Pitting on hull requiring spot welding. Survey

[dan01eb]

Hi, I'm in the process of buying my first narrowboat to live aboard. It was surveyed today and I've just received a quick update from the surveyor saying there's some pitting on the hull that needs spot welding. I'll receive the full survey report in the next couple of days. The boat is 16 years old and is for sale for just over 50k. Is pitting that requires spot welding a serious problem? Thanks in advance.

[Tracy D'arth]

How much and how deep?  Where?

[dan01eb]

3 minutes ago, Tracy D'arth said:

How much and how deep?  Where?

I'm not sure yet, I'll have to wait for the full survey report in the next couple of days. I just saw pitting and welding and feared the worst.

[system 4-50]

Are you certain it is 16 years old?

[dan01eb]

5 minutes ago, system 4-50 said:

Are you certain it is 16 years old?

Almost certain. Why do you ask? Would pitting and needing welding not usually be expected on a 16 year old boat?

[matty40s]

It is fairly common as opposed to unheard of nowadays to have pitting needing welding on narrowboats not much more than 10 years old. Sometimes, there are a couple of deep pits, sometimes there are many.  Most surveyors are now insisting on side low profile anodes being welded on, even though this only really protects the 4 feet round that anode. There are also surveyors insisting that almost all boats they survey need pad welding (they also know a yard where their brother does pad welding)

Many factors contribute to this, steel quality, the amount of electrical kit people now insist on having on a boat, both 240 and 12/24v, the amount of boats in marinas where all those new boats share circuits and water, new boaters thinking they will get 5 years before blacking.

So, if it is just a couple of pits that need spot welding, then no worries, its a fairly simple fix, especially if you can get it done before the boat gets refloated.

however, if its more than just a couple of pits....we recently had a boat that the surveyor said 50 plus each side, and refused, then no, the boat has a serious steel , electrical, maintenance historical issue that welding a few pits will not solve. 

you need to drill down with your surveyor - they will not like it as they are very risk averse - or get a second opinion swiftly.

[Alan de Enfield]

44 minutes ago, dan01eb said:

Almost certain. Why do you ask? Would pitting and needing welding not usually be expected on a 16 year old boat?

 

It depends on the 'water conditions' and 'electrical conditions' the boat has been moored in.

 

In 'good' conditions it certainly shouldn't need any welding at that age.

In the 'worst' conditions it has been known for a boat to get 6mm deep pits in 18 months.

 

You are probably in the 'middle'but until you find out the depth and extent of the pitting its all guess work.

[Paul C]

 

Errrrrr, its not "spot welding", that's the totally wrong term to use. But I can see why someone might describe it as such.

[matty40s]

19 minutes ago, Paul C said:

 

Errrrrr, its not "spot welding", that's the totally wrong term to use. But I can see why someone might describe it as such.

That comes from Professional Boat Surveyors to the highest of their standards.🙃

[Stroudwater1]

It’s quite likely to be difficult to assess the amount of pits p he needing pit welding without grit blasting back to bare steel. Then pit weld what’s needed then epoxy which will give better protection for the future. 
 

Friends boat went from needing overplating on the survey to a few pits welded after grit blasting. It’s not that exact a science it seems. 
 

 

[David Schweizer]

12 hours ago, matty40s said:

That comes from Professional Boat Surveyors to the highest of their standards.🙃

 

The  Surveyor's observations clearly demonstrate that he does not have an engineering background. PaulC is correct, Spot welding is a process used to weld sheet material between two electriodes.

[alan_fincher]

14 hours ago, dan01eb said:

Almost certain. Why do you ask? Would pitting and needing welding not usually be expected on a 16 year old boat?

 

To me the biggest issue is the sale price of just over £50K, (though I realise you may already have negotiated a lower figure).

 

Obviously how many pits and how deep will be very important, but to me any significant number and depth then I would not like to be paying that kind of price

[Higgs]

One firm I enquired at quoted £10.00 a spot weld, or £60.00 an hour. I only spoke to one firm, so it's not comprehensive. So, in valuing the boat being bought, any welding requirements should be used in negotiation on the price. 

 

 

Edited October 24, 2023 by Higgs

[Paul C]

1 hour ago, Higgs said:

One firm I enquired at quoted £10.00 a spot weld, or £60.00 an hour. I only spoke to one firm, so it's not comprehensive. So, in valuing the boat being bought, any welding requirements should be used in negotiation on the price. 

 

 

Once the welder is set up, it takes about 2 secs per ‘pit’. If you get the settings right, you don’t even need to grind anything down afterwards either

[Tracy D'arth]

See what Debdale quote for welding by the hour, its the lift out that costs. £60 an hour plus wire/rods is not unreasonable, +VAT?

[blackrose]

3 hours ago, Higgs said:

One firm I enquired at quoted £10.00 a spot weld, 

 

..per welded pit might be a better phrase.

 

18 hours ago, matty40s said:

Many factors contribute to this, steel quality, the amount of electrical kit people now insist on having on a boat, both 240 and 12/24v, the amount of boats in marinas where all those new boats share circuits and water, 

 

I think there are a few popular myths mixed in there. If a boat has correct 12v wiring & circuits and the mains earth path is properly isolated then the amount of electronic equipment on board is irrelevant as far as pitting is concerned. There are commercial vessels all over the world with far more electronic equipment onboard than the average canal boat. I think this myth is more to do with a traditionalist narrowboat mindset than anything else. The idea that anything on a boat which makes life easier is going to result in negative consequences.

