case IMHO, to be made for installing them on even shorter boats if the boat has lots of weight on the stern eg 4 stroke motors

Cheers
Chimo
Chimo, I prsume thats still your current boat with the twins. Do you run trims on it and are they worth it on the twin rigs as ive read else where that you dont need them on twins?

Also some boats like the trophy i think it is have molded trim tab inserts as standard in the hull.

cheers, Stu

Chimo
22-07-2010, 05:07 PM
Hi Stu

Yes it is my current boat.
Yes I run a set of Lencos on it.
I also have a set of foils on each motor.
The foils were fitted first and were beneficial in lifting the stern and aiding the transition to planing and also allowing a slower plane speed.
Some months later the basic Lencos were then added, by Seafarer, and even when not engaged they also add lift as they have effectively lengthened the hull. Obviously when tapped into action they ensure the hull is kept level which gives a smoother ride without the shoulder smack which occurs with deep vees when they run unlevel and the vee does not cut the waves.

I asked Lindsay Fry, previous owner of Seafarer, why trim tabs are not fitted to all the deep vee Seafarers and he said it was an issue of cost that buyers decided against even though he knew that the boats were better with them.

IMHO spend the money and you wont be sorry.

Cheers
Chimo

stue2
22-07-2010, 05:34 PM
Thanks Chimo. I have now got myself a vag with twin 90 etecs but she sits in the shed:'( .
If trim tabs can make even a twin rig run better then they will be fitted. I imagine that the tabs will trim more effectively and easier than the motors can.

Cheers, Stu

Wayne_Red
22-07-2010, 07:34 PM
They are the best thing since sliced bread and once you have them you will wonder how you did with out them all those years.
So true, the brother fitted QLs to his 6m victory, truely amazing. Put one fully down on flat water and you almost fall over the side with the boat at @30degrees (even with 3/4 people on the high side).
To answer the original question, as other have said,
1. keeps the boat square to the water in all conditions allowing the V to work as is was designed
2. trim the nose efficiently to allow the pointy end to cut into chop the way it was designed
3. Lift the stern and get the boat level and perform as it was designed to counter the weight of people/fuel/heavy outboards, especially 4s
Wayne

Angla
22-07-2010, 09:43 PM
I was going to ask this seperately but its worth mentioning here I guess.

I've seen mention of some tabs the same as trim tabs but without the adjustable function. I think they are set on a spring/dampener or something. Anybody come across them? They sounded like the poor mans trim tabs to me but apparently the yanks use em.

They are called Smart Tabs from www.nauticusinc.com

I have a set of the SX on a CruiseCraft 575 Outsider. For the 100 I paid I think they are giving me a better ride. Still playing around with the settings to see different outcomes on sea going ride when heading back in on a following sea and also fuel efficiency and cavitation as I had to take off my SE sport fin from the motor.

Cheers
Chris

Snapperscott
22-10-2010, 06:56 PM
I appreciate some help here.

I've just started using my trim tabs on my 2301 striper and yes it absolutely puts the nose down.. What a difference the boat just bumps along rather than crashing into the holes.

Question is at times they are bloody terrifying because I rarely get to go head on into the sea as im always running west to east with either a southerly or northerly sea. At times the boat will just start steering left or right rather quickly and I have to turn the wheel pretty quickly to adjust or slow down.

Does anyone else using trim tabs get this type of very uneasy feeling when using them.

Im mostly in 1m confused sea up here in Cairns.

I can really feel the benefit of them but it just feels a bit scary at the moment.

Any help would be appreciated.


Scott.

Flex
23-10-2010, 06:31 AM
Hi Snapper,

I have a 2101 striper with tabs, Which make the ride fantastic

When you say you have to turn sharply, Im assuming your travelling in some kind of following sea? or a sea coming onto one of your fear quarters? which causes the sharp nose dig in a bit?
You will need to fully disengage your tabs most likely or partially engage just one to flatten the ride and trim your motor our correctly. I find with my boat I cant just leave the motor trim and forget about it.

And Alot of people forget they have Motor trim when they get tabs.

I notice my striper is a bit sensitive to motor trim,But most deep V glass boats will be.
if Im in any sort of following sea I trim out and I can fly along no worries. Good indication if your steering starts to get heavy if you have incorrect trim in a following sea

Snapperscott
23-10-2010, 08:10 AM
Hi,

Definately not a following sea more of a right to left sea coming through the front right quarter that im trying to go through. What happens is the boat just starts to head right as if you were in a plane making a turn. I need to over correct it to get it back straight. The problem is it just feels really uneasy for me and for passengers.

