Trim Tabs??

[leezor]

Hi Everyone,

Am throwing the idea around of fitting trim tabs to my Southwind SF20. Didn't really think much of it, but the 200hp Yamaha I just replaced had a Stingray foil attached to it.
Since having the Suzuki 4 stroke fitted I am experiencing porpoising, it seems to be more evident when the seas are calm and there is a slight swell.

Am guessing the foil was fitted originally to fix the same problem, I did notice a crack had been welded around the cavitation plate which I assume was caused by the foil so would rather not fit one to the Suzuki.

Has anyone experienced this problem before, and by fitting trim tabs was the problem resolved?

Cheers,

Lee



Since having the 4 stroke fitted I have been experiencing porpoising which The 200hp Yamaha I just replaced with the Suzy 4 stroke had a

[Monza]

Go with the tabs - they will transform the boat. I didn't think I really needed them until I put them on to correct listing and found they are versatile in so many other different situations including porpoising in smooth water. I fitted the Bennet M120 electric hydraulic sports tabs on my 6m fibreglass.

[leezor]

Thanks Monza, do you have the positioning sensors fitted aswell?
I was reading on the Bennett website that tab position can be displayed through a GPS via the NMEA feature, has anyone used this feature?

Lee

[Baycruiser]

Fitted a set of bennett 12x9's to my c/craft 575 explorer. Made a big differnece to ride and listing. Always have them down to some extent, even in smooth water as I have found it flatens the ride out and stops porpoising. Also, the rougher the conditions and the stronger the cross wind, the greater improvement in ride over not having tabs. Definitelt recommend fitting to 6m deep V glass boats.

[Kiktz]

Dont know how you love with out them.

A mate had the same problem wioth a 6m Alloy, Tabs fixed it straight up.

Aj

[ozscott]

Mate I have the same tabs as Monza on my 70s 21 foot vagabond. I put them on and the difference between that and the situation where I had just a SE Sports foil in truly amazing in all conditions. I would never own a 6m or over boat without them now!!!!!!! They are easy to fit yourself. You wont need a position indicator - you know very quickly where they are by the trim of the boat and feel.

[Monza]

Positioning sensors are probably nice to have, however you quickly get a feel for where the tabs are from the way the boat responds. When I'm using them, I've found I use them in one of 4 modes.
1. One tab lightly down either side - correct list into wind or with uneven load
2. Both tabs lightly down - good for high speed running to control bow lift and porpoising and keep boat running flat
3. Both tabs down when taking off and retracting up when up to speed - good for popping boat out of hole with heavy rear load.
4. Both tabs down hard while running slow - great for lifting the stern at low planing speed into rough water - will actually save up to 25% fuel and keep boat level through large chop and waves.

Note in most cases (except for 4) then tabs may reduce fuel economy by 5-10%, depending on how far down they are.

[just_cruisin]

Sounds as though that little bit of extra weight of the 4 stroke, has effected the overall ballance of your boat, I agree tabs would be the best solution.

[crazboutfishin]

Leezor,

Tabs will do the trick. But then you have the descition on which ones to get. My vote is the QL trim tabs from Volvo Penta. These tabs are amazing. They sit flush on the stern and dont stick out like other tabs such as Bennets. They have a much beter control panel which allows more detailed adjustments to be made. But in the other hand it is easier to read and undertsand. They are an instant reaction. This is becasue they are not a horizontal plate which moves down. These tabs have a vertical plate which drops straight down into the water. We have run them on our trailcraft 570 Crossport which they were amazing on and we will be running them on the new Fisher. Good luck with the choice and make sure you give these serious consideration.

Photo has been attached

Cheers
Crazy

[ozlongboarder]

I need to fit some tabs to my Bertram 25. How much are the QL tabs?

[crazboutfishin]

Ozlongboarder,

The QL's are around $1000 fitted. What you may need to ask though is whether you will need to put 2 on each side because i know it depends on the hull length and weight. Sometimes on the bigger boats 2 on each side is required. Im not sure if yours will require that or not. Make sure ask them though.

Cheers
Crazy

[Kiktz]

Just cruising the extra weight of the 4 does affect the weight of the boat.
'
I can say that now first hand and i am happy that we kept to the same engine weight (or as close as we could) so that we didn't affect the ride of the boat. In the same breath i am glad we have tabs as there is no affect
if anything the boat rides better.


Aj

[ozscott]

I checked out those Volvo tabs a while ago - they are like the design that fast ferries etc use. The trouble that I saw with them, apart from the price, was that they were made of polycarbonate and had nowhere to go if they were down and were struck by a hard object such as a log - whereas the tabs are on a less vulnerable plane and would move up most likely against the hydraulic pressure - that was my take and I might be wrong, but thats my 2CW. Having said that have a look and check out of Volvos because the design is very effective.
Cheers

[leezor]

Thanks guys, Looks like trim tabs it is, now just gotta decide which ones to get. The QL's look interesting, will look furher into them with our local Volvo dealer.
The dealer who fitted the new engine has recommended the Bennetts M120's and from memory I think they are the Volvo dealer aswell so will quiz him on the QL's tomorrow.

