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25mm Bottom Plates

I am researching travelling to the UK in a few months time and ordering a wide beamed boat. In looking at design specs it would seem that it would be best (to get away from excessive ballast and to keep height in the boat) to get a 25mm base plate as part of the structure i.e. 25.6.5 instead of the more usual 10.6.5. My question is - is this feasible or normal and what does it do to the price of the plates against the cost of ballast?.

Asked by: PAUL BROWNETT  | 6.15am, Thursday 15 July

WW says:

25mm bottom plates are used occasionally and, as usual, there are advantages and disadvantages.
On the plus side, the need for ballast is reduced or eliminated which means that you can increase the headroom, although it would be better to give up some of the space saved for better ventilation of the bilges.
A thicker bottom plate will also take much longer to corrode to a point where patching or welding is needed.
On the minus side, the extra weight is evenly distributed so you may still have to add some ballast to compensate for a lop-sided layout.
There is also a school of thought that says that it is not good practice to weld sheets of steel of such varying thicknesses together. Your builder may be able to advise or you could plough your way through the relevant British Standards.
Looking at the financial implications, it is difficult to advise as the price of steel fluctuates. The cost of different types of ballast and the charge for laying it also varies from one builder to another. However, I suspect that the thicker base plate solution is probably the most expensive initially but may pay dividends in the long run.

Graham Booth  | 10.22AM, Friday 16 July

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