Can anyone suggest how to weigh a narrowboat ?

[NB Esk]

There's a lot more to it than the weight of the boat. An 80 ton crane at full stretch doesn't lift 80 tons. You'll need to let them know how far they will have to reach as well

 

Richard

Richard, I think it was post 6 I said about having crane reps around before I started the build, cheers anyway.

[DHutch]

There's a lot more to it than the weight of the boat. An 80 ton crane at full stretch doesn't lift 80 tons. You'll need to let them know how far they will have to reach as well

But you still need to know the weight!

 

I too would be surprised if it where over 15 ton, but if you that's the tipping point (no pun intended) for the reach I can see you concern and there's not a lot I can suggest beyond what's above.

 

With kitcars people buy a couple of pairs of bathroom scales and do it that way, but its not really going to scale for a narrowboat. I like the bottle jack with a pressure gauge idea, and see no reason why with care for something as long as a narrowboat it wouldnt be suitable accurate to use a single jack, with a beam at the other end, and then weight the other end in the same way. You could even do some sums on the expected error. But would reiterate the point about needing to know the area of said jacks ram, including if its a two stage ram or not, etc.

 

 

Daniel

[BEngo]

OK,

 

I'm 60 ft, vintage engine , 2'6 draft most of the way and 19T all up.

 

The question is not pure mass but mass at reach. A 45 T crane will lift Jarrah, but only close to the riggers. With a slightly larger crane you could lift, jib out to the safe limit, lower, move crane. Repeat until bored.

 

How close is the boat to where it needs to end up, how good is the crane standing between the two places?

 

N

[RLWP]

Richard, I think it was post 6 I said about having crane reps around before I started the build, cheers anyway.

 

Sorry, I missed that

 

Richard

[Guest]

I'm struggling to believe that a good crane company won't come out in advance if the site is in anyway unusual to asses it and also estimate the weight of the boat in order to correctly asses which of their cranes they need to send - OK you may end up paying for some (??lot's of) capacity if they grossly overestimate the weight of the boat but surely this is better than them getting to the site and finding the crane they have sent (based on the customers estimate) is inadequate for the job... surely you will be out of pocket then too because they will just say 'well you gave us the weight"

 

 

 

capacity not latency dumbo spell checker.....

Edited September 8, 2013 by The Dog House

[Ex- Member]

OK,

 

I'm 60 ft, vintage engine , 2'6 draft most of the way and 19T all up.

 

The question is not pure mass but mass at reach. A 45 T crane will lift Jarrah, but only close to the riggers. With a slightly larger crane you could lift, jib out to the safe limit, lower, move crane. Repeat until bored.

 

How close is the boat to where it needs to end up, how good is the crane standing between the two places?

 

N

 

You also need to assess ground structure and height as in avoiding overhead wires. We were also required to take out additional insurance, but we managed to get this wavered as out boat insurance gave relevant coverage.

 

Faffing about the weight of the boat is a waste of time, a ball park high estimate will suffice. Always assess the higher possible level, when you order this type of equipment you should allow at least 20% leeway anyway.

 

Just get an assessor to come out, there's many other factors to crane hire as well as to supplying a slinger/banksman and preparing risk assessments.

[NB Esk]

I'm struggling to believe that a good crane company won't come out in advance if the site is in anyway unusual to asses it and also estimate the weight of the boat in order to correctly asses which of their cranes they need to send - OK you may end up paying for some (??lot's of) capacity if they grossly overestimate the weight of the boat but surely this is better than them getting to the site and finding the crane they have sent (based on the customers estimate) is inadequate for the job... surely you will be out of pocket then too because they will just say 'well you gave us the weight"

 

 

 

capacity not latency dumbo spell checker.....

Yes, but that's why I was trying to get a reasonably accurate figure. I'm thinking the difference between one size of crane & the next, is likely to be a great deal of money. And me being a Yorkshireman........

 

Sorry, I missed that

 

Richard

Hey, no worries.....

 

You also need to assess ground structure and height as in avoiding overhead wires. We were also required to take out additional insurance, but we managed to get this wavered as out boat insurance gave relevant coverage.

 

Faffing about the weight of the boat is a waste of time, a ball park high estimate will suffice. Always assess the higher possible level, when you order this type of equipment you should allow at least 20% leeway anyway.

 

Just get an assessor to come out, there's many other factors to crane hire as well as to supplying a slinger/banksman and preparing risk assessments.

