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feffe
01-18-2008, 12:32 PM
Hi, I´m from Sweden and completely new in the boatworld, I have raced cars for many years and now I want a boat too:)
I was thinking about the supervee I had one last spring and was thinking about getting one again unless you have a better idea.

Now to my questions: When I had mine last it was soooo unstable in higher speeds, I moved my batteries further forward in front of the motor and across the hull and it went liked sticked to the water but am I supossed to do that, that wasen´t the intention from the facory anyway. Is there something you suggest? This is my BIGGEST problem/consern

Does the esc have lvc for lipos?
What prop should I use?, 2 or 3blade?
And how do I balanse it?
Should I get the options trimtabs with screws? and how should I set them up?
What is the advantage with a turning fin on both sides?
Do I need a bigger water intake?
Should I do anything to the hull, polish? it for higher speed or seal it with something so it doesn´t take in water

Like I said, completely newbeginner on boats so any comments, help and tips to help me run a boat good, fun and secure are more than welcome.
Thanks a lot in advance:smile:

hkusp45
01-18-2008, 12:46 PM
Does the esc have lvc for lipos?
What prop should I use?, 2 or 3blade?
And how do I balanse it?
Should I get the options trimtabs with screws? and how should I set them up?
What is the advantage with a turning fin on both sides?
Do I need a bigger water intake?
Should I do anything to the hull, polish? it for higher speed or seal it with something so it doesn´t take in water


Let me first of say hello and welcome!! This is the place to get your answers!

LVC, No this speed control does not have one.

2 or 3 blade: The stock 3 blade seems to cavatate(sp?) alot. Ive been using a CF45 and they work well. Steven for OSE sells them and is quite quick to ship!

Balence: I have found that the batts. in the stock locaton work very well.

Trim Tabs: I have the adjustable ones from OSE and they work well. As for the set up I started with them even with the bottom and did vrey andustments from there.

Turn fins: the only real big advantage would be that they will make the boat turn right and left better.

Water inlet: Stock works well

The hull: I sealed the inside wood and that was about it.

I hope I was able to shed some light for you. These are just my opinons and not set in stone.

Fred

Bill-SOCAL
01-18-2008, 01:48 PM
The SV27 speed control absolutely does have a LVC. The ESC calculates the LVC as 67% of the initial start up voltage it senses when first connected. This can be a little on the low side for Lipos, but as long as you don't actually run so long that it triggers you are OK. In fact, even if it does trip and turn off the motor, you are still OK since it trips at a voltage under load (about 2.81 volts per cell - loaded). Once the load is off the cell voltage rebounds close to the usual 3 volt per cell minimum you see.

This is the aircraft version of the ESC used in the SV27. They are functionally identical:

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXPSY4&P=7

Other comments. The NiMH cells in the stock position balance the boat very tail heavy. This hull would normally balance at about 8.0 to 8.5 inches from the transom (+/- 30%). The stock battery location balances well aft of that point. This makes the boat more likely to blow over.

I've run the GrimRacer 42x55, x442, and x440/3. All work well. The stock prop is not very good at all.

And if you can, use Lipos!! Mine really woke up going from 12 NiMH cells to 4 Lipos (4S1P)

feffe
01-18-2008, 03:52 PM
Other comments. The NiMH cells in the stock position balance the boat very tail heavy. This hull would normally balance at about 8.0 to 8.5 inches from the transom (+/- 30%). The stock battery location balances well aft of that point. This makes the boat more likely to blow over.

I've run the GrimRacer 42x55, x442, and x440/3. All work well. The stock prop is not very good at all.

And if you can, use Lipos!! Mine really woke up going from 12 NiMH cells to 4 Lipos (4S1P)[/QUOTE]

Thanks guys, happy to have found the forum:w00t: . Sorry I am a newbie but how do you mean exactly?
That the balance point is to far back I guess, but what can I do?


yes I am going to use a pair of true rc 5 or 6 a lipo:thumbup1:
Thanks again

Bill-SOCAL
01-18-2008, 04:31 PM
Most monoplane hulls work best if they balance at about 30% to 33% forward of the transom (aft end of the boat). This is just a simple balance like a teeter-totter. The farther back the balance point the higher the boat will ride out of the water. This is good to a point, but after a certain point it is too much and the boat becomes unstable and prone to blowing over backwards/flipping over.

You can get the proper balance point by moving the batteries forward until the boat balances at about 8 inches from the transom. I balance mine a tiny bit behind that point, but 8 inches is a good starting point.

If you run lipos in the SV27 with the stock controller do not use more than 4 cells in series (14.8 volts nominal). More than that and you run the risk of shortening the life of the motor and/or controller.

Mich. Maniac
01-18-2008, 05:22 PM
The SV27 speed control absolutely does have a LVC.

As far as the 67% percent. Take it for what it is. There is a reason Grim and AquaCraft have stated that this esc does NOT have a lvc. Because it is basic and will not cover all situations properly.
__________________
This was agreed upon and directly stated by Steven. It is not to be considered a LVC. I agree. Always stick with what you know and things run smoother. External is the way to go. Just another mans opinion.

Bill-SOCAL
01-18-2008, 07:22 PM
Like I noted it is crude and will give a lower than ideal cutoff. I simply time my runs with it and have never gotten close to a LVC situation. My average run is 4.5 minutes WOT

Chop
01-19-2008, 12:36 AM
Hi Fred and welcome!

I too am new to FE boating. In fact I purchased a SV here about a month ago. It is cold here, the lakes are iced over and my boat will probably not see water for until the end of March.

This is a great forum and I will be watching this particular thread closely.

WELCOME ABOARD!!

feffe
01-19-2008, 05:14 AM
How exactly did you do to balance it right? How did you move the batteries?
Of course I not going to run more then 4lipo cells:smile:
Did you have any problems with the heat when you run lipos?
And so what shuold I get replaced.
Sorry for all the dumb questions but thanks you all help guys:D , you rock:buttrock:
Fredrik