More bloody money to spend on the boat, maybe it's time to find a new hobby!

Cheers,

Lee

[mirage]

Gday Lee,

I put the QL's on my 6.4m Freedom Seasport with a Suzuki DF175. The boat wasn't porpoising but the bow used to slap down hard off the top of a swell.
As mentioned above they are very simple to fit and operate and they fixed my problem as well as I could expect. They are great in a crosswind or beam sea as they operate together not independantly so it is very easy to get the boat on an eaven keel. They come standard with a position indicator on the small control panel. All in all a quality piece of kit.
I think they cost about $890 and I fitted them myself in a day. A word of warning though, you will need acess inside the boat, low down on each corner of the transom.
Another great thing about them is they don't stick out far at all so will not get in the way of boarding ladders and you will not cut a fishing line off on them.

Cheers, Scotty.

[Wear_the_fox_hat]

Lee,
I just put some Lenco electric trim tabs on my boat & find that they also are great. The reason I went for them is because there isn't any need for a hydraulic pump etc.
Question for all on the QL tabs: Would they create more drag by just driving straight down into the water compared to normal trim tabs???

WTFH

[crazboutfishin]

Wear the fox hat,

That is something we considered but we found out that it actually doesnt. We did a little test by cruising at 25 knots and dropping them completly and we only lost about 2 or 3 knots. They are really a great piece of craftesmenship.

Cheers
Crazy

[Chimo]

I'm with WTFH,

Lenco elec tabs no hydaulics and work a treat with foils on both motors as well, lifts up as quick as you want and lot of adjustments to fine tune.

Chimo

[ozscott]

so youre keeping the foils on then Chimo?

[mirage]

WTFH,
Aparrently the QL tabs create less drag and thus are more efficient. As the blade lowers into the water they create "lift" in front of them producing an upward force on the bottom of the boat rather than an upward force behind the boat on conventional tabs.
For normal operation the most I need to lower my tabs is to the second setting, there are 7 different positions with 7 being full down. At the second position the tabs would only come down into the water about 7mm to 10mm, not very far at all.

The Volvo Penta Website explains most of this in th QL section.

Cheers.

[leezor]

WTFH, out of interest what size Lenco's did you end up installing and how are they priced compared to the Bennetts?

Was quoted $800 for th M120's plus around $200 to fit them tho will be installing them myself, looks like a fairly simple install.
I also questioned the dealer on spare actuators fror the Lenco's, $320 will get you are replacement one if it ever fails.

Am still no closer on deciding which ones to get tho, they had both in stock and said both had there advantages over the other.

Cheers,

Lee

[Chimo]

Hi Oz

Yes I thought about it but the way things are set up and with the slow steps I took in fitting bits one thing at a time I decided
1 I wanted to keep the lift I get with the foils that results in a lot less water being thrown around at the sides at the stern (at slow to medium plan speeds in the rough offshore pre the foils the water started to feel the SFarer label off on one side, now there is no wash any where near that height) and

2 I still have the side to side levelling and and the lift I get from the Lencos.

3 I also effectively have a longer boat ie the extra length of the Lencos even when they are fully up and thats a benefit too

So there you go :D

Cheers

Chimo

[mark221263]

I can understand the claims of the QL tabs but one advantage I see with the bennett and lenco's is that you actually lenghten the planning length of the boat which has additional benifits.

I'm currently considering a pair of tabs for my boat and are still trying to decide what type to get. I like the simplicity of no hydraulics but then the lenco's have electric screw motors out in the open, a leaky seal and there a gona.

????

[leezor]

Has anyone fitted tabs to a transom that is stepped? The attached pic is the same hull as mine and am wondering if the step will hinder the performance of the tabs.

Cheers,

Lee

[Chimo]

Hi leezor

Sure have

Chimo

[Chimo]

Stbd Lenco and burley bucket and step

[Chimo]

Tabs and Foils and triducer Rakers (on a fishing boat :-X) etc

[leezor]

Hi Chimo, I was actually referring to the step on the underneath where the water flows. Have since modified the last pic to point out what I mean.

[Chimo]

Hi leezor

I understand, but I think you would still mount the tabs on the hull as close as practical and as per the directions to each side with the ram thru the "climbing up on step" If you were to use Lencos and you can use whatever you wish, I dont sell em, there is only one power lead to run to the controls. That suited me and no more hydraulic oil in the boat.

Chimo

[leezor]

Chimo,

Yeah, the Lencos sound like the go mate. I think if the boat was moored permanently I would be concerned about the electric actuators and go hydraulic.
Thanks for your help, will let you all know how they go when I get them.

How much did they end up costing you?

[Chimo]

PM sent

Chimo

[Shanoss]

I'll sell you mine Lee. No fancy switches, just good 'ol elbow grease. minus oil though. you cant have the oil

[leezor]

Couldn't do that to ya mate, those things must be a collectors item by now. Am sure Noah used em back in the day. :P

[Shanoss]

And you can be sure they dont make 'em like that anymore. miay have to try and resurrect them i think.