I should say trimming my motor does very little for bringing the nose down. Very little at all. But I'm about to put on a stainless prop and lift the motor up a notch.


Anyone else have a sense of lack of control using the tabs?


Scott.

death_ship
23-10-2010, 09:34 AM
na mine produce quite the opposite effect! i have the lencos on a haines 580 breeze.

Chimo
23-10-2010, 11:55 AM
Hi Snapperscott

Anyone else have a sense of lack of control using the tabs?


Certainly not with my lencos, I find them consistant and useful.

Have you hav a fiddle with the tabs?

ie try one full up and one full down and then accelelerate from stationary. Keep your hand on the throttle so you can back off quickly when you see their affect.

put them both fully down then accelerate from stationary, watch the bow lift as you ease the tabs up

trim you motor out to the sweet spot (after you have the height right) and then fiddle with the tabs but just tap them to adjust preferably both together after your initial individual tapping on one to get the boat level

Tabs are great things after you get your head around just how little adjustment you need on well installed units.

Did I mention I luv mine!;D and the foils on both motors :D too

Cheers
Chimo

scuttlebutt
23-10-2010, 01:24 PM
Hi,

Definately not a following sea more of a right to left sea coming through the front right quarter that im trying to go through. What happens is the boat just starts to head right as if you were in a plane making a turn. I need to over correct it to get it back straight. The problem is it just feels really uneasy for me and for passengers.

I should say trimming my motor does very little for bringing the nose down. Very little at all. But I'm about to put on a stainless prop and lift the motor up a notch.


Anyone else have a sense of lack of control using the tabs?


Scott.

I get that Scott, happens when I put the tabs down too far. When using them to put the nose down you can only push them so far before it gets a bit doughy.

steve

DAZMC1
23-10-2010, 04:09 PM
Iv,e got a set of Bennett sport tabs on my Edencraft 565 and it juest goes straight ahead , no bad habits at all. When I go with a following sea I lift them just about all the way up , you can feel where they should be at with a bit of practise, thats why I just leave them as manual. I usually trim the tabs down and trim the motor up, but I,m always making small changes on the go.

Flex
23-10-2010, 06:42 PM
I get that Scott, happens when I put the tabs down too far. When using them to put the nose down you can only push them so far before it gets a bit doughy.

steve

Yeah sounds like you have em down to far if its into a head/beamish sea.
To far down you end up with to much steer in your bow,
as soon as a wave hits and pushes your hull a fraction off-course your boat then wants to keep steering in that direction

Getout
24-10-2010, 07:25 AM
I'm still amaazed by the Trim Tab conuundrum! They should be standard on all deep V hulls. Every second mono hull I see, travels along, with a list to one side. This can be caused by prop torque,wind effect,load position. A set of tabs will correct this and make the ride smoother because a level hull lands more softly. Sometimes, I wish I only installed the one on the port side, because of the prop-torque effect, I mostly use the port side tab and rarely use the stbd side one.
Yes they can help to lower the nose when punching into a headsea, but engine trim has almost the same effect.
Do they improve economy? I reckon not. The extra drag is noticeable, but the improved ride is worth it.
One thing that nobody ever mentions is that using tabs actually lifts the transom at speed and changes the height of the prop in the water, therefore requiring more down trim on the engine, to avoid ventilation.
I constantly adjust my tabs when running along, as people move about in the boat, as the wind changes, as the sea state changes, to get the best ride.
Oh yeah..in a following sea, its best to use little or no tab at all. The last thing you want is something forcing the nose down when you hit the trough of a wave!

odes20
24-10-2010, 11:32 PM
Hi,

Definately not a following sea more of a right to left sea coming through the front right quarter that im trying to go through. What happens is the boat just starts to head right as if you were in a plane making a turn. I need to over correct it to get it back straight. The problem is it just feels really uneasy for me and for passengers.

I should say trimming my motor does very little for bringing the nose down. Very little at all. But I'm about to put on a stainless prop and lift the motor up a notch.


Anyone else have a sense of lack of control using the tabs?


Scott.
This is a really helpful thread!

IMO the problem you are describing is from having your nose trimmed too hard into the sea which allows it to grab and grip and run off on a tangent. To me the advice to get your nose up would help you greatly and then just use your tabs to stay level from that point.
Cheers
John

fishfeeder
26-10-2010, 02:05 PM
Has anyone put QL's on a Vagabond ??
I am really interested in how they went and how they did the installation.

What sort and size do others think would work the best

Fishfeeder

Chimo
26-10-2010, 02:22 PM
Hi Fishfeeder

I have a Vagabond and have fitted tabs as an after market item.