 

Of course, if the electrical systems have not been properly installed and isolated then yes that will result is premature hull corrosion and pitting but that's another matter.

 

Similarly the idea that modern steel is of inferior quality than old steel is another popular myth on the canals, again stemming from the traditional narrowboat mindset that thinks everything old is better. Modern steel is in fact of better quality than it was in the past due to tighter steel specifications. 

 

I suspect the real reason we see more cases of pitting these days is simply because there are far more boats around. Also as you alluded to in your post, there are far more neglected boats around now as the amount of boats requiring attention has outpaced the amount of yards where they can be taken out the water. So the laws of demand & supply dictate that taking one's boat out the water has become relatively expensive and so some people are less inclined to do it when they should.

Edited October 24, 2023 by blackrose

[David Mack]

Also perhaps changing attitudes by both boat owners and surveyors? At one time nobody would have got too worked up about a bit of rusting on a 6mm steel plate - it's a lot thicker than car bodies after all. But these days surveyors are more inclined to report every pit and owners and buyers consequently get more worried, and hence more pit welding and overplating is done (whether it is really needed or not).

[MrsM]

7 hours ago, blackrose said:

 

..per welded pit might be a better phrase.

 

 

I think there are a few popular myths mixed in there. If a boat has correct 12v wiring & circuits and the mains earth path is properly isolated then the amount of electronic equipment on board is irrelevant as far as pitting is concerned. There are commercial vessels all over the world with far more electronic equipment onboard than the average canal boat. I think this myth is more to do with a traditionalist narrowboat mindset than anything else. The idea that anything on a boat which makes life easier is going to result in negative consequences.

 

Of course, if the electrical systems have not been properly installed and isolated then yes that will result is premature hull corrosion and pitting but that's another matter.

 

Similarly the idea that modern steel is of inferior quality than old steel is another popular myth on the canals, again stemming from the traditional narrowboat mindset that thinks everything old is better. Modern steel is in fact of better quality than it was in the past due to tighter steel specifications. 

 

I suspect the real reason we see more cases of pitting these days is simply because there are far more boats around. Also as you alluded to in your post, there are far more neglected boats around now as the amount of boats requiring attention has outpaced the amount of yards where they can be taken out the water. So the laws of demand & supply dictate that taking one's boat out the water has become relatively expensive and so some people are less inclined to do it when they should.

Really interested to read your response. I know absolutely nothing about this but my husband is a steel boat design engineer (of naval vessels) and that aligns with his view. 

[john.k]

Ive spent days filling a 'few pits'...when the paper thin steel blows thru ,and you have to try and fill a ever bigger hole with weld.

[Paul C]

5 hours ago, john.k said:

Ive spent days filling a 'few pits'...when the paper thin steel blows thru ,and you have to try and fill a ever bigger hole with weld.

What kind of welder?

[Stroudwater1]

18 hours ago, alan_fincher said:

 

To me the biggest issue is the sale price of just over £50K, (though I realise you may already have negotiated a lower figure).

 

Obviously how many pits and how deep will be very important, but to me any significant number and depth then I would not like to be paying that kind of price

£50k for a 16 year old boat if now treated with epoxy after pit welding and going forward comes out to be inspected from time to time seems a reasonable price- it depends on length overall condition and layout engine etc of course. 
We are talking about one built in around 2007. Look at Rugbys website and there’s several unexceptional boats of that age in the £60k area. 
For sure it’s  a negotiable price with the pits. 
 

14 hours ago, Tracy D'arth said:

See what Debdale quote for welding by the hour, its the lift out that costs. £60 an hour plus wire/rods is not unreasonable, +VAT?

Debdale seems a great suggestion depending on the quote. 

[dan01eb]

2 hours ago, Stroudwater1 said:

£50k for a 16 year old boat if now treated with epoxy after pit welding and going forward comes out to be inspected from time to time seems a reasonable price- it depends on length overall condition and layout engine etc of course. 
We are talking about one built in around 2007. Look at Rugbys website and there’s several unexceptional boats of that age in the £60k area. 
For sure it’s  a negotiable price with the pits. 

She's 57ft, 2007 Mike Christian with Beta 38 engine. Well equipped. Paint and interior in reasonable to good condition. Will hopefully get the full survey report later today to find out the amount and depth of the pitting.

Edited October 25, 2023 by dan01eb

[Stroudwater1]

5 minutes ago, dan01eb said:

She's 57ft, 2007 Mike Christian with Beta 38 engine. Paint and interior in reasonable to good condition. Nice spacious layout and well equipped for live aboard. Stove, good batteries and washing machine etc. I've viewed approx 15 boats and this is the one I liked the most. Will hopefully get the full survey report later today to find out the amount and depth of the pitting. The brokerage/marina say to wait for the full report but they think the pitting is minor and would be able to do any necessary welding and the blacking next week.

Sounds good 👍

If they can do epoxy then it’s well worth asking to have that done. Failing that save up and have at Debdale in 2 or three years time. 

[ditchcrawler]

10 hours ago, Paul C said:

What kind of welder?

A clumsy one  😁 

[dan01eb]

The survey report has arrived. There aren't any recommendations but quite a few advises. Some of the results are attached. Any input would be appreciated. Thanks

Edited October 25, 2023 by dan01eb