What did I do

[produceguy]

Re: What did I do

What is a stingray fin? Got a pic?

 

[airshot]

Re: What did I do

FYI...I have made my own tail fins in the past, many times for different boats. Just picked up a pc of SS sheet metal approx .060 thk, even used
.040 for an ob motor once. just cut and trim to 2-3" wider per side than cav plate and allow about 2-3" to stick out the back. Last 3/4" make a slight downward bend then trim out to fit around lower unit. Use 4 small ss screws to attatch to cav plate ( attatch to bottom side) This thin plate will add such a minute amount of drag you will never know it, on 3 of the four I have made it improved plane speed and top end speed, one unit improved plane dramatically and lowered top by 1 mph.
The plastic bolt on units are way to thick and do add alot of top end drag but the thin sheet metal plates do have a noticeable effect on top end but do give additional lift at low speed. Will be making one for my Islander over the winter.

Airshot

 

[produceguy]

Re: What did I do

airshot, Sounds like you know what your doing but something is telling me not to even try it. Maybe if I had more experience and knowlege I might. Send a pic if you can, It would help me. Can I buy the sheet metal at Lowes or Home Depot?

 

[dockwrecker]

Re: What did I do

No NO NO! No stinkin fins! Stingray fins are the same thing as Doel fins. GET TABS!

 

[produceguy]

Re: What did I do

You got it dockwrecker. After that prop, Youll be my boat mentor, If you dont mind.

 

[dockwrecker]

Re: What did I do

Glad to help!

 

[JupiterJoe]

Re: What did I do

Hey dockwrecker a question to you
I have followed this post and heard your views on all the fin add ons. I added a set to my 27 Tiara with twin mercs I/O 290hp 350s. after I installed them I got a better hole shot gained 3mph at cruise kept my WOT 40mph and no change in fuel usage. I didnt change props or anything else. I do have a set of Bennett trim tabs that have been on the boat since day one. And on my other boat I recived better hole shot with a single OMC I/O . Just a question not a smart ***** remark.

 

[dockwrecker]

Re: What did I do

I don't know what you've got for Bennett tabs or if you know how to use them. Maybe they're undersize, it doesn't sound like you had them installed as you state they were there from day one. Not enough info to say one way or the other. Given the size of your boat, (and I've had more than a couple that big) I'm half betting you find it difficult to find proper balance with the hydraulic tabs. Not the tabs fault. If they're not the right ones, they ain't gonna work, and if you're unfamiliar with using them, maybe confusing also. Get back to us with your tab dimensions and operating conditions, maybe we can discuss this further. Tabman I'm sure will be helpful also. Your boat will handle MUCH better properly equipped, and with experience, will deliver improved handling and stability in rough conditions. Fins aren't speed adaptable, thus my biggest knock on them, and as per my earlier post, a handling compromise for higher profile boats such as yours. I'd also suggest looking at your load balance. A 60 quart cooler loaded up in the stern doesn't help much. A fin is a fixed lift device. It isn't hull or load specific, and can't adapt the way hydraulic cabs can to various conditions.

 

[JupiterJoe]

Re: What did I do

The tabs are a 9x12 , and I am very familiar with using them how they work ect.
I have been on boats my whole life. I fish,run and play off the south east fl coast. the boat does handle better in a choppy water rather than calm flat water. I load my boat proper, coolers as far foward as posiable. It is a cabin crusier, Fishing boat. (almost like a small sporty) It also is a 9000lb boat loaded.

 

[dockwrecker]

Re: What did I do

9 X12 is WAY undersize.
Sizing guidelines from Bennett:


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What size trim tab is right for me?

Many factors affect the choice of properly sized trim tabs, and the ultimate responsibility for selection is up to you, the boat owner. To help you decide, Bennett Marine offers you a few guidelines below. If you still have questions about the size you need, just contact us and we'll be happy to walk you through it.



General Guidelines
These sizing recommendations are based on average performance. Your choice may vary based on power, engine configuration, weight distribution, type of boat, and use. The greater the surface area, angle of deflection and/or speed of the water flowing under the trim tab, the greater the lift.

When making a choice between trim tab sizes, remember that the largest trim tabs that will comfortably fit on the transom will be the most efficient.

As a rule, choose at least one inch of trim tab span (per side) for every foot of boat length. (Examples: 22-foot boat = no less than 24" x 9", 36-foot boat = no less than 36" x 9".

Span = side to side measurement
Chord = fore to aft measurement

Whenever possible, choose a 9" chord trim tab, and gain lift through a longer span. The span of the trim tab has more of an effect on the amount of lift. However, a longer chord can be used effectively, and there are situations where you may need to use a 12" chord. Click Here to See When to Use a 12" Chord



Measuring
Choose the approximate tab size for your boat using this sizing chart. Make sure the tabs will fit your transom using the diagrams below as a guideline. When measuring, disregard the strakes and follow the Vee of the hull.

