Replace trim tabs on Sea Ray 280

[oysteinhermansen]

The Sea Ray 280 DA comes original with 14x14 (special made) trim tabs by Bennet.

I need more lift in my boat. It has a Volvo KAD300 engine, and it takes a long time to plane.

Any tips about what Bennet trim tabs I can use ? And is it enought to change the plate ?

 

[Tabman]

The Sea Ray 280 DA comes original with 14x14 (special made) trim tabs by Bennet.

I need more lift in my boat. It has a Volvo KAD300 engine, and it takes a long time to plane.

Any tips about what Bennet trim tabs I can use ? And is it enought to change the plate ?

It really depends on the space available on the transom, do you have a picture you can post?

Tom
Bennett Marine

 

[oysteinhermansen]

I have attached a photo of another Sea Ray 280, similar to mine, with the original 14x14 trim tabs.

I see that there might be a problem using wider tabs, but what about longer (14" span, but 16" or 18" length) ?

 

[Henry Boyd]

Melida has already done a tab modification on his 280 w/ KAD. Search for the thread for more details and you might send him a PM to find out what the results have been.

Henry

Found the link to the 280 tab thread:
http://clubsearay.com/showthread.php/26757-Bennett-trim-tab-upgrade-in-280DA

 

[melida]

Melida has already done a tab modification on his 280 w/ KAD. Search for the thread for more details and you might send him a PM to find out what the results have been.

Henry

Found the link to the 280 tab thread:
http://clubsearay.com/showthread.php/26757-Bennett-trim-tab-upgrade-in-280DA

Henry is right.
I did the job 2,5 years ago with the great help of Henry and Dpmulvey(another member of this board did extended his tabs).
To reach the link Henry gave that I started is in the technical tutorial section of this board which needs to sponsoring the site that I'm not currently.
Let me post my pics and what I did here.

 

[melida]

I have attached a photo of another Sea Ray 280, similar to mine, with the original 14x14 trim tabs.

I see that there might be a problem using wider tabs, but what about longer (14" span, but 16" or 18" length) ?

View attachment 25335

Oystein,

As we spoke before we have the exact same boat except accesories added later.

My original tabs were same size of yours.

The magic of extended tabs is side to side increase which is "span", but we have a notch at the transom so only can do span size 40cm.

Thus I went to increase the fore to aft section "chord", did it 50cm.

Stock tabs were 35cmx35cm and then extended 40x50 per side. So increased space 1225 cm square to 2000 cm square did the magic job. I didn't weld onto the exisitings, bought totally new SS sheets and cut, bend, welded stifenings, drilled wholes for zincs. Only used the existing horizontal stifening where the actuator/piston is mounted. And ofcourse leaved the bracket at the transom where tabs are attached.

Did downward stifenings at chord 1cm each side of per tabs and did upward stifenings to the aft "trailing" edge to each tabs. Did rectangular cutting to the front and aft edges of downward stifenning to not injure myself and others relaxing in the sea near tabs and also while using the ladder.

Also did negative angle as describe in Bennett manual to not touch tha tab's aft edge while on plane at a certain drive degree. To do this moved 1-2 cm horizontal stifening where the actuator/piston is mounted. Do the mathfor hypotenus of ractangular how much movement needed. Before doing this while on plane at 3000 rpm and 0 +1+2 degrees ofcourse fully retracted tabs still touching to water and reacting as lowering the bow and jumping like dolphins.

Also did 3 rectangular stifennings from piston stifening to aft edge for extra support of huge tabs.

Here are the pics of processes I've done.

Before doing the aft and rectangular stifennings and negative angle, just side's downwards.

.

Then did the final fine tunings and happy with them since feb 2010.

Please forgive me for this quick and complex post.
You have my email and also can reach me from skype and wiber if you need more real life experience.
Have a nice sunday and fathers day if you have children.