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[Malcolmbailey]

hello, I am still a beginner!
I have made a 1/96 model of a F class ww2 destroyer with a flat bottom.
I am told it should have two bilge keels but I don’t know where they should be fixed.
Help please!
Malcolm

[Arrow5]

Flat bottom ? Might not need them, what is the cross section like ?

[nemesis]

normally where the floor( bottom) meets the side of the hull. On the curve give or take a bit. nemesis

[Malcolmbailey]

Hi
Thanks for your prompt replies.
Tha bottom of the boat is 4” wide and the radius of the curve to the vertical side is about that of a one penny piece.


Malcolm

[John W E]

Bilge keels  on a 1/96 model  T42 Destroyer


john

[Bob K]

John, you just beat me to it !

Below is picture of the bilge keels on my HMS Agincourt.  Yes, it does have a flat bottom, and near vertical sides.



The bilge keels must be contained within the "box profile" of those surfaces, so as not to protrude beyond the keel face or hull side faces.  They are designed to limit the roll of the ship, which is necessary on a long thin warship that needs to be a steady gun platform.

[Malcolmbailey]

Thank you again. Your advice Bob and John re the protrusion of the bilge keels is what I wanted to know.
I shall endeavour to fit two but they will have to be fairly narrow.
I did try to post a photo but the site would not take it and I don’t know how to reduce the size of a photo on my iPad.
All this has come about because I displayed my model at the Boat Show at Haydock Park last weekend and invited constructive comments!
All for the good.
Malcolm

[Colin Bishop]

You have put your finger on it there!
For maximum effect, bilge keels need to be quite large but in practice they are limited by the need to fit within the 'box profile' as Geoff says to avoid damage when dry docking or when alongside quays.
There were experiments carried out in pre dreadnought days to quantify the effects of bilge keels and generally the larger the better! But practical considerations limited size. As always a compromise until stabilisers came along after WW2 by which time a steady gun platform was less important.

Colin

[raflaunches]

It’s amazing the difference having bilge keels being fitted. My Dreadnought doesn’t (it should) and rocks quite heavily whilst my Invincible does and it’s so smooth in comparison. They can be a pig to fit but worth it.

[Colin Bishop]

Yes Nick, even on a model they can make a significant difference.
A good example of getting a lot for not very much effort.
I find that angle brass section is pretty good in accommodating hull lines and you can position it so that the flat bit is on the keel side and pretty invisible whilst providing a good glueing and pinning surface so that only the pins actually penetrate the hull.

Colin

[Malcolmbailey]

Thank you all,
I have decided that I can glue a shaped fillet, carved from fibreboard, to the bottom of my model. This would be 1/4 “ in the centre tapering to the sides. This will facilitate insertion of bilge keels of 3/8”, improve the lines and produce a good result.
Malcolm

[John W E]

hI YA Malcolm - if you go down to about reply about 74 on the link I am going to put on and have a close look at the hull side of the destroyer - you will see the bilge keels they are a bit obscured because of the model stand - this is the best pic I have of her as this model now resides in Wales John


http://www.modelboatmayhem.co.uk/forum/index.php/topic,3462.50.html

[Malcolmbailey]

Hello John,
Many thanks for you comments. I have had a look at your posts referred to which are extremely helpful.
The fillet I am going to add to the bottom of my model will bring it similar to that of your model and wil let me attach bilge keels within the limits referred to earlier.
I shall go through your posts more carefully later as there is much to learn from them.
Thanks
Malcolm