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[boatmadman]

Hi,

It has been a point of curiosity to me for a while, as I read the threads on here, specifically those related to the bigger, heavier models, it occurred to me - does anyone use water ballast and if so what do you think of it and how have you done it.

The principals are easy, just how best to apply them.

My thoughts are that it will make the model easier to handle out of the water - a real issue for GOGS and big boats.

Ian

[Bartapuss]

I have done this with my only steam powered model, M T Moorcock, I employed double bottom tanks as per full size practice to carry distilled water for the steam plant also made the model very stable as the weight is as low as you can get it. Used a revesable 12volt pump to fill and drain the tank at its lowest point.

[Martin (Admin)]

In a very minor application, that plastic tug I converted to real 2 channel radio had a water ballast tank. a very good idea I thought!
http://www.modelboatmayhem.co.uk/My_models/31%20Dickie.htm

[bogstandard]

I have a large (4ft) clyde puffer, I built in integral ballast tanks during the build. There are holes in the bottom of the hull and the boat is put into the water and the two 12volt 18ah running batteries are put in the hull. Then I open two valves and the boat gently sinks as the air is displaced with water entering from the holes in the hull. The tanks have perspex tops so I can see when they are nearly full, then as the boat reaches waterline I just close the taps and sail. Emptying is just a reversal, take the batteries out, open the taps and the natural buoyancy empties the tanks, then for the last bit I just lift the boat onto the bank and the rest of the water drains out. One boat over 30lbs lighter.

[Shipmate60]

I have seen several large models with free flooding tanks.
Not so many with Water Ballast tanks.
With WB tanks you obviously need a good fit and a watertight seal, but free flooding usually involves a false bottom and vent pipe.

Bob

[Martin (Admin)]

Hi bogstandard,
I have a slight interest in Puffers and ballast.... I'd be interested in in seeing a photo or two if possible.

Martin

[bogstandard]

I will try and get it out of deep storage and take some piccies for you. What do you need, details of the whole ship or just the ballast system?
It hasn't sailed for the last couple of years and most probably never will again, having lost most of the use of one arm it is difficult enough getting a small boat to the water, never mind something this size.

[Martin (Admin)]

Just the water ballast set up please....

[Seaspray]

I looked at water ballast and decided that the area needed for water was too much.

Decided on lead as it was heaver and would use less space.

But there are some nice setups out there using water and it helps in carrying a lighter boat to the water.

Next time maybe.

[Turbulent]

I used water as trimming ballast on my T Class, worked really well.

[bogstandard]

Hi Martin,
Here are a few pics of my puffer 'Clochlight'
The internal bulkheads are made of glass fibre, go to your local manufacturing estate and find one that does glass moulding and ask them if you can root in their scrap bins. You can get all sizes of ready moulded glass offcuts and rejects, ready to cut to shape and glass in your hull, saves a fortune for bulkheads etc.
The prop shaft actually runs through the rear tank, so preplanning has to be carried out.
All the gubbins in the last pic are an air pump and a sound board linked to the air pump that blows the generated smoke up the funnel and gives perfect syncronisation between the puff and hiss of the steam engine all synced to the motor speed.

John

[Martin (Admin)]

Excellent!

I take it the puffing unit is the red thing and motor under the rudder chains, what smoke unit do you use?

'Thanks for sharing'...
Martin.

[bogstandard]

I think the smoke unit is a tomahawk, I used to use disco smoke fluid in it, scented with a couple of drops of green apple, drove the women wild.
If anyone is interested in this model, drop round with £200 and you can take it away complete with six channel radio.
It needs a good clean and a bit of repair (just sticking things back on). It sails great and is a show stopper when in the water because of its size, everything gets out of your way, no arguments.
As I said in a previous reply, I can't handle it now because of a duff arm.

John

[Ghost in the shell]

real chain action steering, very slick :)

[bogstandard]

Works a dream, but you must be able to make the pulleys to the correct shape to prevent the chain from twisting, otherwise you are in trouble. It is so positive you need a bit of a buffer in there just in case the rudder gets knocked, I did it with the two small springs connecting the chain to the servo arm.

[boatmadman]

can you give us a pic of the pully profile please?
thanks

Ian

[bogstandard]

Hi Ian,
Here is a simple sketch of the chain pulley.
You must keep the chain totally untwisted when putting it on the boat otherwise it defeats the object of this type of pulley.
That is a quarter scale servo in the picture and the rudder is about 6" high, but it can be scaled down to any size chain.
The pulley diameter can be any size you want, as long as the chain will sit in the grooves nice and snug.

[boatmadman]

Thanks for that John, next question, where did you get the springs from?

Ian

[bogstandard]

Ian,
Just standard tension springs cut down to whatever size is required.

John

[helmsman]

Hi John
Very interesting. A couple of really good tips there. I was wondering how to do the steering on my puffer, and now you have taken all the fun out of trying to work it out.
                                              Thank you
                                                       Terry

[bogstandard]

Hi Terry,
Glad you enjoyed the tips, if you look at the picture of my puffer, just behind the rear porthole on the engineroom casement you will see a dummy chain going up to the wheelhouse, here is a sketch of the layout.

John