- Thread starter dutchman
- Start date
rusty69bus
moving to the goldcoast
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- 2,704
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- limbo
drill a hole and measure with a depth gauge?
tap with a hammer and listen to the tone?
tap with a hammer and listen to the tone?
Drains
Yeah, nah.
- Messages
- 7,721
- Location
- Sefton, South Island, NZ
Ultrasonic gauge is the thing dutchman. As you're in the Netherlands, there is bound to be one within about 100m of you. Lots of boats = lots of surveyors. Every surveyor will have one. Just phone up your local chap and ask how much to do a hull thickness survey on your boat. Is it a survey you need or do you just want to find out the original plating thickness?
This looks handy...
This looks handy...
............i'm not allowed to use it 
dutchman
t(r)igger happy
- Messages
- 470
I like your suggestion of measuring and calculating the difference Peter, but I am afraid it is not going to work with me old measuring ribbon, given all the crooked bends and heaps of paint on these older ships 
Probably the best option, thanks Si.
I’ve read that the hull of these size boats are usually 3 to 4 mm thick when new, but after 40 years in the water, who knows… can be anything between 0,1 and 3,9999 mm
As an experienced boat owner and builder, do you know of any spots that need to be inspected extra carefully?
Probably the best option, thanks Si.
I’ve read that the hull of these size boats are usually 3 to 4 mm thick when new, but after 40 years in the water, who knows… can be anything between 0,1 and 3,9999 mm
As an experienced boat owner and builder, do you know of any spots that need to be inspected extra carefully?
Drains
Yeah, nah.
- Messages
- 7,721
- Location
- Sefton, South Island, NZ
I like your suggestion of measuring and calculating the difference Peter, but I am afraid it is not going to work with me old measuring ribbon, given all the crooked bends and heaps of paint on these older ships
Probably the best option, thanks Si.
I’ve read that the hull of these size boats are usually 3 to 4 mm thick when new, but after 40 years in the water, who knows… can be anything between 0,1 and 3,9999 mm
As an experienced boat owner and builder, do you know of any spots that need to be inspected extra carefully?
The usual place of corrosion is around the waterline. If you're going to get large patches of thinner steel, that's the place.
Fully immersed steel shouldn't rot much. Steel well above the waterline should be reasonable too, even with seawater, so long as it's well painted. The other places to check are down in the hull, where water/moisture retention around ribs/ bulkheads has caused corrosion. Also anywhere around lead/acid battery storage, hull fittings, skin fittings, any stainless fittings onto mild steel. A visual check will usually tell you if you have to investigate further - rust streaks, bubbling paint.
You may be able to hire an ultrasonic measure.
What kind of boat is it? Got a pic?
dutchman
t(r)igger happy
- Messages
- 470
Solid instructions there Si, I should do fine knowing that. 
The boat is a 25ft sailboat that’s being sold for silly money. Thought I’d fix her up, sail it for a few years and hopefully get my money back when I sell it.
Everybody keeps telling me to buy a polyester boat and I’ve inspected a couple of them but I don’t know…. I think I will be happier in a sailing tank when there’s proper wind and waves.
I don’t have any pic’s of the actual boat, but it looks like this:
The boat is a 25ft sailboat that’s being sold for silly money. Thought I’d fix her up, sail it for a few years and hopefully get my money back when I sell it.
Everybody keeps telling me to buy a polyester boat and I’ve inspected a couple of them but I don’t know…. I think I will be happier in a sailing tank when there’s proper wind and waves.
I don’t have any pic’s of the actual boat, but it looks like this:
Drains
Yeah, nah.
- Messages
- 7,721
- Location
- Sefton, South Island, NZ
In general terms 25ft is thought about as small as you get for a steel boat. You'll never find one like that in the UK, but plenty in Holland, I bet. You get problems with polyester (fibreglass) boats if they're old and not been regularly dried out - osmosis. A steel boat will be a bit noisier.
Just beware buying a boat without a survey. Some lads I know bought a "cheap" fibreglass boat, unsurveyed, that almost sank when they first put it in the water as the keel wasn't properly attached to the hull. They spent far too long sorting it out and missed most of the season. Bloody awful sailors they were too!
Mind you, it wouldn't put me off for an obvious bargain.
Just beware buying a boat without a survey. Some lads I know bought a "cheap" fibreglass boat, unsurveyed, that almost sank when they first put it in the water as the keel wasn't properly attached to the hull. They spent far too long sorting it out and missed most of the season. Bloody awful sailors they were too!
Mind you, it wouldn't put me off for an obvious bargain.
dutchman
t(r)igger happy
- Messages
- 470
So far all the GRP buckets I inspected were complete rubbish, mainly due to osmosis. Btw, what do you mean with a survey, an expert inspection/survey?
I don't trust those so called experts... Just like doctors, lawyers, bankers, politicians, etc I don't trust any of them anymore.
The 25 footer could be a bit small indeed. In Holland there is a rule of thumb that if you want a steel sailing boat that handles well, you should buy a 30ft + length. This 25 footer has a very nice yardstick rating though, so therefore I am tempted...
However, this could be nice too
http://www.botentekoop.nl/zeiljacht...t-staal-van-der-Stadt-Cumulant-1971.html?r=18
Lot of work though
I don't trust those so called experts... Just like doctors, lawyers, bankers, politicians, etc I don't trust any of them anymore.
The 25 footer could be a bit small indeed. In Holland there is a rule of thumb that if you want a steel sailing boat that handles well, you should buy a 30ft + length. This 25 footer has a very nice yardstick rating though, so therefore I am tempted...
However, this could be nice too
http://www.botentekoop.nl/zeiljacht...t-staal-van-der-Stadt-Cumulant-1971.html?r=18Lot of work though
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