Boat survey help

[thepurpleplatypus]

We've just receive the purchase survey from our first ever boat. Most of the things on the list make sense but one has me a bit baffled.

 

"It would be best practice to weld the forward base plate seam externally."

 

It's just an advisory but I'm curious why this should be done? I'll probably give him a ring to ask but I thought I'd ask here as well.

 

 

cheers

Adam

 

[SUIGENERIS]

Very often builders build the boat with the base plate stood on a concrete floor. In which case they weld any joints in the base plate from above. In most cases the weld is sufficiently penetrating for there to be little cavity between the plates if viewed from below. however sometimes the penetration is less and that is more often the case where a thicker base plate has been specified.

 

Some builders have no means to lift a boat hull sufficiently to make an external weld, so the boat is despatched with a slight void existing between the plates.

 

If the surveyor thinks it needs doing, then it probably does!

 

Mick.

[David Mack]

Very often builders build the boat with the base plate stood on a concrete floor. In which case they weld any joints in the base plate from above.

And the best then turn the base plate over and weld the other side before building the rest of the boat.

[Tony Brooks]

And what about any other base plate seams? If there are any.

[MtB]

And what about any other base plate seams? If there are any.

 

Yes the wording puzzled me a bit too. It sort of implies there is more than one joint in the base plate and the others ARE welded from both sides.

 

Having said that it isn't as 'cut and dried' as first appears. I'm not an expert welder but as I understand it a perfectly good full depth weld can be achieved if done right, in which case there is no point in running a new line of weld across the underside of the baseplate. Welding upside down is very skilled anyway so may not get done that well even if you commissioned it.

 

The surveyor makes no comment on the degree of penetration of the builder's weld done from the top. This is what's important. I suspect it's fine or he would have said so, but ask him!

 

 

 

(Spelling edit. Must put my reading glasses on BEFORE pressing 'send'!)

Edited January 9, 2016 by Mike the Boilerman

[Markinaboat]

From what I understand, the hull sides rest on top of the baseplate which should always protrude further out than the hull and so provide a sacrificial edge. The welds are on the inside and/or outside. In this case it would appear that the weld is run along the inside of the boat. I do not understand the above comments as what would be the benefit of running a weld along a flat piece of metal without joins? Apologies if am missing something here but not long up!

 

As for surveyors, they will always state 'this or that' as they have to put something in. They rarely state how fantastic a hull is even if they've commented face to face. I've just had my other boat surveyed at Bullsbridge for insurance purposes (25yrs old this year) and it had been on a residential mooring with shore power for four years (apart from perhaps 3 mths away cruising). The surveyor reckoned the anodes were just 15-20% worn and he was surprised at the overall good condition of the hull given that there were other boats hooked up to power (electrolysis). This was helped by a galvanic isolator having been fitted. However, the survey report stated that the hull was in a 'serviceable' condition.

 

They can be a strange breed.

[john6767]

The welding of the baseplate on the outside is something that our surveyor commented while he was looking at he boat, as in he was pleased to see that it was fully welded, and he explained to me that, as mentioned, some builders build on the floor and don't weld that side of the base plate. He also commented that the rubbing strakes were fully welded top and bottom and that some builders only tack them on the bottom.

 

While on the subject of welding he told me about an almost new boat he surveyed that had plates tack welded together and then mastic over the joint, yikes!

[Markinaboat]

The hull side is butt welded to the baseplate. Think of it as a T upside down. Therefore, no welding is possible from underneath, just inside the hull/boat and on the outer edge.

[thepurpleplatypus]

Thanks folks. That helps clarify things.

[Alan de Enfield]

I did not read it as the weld attaching the base plate to the hull - I read it as the separate pieces forming the base plate - ie there may be several 'lengths' of 10 foot by 6 foot 6" plate that is welded to achieve the overall length of the boat.

 

The surveyor commented that the forward weld was not 'done' externally, implying that the others were.

 

Just my 2p.

[Tony Brooks]

Or that for some reason he had not inspected any others. We can't know what he actually meant so are just guessing really.

[TheBiscuits]

I did not read it as the weld attaching the base plate to the hull - I read it as the separate pieces forming the base plate - ie there may be several 'lengths' of 10 foot by 6 foot 6" plate that is welded to achieve the overall length of the boat.

 

And I thought that 12mm was getting excessive for base plates!

[Markinaboat]

I did not read it as the weld attaching the base plate to the hull - I read it as the separate pieces forming the base plate - ie there may be several 'lengths' of 10 foot by 6 foot 6" plate that is welded to achieve the overall length of the boat.

 

The surveyor commented that the forward weld was not 'done' externally, implying that the others were.

 

Just my 2p.

Good point ALAN! I wonder if it's acceptable practice to create a deep V groove to weld from the top/inside through to (almost) the bottom? Edited January 9, 2016 by Markinaboat

[WotEver]

 

And I thought that 12mm was getting excessive for base plates!

Oh no, 6" base plates are the minimum these days ? CaRT pay you for helping dredge the channel...