Boat Length Engine Configuration Trim Tab Size
(span x chord)
15'-19' (4.5-5.8 m) Single I/O, Single Outboard or Inboard 12" x 9" (30 x 23 cm)
17'-19' (5.2-5.8 m) Single Outboard 8" x 10" (20 x 25 cm) M80
19'-24' (5.8-7.3 m) Single I/O, Single Outboard, or Inboard 18" x 9" (46 x 23 cm)
19'-24' (5.8-7.3 m) Limited Transom Space or Extra Lift 12" x 12" (30 x 30 cm)
20'-23' (6.0-7.0 m) Single I/O or Single Outboard 10" x 12" (25 x 30 cm) M120
22'-27' (6.7-8.3 m) Single I/O or Single Outboard 24" x 9" (61 x 23 cm)
22'-27' (6.7-8.3 m) Twin I/O or Twin Outboard 18" x 12" (46 x 30 cm)
25'-30' (7.6-9.1 m) Single I/O or Outboard 30" x 9" (76 x 23 cm)
25'-30' (7.6-9.1 m) Limited Transom Space or Extra Lift 30" x 12" (76 x 30 cm)
25'-30' (7.6-9.1 m) Twin I/O or Twin Outboard 24" x 12" (61 x 30 cm)
28'-34' (8.5-10.4 m) Inboard 36" x 9" (91 x 23 cm)
28'-34' (8.5-10.4 m) Limited Transom Space or Extra Lift 36" x 12" (91 x 30 cm)
28'-34' (8.5-10.4 m) Twin I/O or Twin Outboard 24" x 12" (61 x 30 cm)
32'-38' (9.7-11.6 m) Inboard 42" x 9" (107 x 23 cm)
32'-38' (9.7-11.6 m) Limited Transom Space or Extra Lift 42" x 12" (107 x 30 cm)
36'-44' (11.0-13.4 m) Inboard 48" x 9" (122 x 20 cm)
36'-44' (11.0-13.4 m) Limited Transom Space or Extra Lift 48" x 12" (122 x 30 cm)
42'-50' (12.8-15.2 m) Inboard 54" x 9" (137 x 23 cm)
50'-60' (15.2-18.3 m) Inboard 54" x 12" (137 x 30 cm)
60'-65' (18.3-19.8 m) Inboard 60" x 12" (153 x 30 cm)
65'-70' (19.8-21.3 m) Inboard 66" x 12" (168 x 30 cm)
70'-80' (21.3-24.4 m) Inboard 72" x 12" (183 x 30 cm)

No wonder you don't care for them...

 

[xxxflhrci]

Re: What did I do

Yeah, I know fins are evil around here, but I put on on my boat.....I broke that same piece off of my boat once, except the chunk was larger. A trip or two later, I picked up a stick or somthing and it got thru up there and bent the repair up. I heated up the repair and bent it back straight. I put the Stingray on to make the area stronger and less prone to damage. Anyway, since then I haven't had any more damage. I couldn't tell any performance gain or loss from the Stingray.

 

[Alpheus]

Re: What did I do

Every time I buy a boat to scrap out almost 99% of the Bayliner owners put those darn fins,tails and junk on their outdrive. I have a pile of those things.

Here is a pic of the last one I just bought last week.

It will be going in the scrap pile as well...

 

[xxxflhrci]

Re: What did I do

Dang, I wish I would have bought a Bayliner. I could have probably saved 25 bucks.

 

[honeys money]

Re: What did I do

WOW, "Al" glad I didn't buy a Bayliner, I would have had to start me a pile, I like my whale tail or fin what ever yall call it, I have had the same boat with and without it, I prefer with it.

 

[JupiterJoe]

Re: What did I do

[QUOTE9 X12 is WAY undersize.
Sizing guidelines from Bennett:

][/QUOTE]
I missed measured they are 11x12 and due to the hull desighn and placement of the I/Os
I dont see a bigger one working

 

[dockwrecker]

Re: What did I do

Well at best case given the Bennett guidelines, you're at 63% of the suggested tab size, and running the way you say you're loaded up, 118% under the recommended tabs for your stated load. Keep your fins if it makes you happy, but the fact remains you've got the wrong tabs and a band-aid fix going on back there. If you think 37% larger tabs at a minimum is insigificant, that's your call. It's your boat. Enjoy.

 

[JupiterJoe]

Re: What did I do

25'-30' (7.6-9.1 m) Twin I/O or Twin Outboard 24" x 12" (61 x 30 cm)

That seems way to big I only have a 10' beam. 48'' of tabs where would the drives go? They have to turn. Wow well she rides nice maby I'll take off the fins next trip and see how she rides. Its only 8 lil bolts. were is it you find all those specks? Thanks dockwrecker

 

[5150abf]

Re: What did I do

To check the prop just take it off and use a tape measure from the back of the hub to the tip of the blade, there will a be a bit of variance but close enough to see if it is bent.

As to the damage, you can fix it or not, I really doubt that will affect the boat at all, just be careful who you take it to, if the guy can't weld pretty good it may turn out 10 times worse, cast is pretty tricky to weld.