I asked Lindsay Fry (Previous owner etc of Seafarer) for his recommendation and he advised Lencos that I subsequently had him fit.

Benefits are lengthened hull with more bum lift even when the Lencos are fully up and no extra drag (speed reduction and extra fuel used) which will be an issue more than likely with what your thinking of.

Great hull levelling so no more shoulder banging into head or angled off head seas.

Need to drill a hole thru the rear steps / boarding platforms to fit the screw drive and only a small hole up high for the electrical cable ( No hydraulics )

Used the simple toggle switches so no leds etc or self lifting gear to have issues with. You only need to tap for a split second to get the desired outcome with the Lencos. If you cannot feel where the tabs are maybe ..........?( I'm going be nice)


Have fun with the project.

Cheers
Chimo

fishfeeder
26-10-2010, 03:35 PM
I have a single Evinrude 200hp on the ass so maybe a bit lighter then yours. I was more interested in the leveling the ride and a bit slower planing for covering more ground when searching for fishies, seeing that the QL's disturb the water under the boat I was wondering if that will effect the transducer/readings (I have through hull).

Also the least amount of holes through the hull under the water can only be a good thing.

It seems there are a lot of good points for each unit so $$$$ might be the biggest factor

Fishfeeder

Chimo
26-10-2010, 04:00 PM
Too true as there is 135 odd kg difference.

The plate type tabs will give slower planning with little drag and next to no disturbance. i found this to be the case on another boat I had too.


Cheers
Chimo

death_ship
26-10-2010, 08:27 PM
new lencos come standard with auto retract, landed mine from the states for $750. (12x12 edgemount with standard switch)
check the measurement on the edgemount lencos as the ram is on a bigger angle so they dont come up as far and they may fit under the boarding step without needing a hole cut through. i just squeezed it in under the platform on my haines.

stue2
27-10-2010, 06:06 AM
Had a chat with hayden Whyld and they are cutting the mount off the tab and shifting it back then mounting the ram under the step on a vagabond. they use the short ram from bennetts.

cheers, Stu

sporty1
27-10-2010, 08:07 PM
Hi Guys

installing Lenco's this weekend (not very technically minded) it says in directions the orange wire is attached to Tacho to enable auto retraction. How is this done attached to what part or what wire of the tacho ? any help appreciated.

odes20
27-10-2010, 08:55 PM
Hi Chimo and Deathship and others, what would be the optimum size in a Lencos set of tabs to fit to my Yalta Odessa 2000 6.1 m (20ft) ??

Thanks everyone for an fantastic thread, I can't believe that in all the boating I do that i have not realized sooner how much these babies will assist my ride etc. My rig has a fair sized canopy so she always leans into the wind in a 12 knot upward sea, and i have now understood how much side slap I have been putting up with
Cheers
John

death_ship
28-10-2010, 05:35 AM
Hi Guys

installing Lenco's this weekend (not very technically minded) it says in directions the orange wire is attached to Tacho to enable auto retraction. How is this done attached to what part or what wire of the tacho ? any help appreciated.
can be any wire that loses power to it when the key is turned off. so when motor stops tabs come up. this wire sends the signal to the control box. if u dont hook it up they will still work but not auto retract.

death_ship
28-10-2010, 05:39 AM
Hi Chimo and Deathship and others, what would be the optimum size in a Lencos set of tabs to fit to my Yalta Odessa 2000 6.1 m (20ft) ??

Thanks everyone for an fantastic thread, I can't believe that in all the boating I do that i have not realized sooner how much these babies will assist my ride etc. My rig has a fair sized canopy so she always leans into the wind in a 12 knot upward sea, and i have now understood how much side slap I have been putting up with
Cheers
John
probably 9x12 or 12x12 edgemount
check it here
http://www.lencomarine.com/trim_tab_pgs/trimtabsizechart.html

Chimo
28-10-2010, 06:34 AM
Hi John

I forget what mine are but I'll go and measure mine later and get back to you.
On a Vag so probably similar to what you may need.

Cheers
Chimo

PS Forgot I had these pics with built in measurements

ozscott
28-10-2010, 07:00 AM
Yep once you've been flat you'll never go back. Mine are Bennett 120 sport tabs and have no trouble at all trimming my Vag even with it's big canopy and it's podless deep v. The hull is very responsive to them and they make it a joy to drive. Cheers. Ps eas to fit myself too. I did short rams for the swim platform. Excellent quality gear.

ozscott
28-10-2010, 07:04 AM
http://www.bennetttrimtabs.com/catalog.php?vID=78

stue2
28-10-2010, 08:39 AM
Mine will be M80 or 8x10 bennetts with the short ram so you dont have to cut holes in the steps on the back of the vagabond.

took the good ship for a run on the weekend and loved it. I thought it was a bit high in the front untill I looked at how fast I was going and realised it was taking a bit longer to land.
As with all brand new second hand stuff there was a couple of problems.