Good point ALAN! I wonder if it's acceptable practice to create a deep V groove to weld from the top/inside through to (almost) the bottom?

Surely that is standard practice?

[Alan de Enfield]

 

And I thought that 12mm was getting excessive for base plates!

 

I hadn't realised I had quoted a thickness, just lengths of 10' and widths of 6' 6"

 

Now you are getting me confused.

[WotEver]

 

I hadn't realised I had quoted a thickness, just lengths of 10' and widths of 6' 6"

 

Now you are getting me confused.

You hadn't, we were just teasing.

 

Your original wording was

10 foot by 6 foot 6" plate

as opposed to your revised wording above. Edited January 9, 2016 by WotEver

[Machpoint005]

>> the survey report stated that the hull was in a 'serviceable' condition.<<

 

They can be a strange breed.

 

Are they of the same breed as OFSTED inspectors, to which 'satisfactory' used to mean 'unsatisfactory'?

 

I do hope not. If the hull remains 'serviceable' for another 10 or 20 years you're laughing!

[Tony Brooks]

Thinking about the report.

 

If my surveyor wrote that I would not be happy. If the "fault" was as we seem to suspect I would hope the surveyor measured the depth of no weld penetration so that by comparing it with the plate thickness both he and the OP could asses just how serious this potential problem was.

 

I see no measurements but the OP may have them.

[Neil Smith]

As already stated best practise is to grind a V so the weld can be built up from the bottom to fill up the V and you get a solid joint with no voids.

 

Neil

[MtB]

As already stated best practise is to grind a V so the weld can be built up from the bottom to fill up the V and you get a solid joint with no voids.

 

Neil

 

 

Quite.

 

What we don't know is if the surveyor knows this, and can recognise the underside of a weld where this has been done.

[FadeToScarlet]

 

Are they of the same breed as OFSTED inspectors, to which 'satisfactory' used to mean 'unsatisfactory'?

 

It still means that to Ofsted, "satisfactory" was renamed "requires improvement" about 4 years ago.

[Machpoint005]

Yes, that's what I thought.

So does 'serviceable' imply 'only just serviceable'?

[Tony Brooks]

Yes, that's what I thought.

So does 'serviceable' imply 'only just serviceable'?

 

Hence the need for the depth of the un-welded part of the seam. If it was 8 mm in a 10 mm base plate then I would say yes. If it was 1 mm then I would say perfectly serviceable.

[alan_fincher]

I also assume the comment is about a join between bits of a baseplate made from joined sheets, and nothing to do with joining hull sides to base plate.

If there are multiple joins, and surveyor has only commented on one, I would not assume it does not apply to another one. One possibility is that when the boat was dry docked, pulled out on a trolley, or craned out, any further rearward join has ended up sitting on the chocks or trolley involved, so can't be inspected. Surveyors will usually put something in their report that says anything obscured in this way can't be inspected, so they cannot pass comment on it.

 

When we bought "Chalice" the surveyor picked up on baseplate weld being from above only, (there was only one join). His report stated how far he had been able to push a very fine blade into it at the worst point found, giving some idea of the degree of penetration of the single weld. It wasn't that bad, (3mm, I think?), but we elected to have it done anyway. However given a lack of clearance for the welder to get underneath the boat to do it, I often wondered if doing so was just a token exercise, and if that extra welding had truly filled any possible weaknesses. If nothing else it meant one thing a surveyor couldn't comment on when we finally sold it.

[MtB]

I also assume the comment is about a join between bits of a baseplate made from joined sheets, and nothing to do with joining hull sides to base plate.

 

If there are multiple joins, and surveyor has only commented on one, I would not assume it does not apply to another one. One possibility is that when the boat was dry docked, pulled out on a trolley, or craned out, any further rearward join has ended up sitting on the chocks or trolley involved, so can't be inspected. Surveyors will usually put something in their report that says anything obscured in this way can't be inspected, so they cannot pass comment on it.

 

When we bought "Chalice" the surveyor picked up on baseplate weld being from above only, (there was only one join). His report stated how far he had been able to push a very fine blade into it at the worst point found, giving some idea of the degree of penetration of the single weld. It wasn't that bad, (3mm, I think?), but we elected to have it done anyway. However given a lack of clearance for the welder to get underneath the boat to do it, I often wondered if doing so was just a token exercise, and if that extra welding had truly filled any possible weaknesses. If nothing else it meant one thing a surveyor couldn't comment on when we finally sold it.

 

 

 

I'm not so sure about that. I bet if you gave the same fault-ridden boat to three different surveyors you'd get three different lists of problems back. As an impoverished Decca apprentice I was in the habit of buying scrap cars out of front gardens, MOTing them and flogging them to make some decent money. If one failed an MOT taking it to a different MOT station instead of fixing the supposed faults often resulted in a cheaper pass than 'fixing' the supposed faults!

 

Good subject for a WW magazine article actually. Find a crap boat, book endless surveys and write up the varying results.