Hull thickness question

[The dog lady]

Looked at a boat last week at a brokerage and decided to go for survey. Only five years old and looks in good condition. In the broker's info it gave hull bottom thickness as 10mm, surveyor's report says 8mm everywhere but down to 7.7mm in places. Also original invoice from boat builder says 8mm but fitter's spec says 10mm. No-one seems to know what's happened. Is an 8mm bottom on newish boat unusual? Is it a potential problem when selling on? Any advice please?

[mrsmelly]

7 minutes ago, The dog lady said:

Looked at a boat last week at a brokerage and decided to go for survey. Only five years old and looks in good condition. In the broker's info it gave hull bottom thickness as 10mm, surveyor's report says 8mm everywhere but down to 7.7mm in places. Also original invoice from boat builder says 8mm but fitter's spec says 10mm. No-one seems to know what's happened. Is an 8mm bottom on newish boat unusual? Is it a potential problem when selling on? Any advice please?

8mm is no problem whatsoever. I had a colecraft with a 6 mm bottom built in 1981 and I know it still hasnt had a bottom plate repair. This will be a case of The estate agent just assuming things. I reckon the baseplate will be of 8 mm and is therefore in good nick. The cost in production will have been slightly lower but if you like the boat dont be put off.

[Alan de Enfield]

7 minutes ago, The dog lady said:

Is an 8mm bottom on newish boat unusual? Is it a potential problem when selling on? Any advice please?

It would be 'unusual'. Most modern boats (say the last 10 years) would tend to have a 10mm bottom as standard.

I suppose one of the 'economy builders' could have used thinner steel to save a few pounds.

I'd suggest that the surveyors figures (assuming he actually measured it) would be the correct ones.

 

Who was the builder ?

 

If there are two 'identical' boats, one with an 8mm and one with a 10mm bottom I'd suggest that the 10mm one will sell first.

Everyone will want the best specification for their money.

[The dog lady]

Alan..I think you are right about the 'economy' builders - small outfit, two men and their dog . I was with surveyor when he took measurements. It's annoying as I wouldn't have paid out for a survey if the spec details had said it was 8mm. The owner had signed off the sales particulars. The boat is still on broker's website despite now knowing about the discrepancy. Misleading to say the least.

[TheBiscuits]

21 minutes ago, The dog lady said:

original invoice from boat builder says 8mm but fitter's spec says 10mm.

I'd believe the boat builder and the surveyor ...

[TheBiscuits]

... and my bottom was quarter inch plate (6.25mm) 30 odd years ago and still keeps the water out despite me crashing over lots of rocks and shopping trolleys

 

Don't worry about it!

 

[mrsmelly]

Pat Buckle built plenty of thinner boats as did many others. there are thousands of earlier boats out there with less than 8 mill bottoms all perfectly serviceable. Its only a recent, last few years that most do 10/6/4. I have owned 15/6/5 my last boat was 12/8/4 and the present one is 10/6/4. Condition is vastly more important than thickness.

1 minute ago, TheBiscuits said:

... and my bottom was quarter inch plate (6.25mm) 30 odd years ago and still keeps the water out despite me crashing over lots of rocks and shopping trolleys

 

Don't worry about it!

 

Precisely.

[Alan de Enfield]

10 minutes ago, The dog lady said:

Alan..I think you are right about the 'economy' builders - small outfit, two men and their dog . I was with surveyor when he took measurements. It's annoying as I wouldn't have paid out for a survey if the spec details had said it was 8mm. The owner had signed off the sales particulars. The boat is still on broker's website despite now knowing about the discrepancy. Misleading to say the least.

As had been said - there is no problem until the measurement reaches 'zero', but you asked the question about re-sale.

 

Do you not see this as your 'forever boat' ?
Is it your 1st boat ?

 

If you are planning now to re-sell it then maybe it is not the best boat for you - but yes - a thinner bottom would put-off potential buyers as it appears it may be doing to you.

[bizzard]

Fresh air is nasty, it rust things. I'd avoid keep docking the boat every five minutes to do blacking. Do it once with new anodes and then not again until the anodes are almost depleted. Keep docking lets the fresh air get to the baseplate to encourage rust. Leave lids off jars of jam and let the fresh air in and it goes bad.  We age because of the fresh air, its best to live in a vacuum.

[rusty69]

6 minutes ago, bizzard said:

its best to live in a vacuum.

We're all gonna Dyson.

 

 

 

 

 

 

 

..............It sucks!

Edited April 3, 2019 by rusty69

[Sea Dog]

8 minutes ago, rusty69 said:

We're all gonna Dyson.

..............It sucks!

Yeah but... At least with a Dyson you don't have to live with an old bag!

[Boater Sam]

Its fairly common to find that the uxter plate under the fuel tank at the stern is not 10mm plate, Its the way the uxter plate is cut from the rear of the base plate, it leaves this  plate short so many builders chuck in a piece of odd 8mm plate.

Its like dress making, the offcuts of steel are used elsewhere to save costs, if its 8mm I would not be at all concerned.

It will take a long long time to wear 8mm down to 4mm, it could even be that the 8mm plate is a better steel than the 10mm.

[ditchcrawler]

3 minutes ago, Boater Sam said:

Its fairly common to find that the uxter plate under the fuel tank at the stern is not 10mm plate, Its the way the uxter plate is cut from the rear of the base plate, it leaves this  plate short so many builders chuck in a piece of odd 8mm plate.

Its like dress making, the offcuts of steel are used elsewhere to save costs, if its 8mm I would not be at all concerned.

It will take a long long time to wear 8mm down to 4mm, it could even be that the 8mm plate is a better steel than the 10mm.

Some people say its better to weld steel of a similar thickness together, I have no idea if that is true, Steve use to glue 8mm to 15mm and even 20 mm 

[mrsmelly]

8 minutes ago, ditchcrawler said:

Some people say its better to weld steel of a similar thickness together, I have no idea if that is true, Steve use to glue 8mm to 15mm and even 20 mm 

Baseplate on my Udson was 15 with hull sides of 6. No problems whatsoever. I still reckon 8 mil will be absolutely fine. the 15 mil bottom simply meant bugger all ballast with just engineering bricks for ballast. It will live no longer.

[Bee]

8mm is plenty thick enough for any boat anywhere, The important thing is to keep it that way, docking, painting (everywhere, bottom as well)  is the thing to do.

[LadyG]

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