You know what? you're probably right. I can already see this being one of the worst, most stressful days of my life. There is a phone line that'll need to come down but the good thing is the hard standing, it's concrete over bedrock.

[Graham Davis]

OK, you're a tight Yorkie (;-}) but there is a lot more to take into account than just the weight of the boat. As said you have to consider the reach required, plus access, ground conditions, overhead wires, underground services, et al.

If cost is so important, and you do need a bigger, more expensive crane, is there anyone locally who also needs a lift. at least that way you could half the bill for a slightly bigger crane.

[Batavia]

If you look at the various crane spec details from this link, you will get an idea about the criticality of your 15 tonne cut-off figure.

 

http://www.ainscough.co.uk/cranes/

 

The figures are based on "perfect" set-up conditions, though!

 

Chris G

[Guest]

Yes, but that's why I was trying to get a reasonably accurate figure. I'm thinking the difference between one size of crane & the next, is likely to be a great deal of money. And me being a Yorkshireman........

 

But my point is if they estimate it and send inadequate kit it's their balls up, if you (assisted by a few geezers on a canal forum) give them a weight which will (by what I am reading at least) end up being wrong anyway, they will say 'thank you once you've paid the invoice for this little excursion we'll send a bigger crane...."

[NB Esk]

 

But my point is if they estimate it and send inadequate kit it's their balls up, if you (assisted by a few geezers on a canal forum) give them a weight which will (by what I am reading at least) end up being wrong anyway, they will say 'thank you once you've paid the invoice for this little excursion we'll send a bigger crane...."

Tell you what, if the crane people are happy to estimate the weight, I'll be doing backwards somersaults. Especially if they say "It's well under our estimations, so we'll only charge you........"

[Batavia]

 

But my point is if they estimate it and send inadequate kit it's their balls up, if you (assisted by a few geezers on a canal forum) give them a weight which will (by what I am reading at least) end up being wrong anyway, they will say 'thank you once you've paid the invoice for this little excursion we'll send a bigger crane...."

This depends on what type of contract you have with the crane company, who will normally use one of the two standard forms of contract. If it is a straight Crane Hire, then all the responsibilities and liabilities are yours. If you choose a Contract Lift, then the crane company takes on many of the responsibilities and liabilities (but not all). You obviously pay more for a Contract Lift.

 

Chris G

 

Chris G

[Guest]

This depends on what type of contract you have with the crane company, who will normally use one of the two standard forms of contract. If it is a straight Crane Hire, then all the responsibilities and liabilities are yours. If you choose a Contract Lift, then the crane company takes on many of the responsibilities and liabilities (but not all). You obviously pay more for a Contract Lift.

 

Chris G

 

Chris G

 

Sounds reasonable to me.

[mikevye]

Just fill the bath lower your boat in it measure the water displaced and you have the weight!

[steamraiser2]

As the title really. I need to find the weight of my boat, so I can organise the correct crane.

The background is that it's a 55 foot self build tug style, on hard standing. I did make a record of the weights of steel used but these were nicked by scrap metal thieves, along with vintage engine manuals, power tools, welding equipment, boat fittings & materials etc.

Brief details of the boat, 12mm baseplate, 6mm hull & 4mm cabin. There's also a vintage engine in the engine room. Fitout hasn't got much beyond battening & insulating, so it's basically a sailaway.

So, can anyone come up with a method of weighing it?

Assuming that you are not an Appointed Person (Lifting) you don't need to know the weight of your boat. Just get the crane hire company to send their APL round to measure and calculate the load to be lifted and from where and to where etc. Under the Contractors Plant Association (CPA) standard lifting contracts this will form the basis of a Contract Lift. They are wholly responsible for its safe execution not you. If you specifiy and direct the operation you are responsible for all consequential loss and damage. The legal and financial implications of this could ruin you if the lift goes pear shaped. I'm always a little concerned that people with little knowledge try and plan this. As a private hirer, should you proceed to manage and specify the lift yourself, you are liable for everything. Do the job through a contract lift and you are responsible for nothing. If the boat gets dropped under a contract lift the crane company insurer is liable for your loss and damage not you. Perish the thought of injury to members of the public etc. Easily run into millions.I know what I would choose!

