Hi Anthony

You could add weight when the model is in the water by pumping water into tanks.

You could use long low tanks with built in anti slosh plates to keep the centre of gravity low down and prevent the water from moving around as you turn the model.

Paul

Hi Ashley

Electric pumping into ballast tanks works well for me I use a 12v high capacity pump in my larger models to fill and empty the tanks, these pumps can shift 40 litres a minute so they soon fill the tanks. This is a great help to me as I am now unable to lower fully ballasted boats into the water.

Paul

Hi Bob

Nice idea but the plank boat would be top heavy and therefore very unstable. likewise the free flooding hull which sounds feasible but if the water is not contained within tanks then it will allow the hull to roll in the water and could even induce capsize.

Hope the aspirins help with the headache

Paul

Hi Bob

By all means the plank idea could have a keel but then you would be back to a ballasted boat with all of the incumbent weight problems that a normal hull would have. The keel could be demountable for transport but would have to be in position prior to launching.

I hope your headache is better.

Paul

Hello Bob

Whilst I agree that a plank is a plank and whilst the plank in its original state will be stable and float very well I cant agree that when used as a base for a waterline type model that it will retain its stability as the superstructure would make the model inherently top heavy especially when maneuvering so the addition of a keel of a greater weight than that of the structure above the water line would be required.

However I do agree that a traditional hull would require more ballast than your plank idea and that the motors, batteries etc slung under the plank would be an aid to the ballast.

Perhaps you should build a demo model to prove the therory.

What match??

Paul the non football supporter

Hello Ashley

That`s very interesting!……………….The self flooding model needn`t have a hull bottom at all and then the model could be lifted straight out of the water?

Thank you….Bob

Gary. I am sure this will help. I assume the fleetscale is a Fibreglass hull ? If so perhaps a false bottom could be fibreglassed in and used as a water hold…this would use up all available space, holding even more water ballast.

The rest, concerning the plank idea. i have finished my 48×5  inch HMS Glorious, built using best homebase 3/4 inch plank and 1/8 inch hardboard in apart from looking good, it floats nicely and is very stable. i simply cut an oblong hole out of  the plank, plated it over underneath with hardboard and this is where the batteries sit. Before, with the batteries ON the plank it was very wobbly. Just shows what difference it makes on exactly where you put your ballast. Seem to be unable to post pictures from our computer on to this site to illustrate. Ashley

hi

i have had a look at your bismarck and very nice it is too

i think he could do with another 10 pounds of weight to bring him down to the middle of the water line by the looks of him i reckon he is about 40 lbs!

gary

ps

the photo is my scharnhorst at kingsbury navy day 2007

Hi there Anthony,I was very lucky in that my grandfather a soldier in the first world war collected the Ministry of Information booklets issued to the general public during World War two, and gave them to me a couple of years after the wars’ end. I read them all from cover to cover, especially the ones dealing with the battle of the River PlateI developed an enormous respect for the german big warships including the Bismarck at 50,000 tonswhich compared well to our RodNel ships at 75,000tonsBismarck had a lot of armour but a reasonable gross weight which meant that she could move pretty quickly. I’m not saying the captain could waterski, buthe could demand a fair turn of speedfor a ship that big. They were all ideally suited to the role of deep water predatorsThe british navy was hidebound and stuck in history wit the insistance on sixteen inch guns that needed a ton of cordite to send their little messages of love to the enemy ships. Amazingly, the Americans are still lumbered with one of those old battlewagonsin the Iowa, but then they were retained for their ability to bombard shore positions from a position out at sea. A quick burst from my phd in hindsight, we did a lot better in 1961 with a relatively small ship at 22000 tonsduring the Kuwait crisiswhen we launched wave after wave of scimitar aircraft loaded with 1000pound bombsagainst the Iraqi tanks. the aircraft not only acted as bombers, but with sidewinder missiles acted in the defence role. The ship, HMS Centaur also carried sea vixen aircraft armed with firestreak missiles and 2 and three inch rocket projectiles  for ground attack, from a modelling point of view, the big gun battleships make brilliant models, dont let bismarck wallow