1, oil is leaking out of the seastar steering at a fitting.

2, both tacos went down?

3,A bloody great B double went past at a great speed and turned the canopy inside out, reparable but s#*t

cheers, Stu

Micadogs
28-10-2010, 09:47 AM
Hi Guys, Just fitted the 9 x 9 inch Lenco's to my 5.5 Fibreglass boat and tested for the first time. What a difference, even in calm water. I was able to test speed loss cause it was such a great day. At 41klms / hour I deployed the tabs, (over what was required) and only lost 0.5 klms / hour. This is a very acceptable loss of speed for a complete change in ride. Also, my slow planning speed used to be 18 kmph, it is now 13 kmph. What a signifcant change also. I also tested out "correcting the list" went onto a quarter wind and then had passangers stand to the listing side. Only took to position II to correct the list fully. Only lost 1/2 kmph again. Haven't tried them offshore yet - Saturday is looking real good!! regards Adam

PADDLES
28-10-2010, 10:04 AM
good stuff stu, i've only had trim tabs for about a year, but they are pretty handy things and i'd probably never own a big mono without them again. we've got bennet ones and like others have said, i don't use them to trim for and aft because i use the leg trim for that but use them more to keep the boat sitting upright when on the plane. if your boat is leaning over from the wind or weight distribution, the side of the vee that's leaning in hits the water very flat so having your boat sitting straight into a sea gets rid of this slap and the difference in ride is chalk and cheese. you won't look back mate. they do affect fuel economy though if you leave them down, but if you only use them to trim side to side the losses are minimal.

fishfeeder
28-10-2010, 11:24 AM
Stue2,

Did the top mounting bolts end up above the floor hight when installed under the steps ??

I was looking at the Lenco's Edge mount ("9 x 12") but I think either of them will work fine and I just need to work out what I am going to need to do and get before I spend the $$$$

stue2
28-10-2010, 12:25 PM
Sorry for confusion, I have twins and can trim farely well anyway, but my research has lead me to this conclusion and I have searched every where, hay chimo

8x10 M80 on the short ram, under the step, above the floor, but the mount on the tab is cut off and shifted right to the back of the tab. the hydrolics go up behind the back seat.

PS. reread my posts and call Wyld marine. they are the soarce of my info.

cheers, Stu

and good luck, PM if you want

Chimo
28-10-2010, 01:03 PM
Stu

Yours 8 x 10 = 80 mine 9 x 9 = 81 so sounds about right

Dont over fill the seastar as the oil expands when hot eg sun

Hope the sheep have got over their 'visitors'

Cheers
Chimo

fishfeeder
28-10-2010, 02:37 PM
Stu

Yeah I understand your posts.
Just needed to know really if the Top mount on the ram would be above the floor on the inside of the boat, So no inspection hole would need to be cut into the floor for the hydrolic lines... hope that makes more sense

stue2
28-10-2010, 02:41 PM
Chimo, good to hear.

One of the inlets has let go on the seastar. not sure if its from overfilling as Ive not filled it yet. I noticed a yellowish mess in the well and blamed the wifes cats. wont be doing that again.

cheers Stu

stue2
28-10-2010, 02:51 PM
Stu

Yeah I understand your posts.
Just needed to know really if the Top mount on the ram would be above the floor on the inside of the boat, So no inspection hole would need to be cut into the floor for the hydrolic lines... hope that makes more sense

The holes will be well above the floor. If you look under the bait well from inside you can see the bolts from the step. the holes will be just below them. should leave heaps of room.
I have read posts that talk about cutting into the floor but im not sure if I could do that.

where are you located?

Ring Wyld about boats they will sent you some pic. Im not sure if I can post someone elses stuff here. PM me

cheers, Stu

sporty1
01-11-2010, 07:03 AM
Hi guys

went to install my Lenco tabs yesterday. But I have a problem with where to place them on the transom. It is so narrow at the side and with the ladder and a bottom strake I am unsure on what to do.

If you look at the pics I have as a guide taped and marked them on the transom about 200mm in from the side and across a strake on the bottom of the hull.

If I place them any further out towards the side, the bracket on the ram is above the hight of the transom and cannot be attached. The boarding ladder is also a problem. I have the 12" x 4" tabs and the short Rams 250mm. I could grind a bit off the bracket on the ram and it will just fit at a wider point but I am reluctant to do this if they will still function in the current position.

Any solutions would be appreciated.