Keel shoes or not

[catmandoo]

My catamaran is fitted with SS shoes on each stub keel to avoid damage incurred when hitting old cars and prams as it went down the French canals .

I am now wondering if this is not such a good idea now for the open sea .

I keep thinking of pitching and the pendulum effect despite having flopper stoppers .

If I took the shoes off would I reduce the frequency of pitching in rough seas or increase it bearing in mind that pitching occurs diagonally as well as fore and aft ???

It would appear that it depends upon the effect of the masses at the end of the keels on the CG in relation to its distance from the axis of rotation which I presume is the centre of buoyancy

In view of the mass of these in relation to the overall mass of the boat and water displaced I assume that it is possibly so insignificant that I would probably not notice any change ???

 

[boatbuilder]

I doubt that you would even notice.

 

[oldsaltoz]

G'day Catmandoo,

Quote
My catamaran is fitted with SS shoes on each stub keel to avoid damage incurred when hitting old cars and prams as it went down the French canals .

I am now wondering if this is not such a good idea now for the open sea .
End Quote.

They will continue to provide protection when drying out or grounding.

Quote:
I keep thinking of pitching and the pendulum effect despite having flopper stoppers .
End Quote.

This must be only cat with flopper stoppers I ever heard of, are your keels so close together that flopper stoppers do anything at all to reduce roll or pitch?


Quote:
If I took the shoes off would I reduce the frequency of pitching in rough seas?

In view of the mass of these in relation to the overall mass of the boat and water displaced I assume that it is possibly so insignificant that I would probably not notice any change ???
End Quote.

You have answered your own question, little or no change.

Avagoodweekend......

 

[catmandoo]

[ QUOTE ]
G'day Catmandoo,



This must be only cat with flopper stoppers I ever heard of, are your keels so close together that flopper stoppers do anything at all to reduce roll or pitch?


[ QUOTE ]


[/ QUOTE ]

flopper stoppers are at canoe shaped stern of each hull and are hoerizontal . They work like an aerofoil at best when at speed and provide reverse lift . Seem to be quite effective. Each hull is about 4 metres apart