How do you "dial in" a 50 inch mono?

[jcald2000]

Several things to check!
1. Are you sure your collets aren't slipping, sure sounds like it?
2. Are the ends of the cables soldered, loosen the collets and slide the flex out enough to check? Put grease on the threads of the collet nut to get more torque on the collet nut.
3. On your radio turn the servo throw down to 50% and add 100% Expo. If the radio can't do that all you can do is move the servo end rod to closest hole to the horn screw to cut down the throw. The rod is least a 440 or 3mm ROD isn't it?
4. Have you calibrated BOTH ESC's to the radio?
5. Is you servo at least Digital and 209 in. oz of torque?
6. How are you powering the servo?
7. On the last video at about 45 seconds when your hand is on the radio you start the turn slowly then flick the wheel over harder. Your turns with this power should be twice the diameter.

Please answer all the questions and we can get this dialed it for you!
We have all been there!

[iop65]

never owned a twin drive but i've been told that a twin mono never turns the way a single drive can turn :makes sense because i've seen twin mono's in saw runs and never in races!

the explanation is that the boat leans in the turns and by doing this one prop comes out off the water and looses thrust , boat becomes very unstable
you should get off the throttle and make wider turns with a twin mono
what could help a little is having trimtabs on the outside , this prefents the leaning a bit

so i guess that his collets aren't coming loose ne prop is less deeper in the water and the motor revs up ( can be heard in the video's)

[Make-a-Wake]

I would run the props spinning outward, counterclockwise on the port side etc..................

[Andrewc]

Many thanks to all who have responded so quickly. Thank you.

Firstly Jcald2000:

1 I dont think the collets are slipping.

2 Ends are soldered but I have ordered some Loctite to put on the ends of the flex shafts. Tried soldering an off cut, the result wasnt good!!

3 Will adjust settings as suggested.

4 Used the programming box to calibrate the Escs. They are then connected to the receiver via a duel cable going down to one which goes into the receiver.

5 Not sure if the servo is digital but it has 16kg of torque which is probably slightly above what you suggest.

6 The servo is connected directly to the receiver. The receiver takes it power from a BEC via one of the ESCs.

7 Need to have a look again at the video but overall I would say the turning circle is quite large.

Cheers

Make a Wake

When I first tried the boat I had the props turning counter clock wise and was advised to have them turning clockwise which I have done. Cant say that I saw any difference,

many thanks

[tlandauer]

The best way to ensure MAXIMUM grip on the flex cable by the collet is to use anti seize compound: http://www.permatex.com/products-2/p...bricant-detail
Put a bit on the threads and prong and you will see how much further you can tighten the collet. No more metal galling, extends the life of the collet.
I am just passing on a trick I learned and am not questioning your assessment of the collet situation.
Cheers!

[madmikepags]

With twin monos and surface drives one prop will always unload in the corner and conversely the other will submerge, thus the draw on the motors batts and speedos will be very different on each side. the way I have done mine was to use struts and not stingers that way I could run stuffing tubes outside the hull on each side and drop the props lower into the water slightly below the keel. You will now have slightly submerged drives but the draw on each motor will be closer to equal, you must also alter prop sizes from surface drive and must run them counter rotating because now you have much more prop in the water and will experience much more prop walk. There are also some very cool things you can do with mixing on the radio like when you turn left you can make the right speedo go to 50% (or whatever % works) and vice versa. just some ideas????

[Rocstar]

When I first tried the boat I had the props turning counter clock wise and was advised to have them turning clockwise which I have done. Cant say that I saw any difference,

You're not running counter rotating? Spin the props outwards and make wide turns. Spinning them in will give you more life and straight line speed, but turning will be sketchy with a step hull. My 59'' Outerlimits had similar issues. Never could make sharp turns.

Edit: I see in your first post, they are counter rotating. Still, try running again with them spinning out.

1:53 to see it run from the dock.

[Andrewc]

Thanks Joel. Sorry I must have been having a senior moment. The props are counter rotating and I changed them from spinning in to spinning out and it doesnt seem to make any difference. It suddenly spins out when it is going in a straight line and I havent touched the steering to make it corner. I have ordered some anti seize compound. Hopefully this will either confirm or otherwise if the collets are slipping or not. At least it will be another thing to tick off the list as not the problem.

I have attached another couple of videos and hopefully this will help other professionals out there to give some advice. Make thanks everyone.

https://www.youtube.com/watch?v=6xDiC28rdN4

https://www.youtube.com/watch?v=SBU54ujrQUI

[Rocstar]

Two things. Make sure you have a strong servo and where is your CG? It looks like it's bow steering. Any pictures of your layout inside?

[Andrewc]

Hi Joel

Too late now, but will get on the case of interior shots etc tomorrow. The cog was around 30% and then I moved it way forward which seemed to make no difference to it spinning out.

Cheers

[Make-a-Wake]

I see in your first post, they are counter rotating. Still, try running again with them spinning out.

Hmmmm, that's what I said several posts ago as well.

PLUS he mentions: "When I first tried the boat I had the props turning counter clock wise and was advised to have them turning clockwise which I have done. Cant say that I saw any difference"

You cant run them both the same direction which is what your comment can be construed as

[Rocstar]

Hi Joel

Too late now, but will get on the case of interior shots etc tomorrow. The cog was around 30% and then I moved it way forward which seemed to make no difference to it spinning out.

Cheers

Moving the weight forward will make it worse. Get the weight back as far as you can and start over from there. Small adjustments at a time. My Outerlimits was touchy and would bow steer like that with the weight forward. If you're still having the same issue with the weight back, you may need to look at other options like props with less lift or a little positive angle on the drives.

[MarkF]

Joel is right. The boat is bow steering which means it's nose heavy. It also looks like way to much rudder throw.

Mark

[Andrewc]

Pictures as promised. The Cog is around 28 to 30%. I can only reduce it more by moving the 3 cell packs so they are either side of the motors and they can be pushed back as far as the transom. Alternatively I could just add some weight to the back until I find out if this is the problem.DSC04551.JPGDSC04552.JPGDSC04553.JPGDSC04554.JPGDSC04555.JPG

The rudder is a 2 inches below the keel and the turn fins are about 2 inches as well. I cant lower the rudder anymore but I can lower the turn fins if I change to a slightly smaller trim tab. Would this help?

[Andrewc]

More pictures.DSC04556.JPGDSC04557.JPGDSC04558.JPGDSC04559.JPGDSC04560.JPG

When you say "a little posotive angle on the drives" Joel do you mean I should lower the prop end. The stingers are currently flush/inline with the keel.

The last picture shows a yellow battery pack. This is only to show how far back I could get the three cell batteries. Another thought, is it worth running it on 6 cells per motor as this might be a quick way of determining if it is the Cog which is the problem.

Many thanks.