[NB Esk]

Assuming that you are not an Appointed Person (Lifting) you don't need to know the weight of your boat. Just get the crane hire company to send their APL round to measure and calculate the load to be lifted and from where and to where etc. Under the Contractors Plant Association (CPA) standard lifting contracts this will form the basis of a Contract Lift. They are wholly responsible for its safe execution not you. If you specifiy and direct the operation you are responsible for all consequential loss and damage. The legal and financial implications of this could ruin you if the lift goes pear shaped. I'm always a little concerned that people with little knowledge try and plan this. As a private hirer, should you proceed to manage and specify the lift yourself, you are liable for everything. Do the job through a contract lift and you are responsible for nothing. If the boat gets dropped under a contract lift the crane company insurer is liable for your loss and damage not you. Perish the thought of injury to members of the public etc. Easily run into millions.I know what I would choose!

OK, thanks for this. Just the sort of advice I need. It's become much clearer what I need to do...

[koukouvagia]

This has been discussed many times on the forum. NB it's easier, I find, to use Google to locate past topics than struggling with the notoriously fickle forum search tool.

 

My contribution to the debate is here:

 

http://www.canalworld.net/forums/index.php?showtopic=18541&p=298506

 

However, the advice given in this present thread is probably sounder!

Edited September 8, 2013 by koukouvagia

[homer2911]

It's not often a 60f/t nb weighs over 15T generally a 70T crane is ample to lift this with a jib to around 12m A 70t crane doesn't cost much more than a 40 or 50 T crane. If there minimal jib you might get away with a 40T crane.

 

Crane companies will happily send out an assessor for a site visit. They've likely have done many boats before and know the score. Crane hire tends to rocket over 70T all to do with crane costs and weight of equipment on the road.

 

A 100T will cost ball park £1200 + v.a.t this is because it's a minimum day hire even if it's just one lift. 50 to 70T will be half that price.

My 62 ft boat weighs a few kilos under 20t, according to the weight gauge on the crane used at Oxley Marine a few years ago - one tonne per metre sounds about right then Edited September 8, 2013 by homer2911

[W+T]

I am not sure on the 1 ton per m rule, i recently got my NB lifted, its a 35 footer or 10.6m, it weights just 8 ton fitted out by the crane scales when lifted, and i was close when i worked out by the displacement, i worked out 8.6 ton, So i would say the ton per meter is a bit out.

 

As said above, if you are paying so much, and i bet the crane isnt cheap, the contractors should do all the checks and working out. Or they should do if not i would go elsewhere.

 

good look with it and like the boat

 

 

wolly

Edited September 8, 2013 by W+T

[David Mack]

Ok, I'll try that. The crane will need to stand maybe 15 feet behind where the photo was taken from.

 

You could always move the boat nearer to the crane position. Its not difficult. Some years ago I pulled a 57ft boat up a slipway using machine moving skates and a tirfor winch. I put some stout planks down to form a runway for the skates, then used a 5 tonne toe jack to lift each side under the engineroom and insert a skate, and the same again under the bow. Attached the tirfor to the gate post and she came up a dream. That was up a perhaps 20 degree slope, so would be on a doddle on level ground.

Edited September 8, 2013 by David Mack

[Old Son]

Contract lifts are very expensive. My 65' was over £2k for a contract lift and £495 with me in charge. The lift was fairly straight forward, the crane was about 15 metres from the boat and the lorry had access to drive under.

[MtB]

Crane weight gauges are notoriously innacurate anyway, so don't bank on them agreeing it weighs 14.9 tonnes when their cranes says otherwise even if you can prove it!

 

I always ask the weight when I get Aldebaran lifted, and I get answers ranging between 16 and 20 tonnes. There is no consistency.

 

I am also certain cranes have huge safety margins built into their certified lift capacities so if the boat is slightly 'over', the drive will probably proceed with the lift anyway.

 

I reckon all the youtube videos of cranes tipping over are because crane drivers are accustomed to overstressing their cranes on a regular basis and getting away with it, then getting complacent and overcooking it one day...

 

MtB

[Biggles]

I used this calculator when I was building my boat.

 

Linky

 

It's pretty spot on but will take you a bit to work out your surface areas but will be worthwhile.

 

I will try a file share of my weight spreadsheet.

 

https://docs.google.com/spreadsheet/ccc?key=0Avig0wcd3S8RdEZuTXlMdUpiUHlfemJXbC12dWY3a1E&usp=sharing

 

Let me know if it works please

Edited September 9, 2013 by Biggles