Trim tab or Not to trim tab ! that is the questions !

[ram750]

I guys ,

I am fairly new to the forum but I have found very good help surfing thru the topics...

Anyhow I now own a 21' Baja 210 Ess / Sport and the boat rides really nice ... I get about 61mph perfectly trimmed. I would like the boat to ride a little straighter in cross current situation and then also when friends are all loaded to one side but the main and most important thing I would like to correct is porpusing. I think from my research that I have pretty much all the right reason to install some Tabs.

I found a set from an older boat they are nice and wide but not really much chord to them , i needed to know if this is less desired for a faster application boat like mine.

I have read enough about installation and usage on the average size boat and speed but just wanted to confirm those would work for my application.

Let me know what you think !

Thanks

 

[Bamaman1]

Re: Trim tab or Not to trim tab ! that is the questions !

Hydraulic trim tabs will do the job for you--lateral leveling and stop porposing.

We just seldom see them on such high performance hulls, as not many "friends" are usually carried on a boat that runs as fast as your boat.

You might want to talk to the manufacturer's customer service dept. to make sure you get the correct length and model.

 

[QC]

Re: Trim tab or Not to trim tab ! that is the questions !

They're on every high end go fast where I boat . . .

You want more chord than width for higher speed apps.

 

[Tahorover]

Re: Trim tab or Not to trim tab ! that is the questions !

Make sure you install them correctly!

found on E-bay

 

[DJ]

Re: Trim tab or Not to trim tab ! that is the questions !

They're on every high end go fast where I boat . . .

You want more chord than width for higher speed apps.

It's intersting.

My Brothers 26' Crownline (7.4L MPI/Bravo III) has them. He has NO idea how they work.

A couple weeks ago, I got some time, in the boat. Using them, he was astounded at how much better it rode and its attitude (bow high/low and balance).

With them, I can keep that very heavy boat, on plane, at 2500 RPM and just over 20 MPH throwing a very small wake. ( I wish others knew this) Or, I can trim the boat-side to side-perfectly at 50 MPH+-bow high with just a few wetted feet of the hull, in the water at 4600 RPM.

I've tried to teach him but it seems to be beyond his interest level.

Trim tabs are a Godsend for a heavy v-bottom boat.

 

[Tabman]

Re: Trim tab or Not to trim tab ! that is the questions !

Ram750,

Can you tell me what size they are and what make? Trim Tabs can be a great asset on a boat like your Baja, but care needs to be taken to make sure that the Trim Planes are suitable for a boat that can go as fast as yours. A picture of the Trim Planes would be great if you have one.

 

[ram750]

Re: Trim tab or Not to trim tab ! that is the questions !

Thanks for all the answer's ! Very appreciated.

For the Trim tabs I am not sure of the dimension but they where on a 25' Cruiser... I wil go and measure them later today.

The thing that made me ask the question is that I did notice that most fast hulls where equipped with long skinny trim tabs , lots of chords and tapered and not that wide... I guess that has something to do with the drive configuration too but wanted to know if it was related to high speed use also ?

this is my boat BTW , its not a real deep V but it has a substential V to it !

 

[skargo]

Re: Trim tab or Not to trim tab ! that is the questions !

I love my Bennets, they make a huge difference. I boat on the Chesapeake, where conditions change all the time and they are invaluable!

 

[Tabman]

Re: Trim tab or Not to trim tab ! that is the questions !

Long Skinny Trim Tabs are indeed found on a lot of go fast boats, and there are a couple of reasons for this.

Often these boats have twin engines or triples and the space is limited where Trim Tabs can be mounted. The really long Trim Tabs you see on racing type boats are really used for different purposes than most recreational boaters use theirs. These racing type Trim tabs are used for stability at higher speeds, they are most often mounted a little higher up on the transom so that when they are deflected the smaller tapered trailing edge of the Tab contact the waterflow first. This allows small corrections to be made at high speed with very little drag. The long tapered shape also functions sort of like a wheelie bar; as the bow raises the back end of the Tab contacts the waterflow, produces a little lift and stops any further bow raise. This is very effective in deducing porpoising at high speeds. Also when the boat launches off a wave at high speeds the bow often goes up dramatically and the long Trim Tabs will contact the water early in the "reentry" forcing the bow back down.

Most recreational boaters are looking to hold the bow down at lower speeds so the boat rides more comfortably in a chop, as well as balance out side to side trim. "Regularly" shaped Trim Tabs are much more efficient in this regard as less water pressure escapes out the sides as compared to long skinny Tabs. They will still be effective at reducing porpoising at higher speeds, and deliver good control in a variety of conditions.

What I would like to see on Ram750's Trim Tabs is if the sides have 1" upward facing fins. These fins stiffen the Trim Planes and without them they may cup (bend) under the stress of high speed running.

 

[QC]

Re: Trim tab or Not to trim tab ! that is the questions !

Trim tabs are a Godsend for a heavy v-bottom boat.

The only thing I would change is "any V-bottom boat" . . . amazing tool.

 

[skargo]

Re: Trim tab or Not to trim tab ! that is the questions !

The only thing I would change is "any V-bottom boat" . . . amazing tool.

I agree with this assessment.

 

[ram750]

Re: Trim tab or Not to trim tab ! that is the questions !

Tabman , Thank you so much !!! this is not only very helpfull for my application but it also helps satisfy my quench for knoweldge.

The tabs them selve do not have the "rib" on top but I could easily weld some reinforcement on there ( I do stainless ). I will get some pictures tommorow.

Thanks again I do feel better drilling my hull for theses now !

Marc

 

[Tabman]

Re: Trim tab or Not to trim tab ! that is the questions !

Marc,

I am glad I could help.

This is an 18" x 9" with 1" up fins:

It should give you an idea of what I was talking about.

 

[ram750]

Re: Trim tab or Not to trim tab ! that is the questions !

yep ! I know exactly what you are talking about now.

I will tack some reinforcement on mine to prevent the "warping" at high speed !

I will try and complete the install and get you some pics later on.

thanks

 

[palace]

Re: Trim tab or Not to trim tab ! that is the questions !

Check out smart tabs, http://www.nauticusinc.com/

 

[skargo]

Re: Trim tab or Not to trim tab ! that is the questions !

yep ! I know exactly what you are talking about now.

I will tack some reinforcement on mine to prevent the "warping" at high speed !

I will try and complete the install and get you some pics later on.

thanks

Apparently the guy I bought my boat from had bending issues, so he put on the sport tabs with 2 rams.

 

[ram750]

Re: Trim tab or Not to trim tab ! that is the questions !

Check out smart tabs, http://www.nauticusinc.com/

I did but I am not sure about there ability to compensate side to side when off balance...

Also I am getting my hydrolic trim tab set for free ! that helps

 

[Maclin]

Re: Trim tab or Not to trim tab ! that is the questions !

The Smart tabs can compensate some for load balancing but that is not their main bailiwick. From what I can tell about what you want the hydraulically actuated ones are the right choice, just get the right size and strength both for the tab and the actuators. Tabman has you covered I would follow his advice for this.