Turn Fin placement for Hydro Vortex? - help please

[Fade2Gray]

Hi Everyone,

I have just purchased the aquacraft turn fin (http://www.offshoreelectrics.com/pro...od=dh-aqub9515) which l am wanting to call upon the experts out there to ask about the correct placment and attachment of the turn fin onto my Vortex. I must admit the new aquacraft turn fin looks huge and alot thicker than my current thin stainless stell turn fin (as per the attached photo).

I would love to hear from people who currently have a Vortex and some pictures of your boat's turn fin setup, this would explain things very quickly i.e. picture tells a 1000 words

Please see attached my current turn fin which l am planning to replace for the new aquacraft one.

I have also attached some photo's of my setup, l am looking to replace the rudder assembly, would love to hear any recommendations here.

Thanks in advance.

[OJ racer]

I have a vortex, I went witn the Solinger hydro hardware from OSE, it is great quality and has a built in water pickup.

Your stuffing tube looks a little sharply angled, if you can I would recommend putting a slight bend in it.

I have the same turn fin as you, but I mounted it pointing straight down. I bent mine once, but it's so flexible that it bent back easily.

Hope this helps!

[OJ racer]

Here's some pics of my setup:

[Fade2Gray]

Thanks for the info and photo of your setup.

With regards to my current hardware setup, l don't think l would be able to use the Solinger harwdare as hole for the linkage boot is on the left hand side. The Solinger harwdare is angled/curved to right.

With regards to stuffing tube, l take it that it's the tube where the flex shaft is inserted into (sorry for noob question) - If so, if l were to bent this at less of an angle it would mean that the prop would sit up higher which might effect the performance?

I noticed that your turn fin is completly flat as mine has a bit of curve. I will see if l flatten this or simply install the new aquacraft fin as previously indicated but this much much larger.

BTW: Do you get much or any water insiude your hull?

What sort of speeds and run times are you getting?

Thanks again :)

[Raydee]

If that turn fin is flexing then it is useless, it will make your hull do all kinds of funny things in the water.

[10gauge]

Raydee is right. I am also in the process of building a DF22 Hydro. I had questions regarding turn fins too, and I'll quote what Jay T had suggested for a similar sized hydro, like the Vortex. I value his good judgment and vast experience.

For a similarly sized hydro, he recommends that the turn fin be extended at least 1.25" below the water line and be about 1.25" wide. He uses a 1/16" aluminum sheet. The fin should be slanted in towards the center of the boat about 5-7 degrees. More than that can cause poor handling.

[OJ racer]

I'll do my best to answer your questions.
The stuffing tube is the brass tube the flex shaft goes through, if you bend it to enter the hardware near straight in, it will lower flex shaft wear, streamline it, and probably allow higher rpms. I'll include a picture of mine.

You definitely want a flat turn fin. I hit a stick and bent mine once, until I fixed it the boat had all sorts of handling problems, mostly that it constantly turned right. Or as it appears in your case left.

I am getting some water in my hull, not too much. I put a small sponge in it, water proofed my reciever, and elevated everything else. I learned a way on this forum to waterproof the stuffing tube by slipping a bit of nylon tubing over the top of the stuffing tube. I'll include a picture of that too.

With an x432 and 14 nimh cells in series, I was getting about 40, but I upgraded to a new prop now. I'm waiting for OSE to reopen so I can order batteries that won't melt with my new prop, an x440. So far with 7 cells driving it I have gotten 28.8 with the x440. That means about 48 with 12 cells, which is what I'm getting. Run times, with the seven cell batteries about 5 minutes. Not great, but fun anyway.

[OJ racer]

Oops, forgot the picture.

[OJ racer]

Sorry, I couldn't get a good shot of the top of the flex shaft.

[Fade2Gray]

Thanks OJ racer, l appreciate your responses and photo.

Looking from the back of the Vortex what side is your turn fin on ?

Here in Asutralia, we run our boats in a oval clock-wise direction, having said that should the turn fin be mounted on the left or the right (when looking from the back of the hull to the front) Most of the turn fins l have seen in forums have been mounted on the right hand side (again looking from the back of the hull to the front)

Would you recommend that l use the recently purchased aqaucraft fin, it's a lot larger than the current fin as l have pictured?


Thanks again

[OJ racer]

In the vortex, the transom of the right sponson is reinforced for a turn fin, so keep it there. That's where mine is. I think you could go with it and use that fin, but if you drive clockwise definitely tilt it in, not out. Tilting the fin out turning clockwise will actually make the fin be more prone to lift out of the water, in a high speed turn possibly even flipping the boat. I tend to do both, so I kept mine straight.

[OJ racer]

Anything you need to know is on this forum. Everything I know I've learned through common sense and this forum. Thanks to all the guys who help each other out!

[Fade2Gray]

I have attached two photo's showing different angles of the turn fin mounted to the hull.

Can you please advise which angle that l should be using using the two supplied photo attachments

[Fade2Gray]

Whoops, here they are.


Thanks again, l appreciate your help

[G Doggett]

The L/H picture will work if you must use a curved fin, the R/H picture will never work.
I prefer to use a straight fin but angled in between 5 and 10 degrees.
The fin must be strong enough to handle several times the boat weight without bending.
A crude but effective test is to pick up the boat by the turn fin only and shake it up and down.
If the fin bends throw it away and fit a stronger one.
Graham