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Scale Ballast

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colin:
                           BALLAST AND TRIM IN PERFORMANCE SCALE MODELS.

You have all heard the "expert", “Long thin models do not sail”,?  “ will not steer “etc, WRONG. See our video, it was made to prove it can be done, and we do.
The Royal Navy have been doing it with long, narrow beamed, ships for many  years.

One of the problems is the belief  that adding more ballast will correct this percieved instability.
I am afraid that it seldom has anything to do with that.
If the model is correctly ballasted to the LOAD WATERLINE, and rolls evenly when disturbed, then ballast is most probably not a problem.
The main cause of instability of Warship models is by OVERDRIVING the model, let me try to explain.
All displacement ships (model, or real, have a designed waterline speed,) i,e, in the case of the  H.M.S Vanquisher it is 34 knots, beyond a small limit, if you overpower this model, it will LOOK like it is going faster, but all that happens is the bow wave climbs higher, the mid section of the boat dries out and the stern wave climbs higher.
This means that the model is supported at each end and not in the middle, this will cause it to be unstable rolling violently from side to side, what makes it worse is the fitting of propellers with too much pitch (usually brass ones).  These can have a paddlewheel effect on the surface of the water when one lifts out on a roll so one is working full chat when its deeper, the opposite one is not working at all, this throws the model over to the opposite side where, and so it all starts again.

So if you have a model that seems to be unstable, the first thing to look at is the props. If you have a pair of brass props, try changing them for some of the nylon 3 blade type, I know they do not reverse, but if it eases the rolling problem it means you are on the right track.

Then try changing the "buggy" type motors you have fitted, Boats need a steady torque motor, not a car type screamer.
If you were sold this type of motor by a model shop as their recommendation, (in direct contradiction to the instructions with the kit) try taking it back and letting the gentlemen know that their stupidity nearly lost you your boat, If your model has snap rolled and is now at the bottom of the lake with the deck torn off by the mast you could try words a little stronger with more Anglo Saxon in the contents.

The best type of motor for a warship gives a slow and steady push with no violent starting or accelorating and this should be turning a med. pitch prop to give a steady push, a large blade area also helps as this give a good bite on the water when you want the world to stop rushing by your porthole.

If in doubt on the motor front, try reducing the voltage to the motor first, if you drop the volts from say, 6 to 4.8 you may find that you have increased your running time and not lost any speed, do not rely on your eye, measure the speed between post with a stop watch.
Just because you do not have a bow wave climbing over the deck you will find that you are going just as fast through the water.
Last but not least, LOOK at what the model is doing, close to you, not out in the middle of the lake, see if she is biased one way, or bow or stern heavy, the best guide is when a model is running into a steady swell to give a good idea of what is  happening.

Also remember that when you wish to turn a fast ship, do not go howling along at full speed and smash the rudder over to full lock, Modern radio gear responds like that, if you try it on a real destroyer, first the rudder shaft bends, just before the stern is torn off. It very distinct you cannot miss it, and you get all sorts of difficult questions asked of you, "what are you going to do next in your new job?" etc , so ease the rudder over, and try dropping the revs a little before you turn. As the model heels  and turns, apply the revs again to drive it out of the turn.
Try it out, you might like it. It is a bit like riding a bike, you coast it into corners, and accelerate out.
Not the look mum no hands, look mum no teeth type of driving.

One last point, I know model warships look stunning on the water, lots of grace and style, but it helps if you look where you are going now and again, its not that I wish to mother you, and spoil your fun, but a destroyer going full chat, well its like a 30 knot Stanley knife, And I may be in front of you.
                                                  HAPPY SAILING.

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