Crane lifting a grp topped narrowboat concerns

[Karen Lea Rainey]

Hi, all,

I wonder if i should be concerned or not,

In the spring of next year my boat club do their annual crane lift out of the water whereby any maintenance and blacking etc can take place.

My concern is i have a 1974 45foot Teddesley built grp topped narrowboat, it is very sound on top with no leaks whatsoever from the roof or windows. Some 5 years ago the boat was rebuilt inside to fabulous new style design with beautiful oak veneers walls, cielings throughout,

The boat is pretty special inside and ive also recently painted it outside aswell( in part ).

 

My worry is if a crane picks up the boat in its slings, will a lot of pressure be put on the grp sides to any extent that may cause cracking or movement in the future and a leaking roof or windows.

 

Does anyone have any experience of seeing or hearing about a crane lifting a grp topped boat onto the adjacent ground to the waterway.

 

Or should i discount the fact of a shared cost of cranage (about £60 each) in order to go for the no boat stress dry dock method of blacking.

 

I would really appreciate anyones knowlegde on this practice. Thanks keith

[bizzard]

Hi, all,

I wonder if i should be concerned or not,

In the spring of next year my boat club do their annual crane lift out of the water whereby any maintenance and blacking etc can take place.

My concern is i have a 1974 45foot Teddesley built grp topped narrowboat, it is very sound on top with no leaks whatsoever from the roof or windows. Some 5 years ago the boat was rebuilt inside to fabulous new style design with beautiful oak veneers walls, cielings throughout,

The boat is pretty special inside and ive also recently painted it outside aswell( in part ).

 

My worry is if a crane picks up the boat in its slings, will a lot of pressure be put on the grp sides to any extent that may cause cracking or movement in the future and a leaking roof or windows.

 

Does anyone have any experience of seeing or hearing about a crane lifting a grp topped boat onto the adjacent ground to the waterway.

 

Or should i discount the fact of a shared cost of cranage (about £60 each) in order to go for the no boat stress dry dock method of blacking.

 

I would really appreciate anyones knowlegde on this practice. Thanks keith

Insist that they use a ''spreader frame'' which will avoid side pressure on the grp top, and indeed to some extent on the hull too.

[Phil Ambrose]

Biz is spot on, they MUST use a spreader, if they won't then don't lift.

Phil

[Karen Lea Rainey]

I'm afraid i dont know what a spreader frame is, previously they have used a 2 sling method, 1 put at the bow and 1 towards the stern, hence my concern. If there is no 'spreader' frame should i discount the option of a lift out.

[Alan de Enfield]

A spreader-frame is a big square of metal 'girders' that is as wide (or slightly wider) than your boat, this means that the weight of the boat is taken across the base rather than 'squashing' the sides together.

 

A 'standard' lift without a spreader frame is a bit like a pair of shears with the boat squashed between the 'blades' (straps)

 

I'll try and find a picture - back soon.

 

With a 'spreader' (Sides of boat not 'squashed')

 

 

Without a 'spreader' - Sides and edge of roof are 'squashed' and if boat is not ridged enough will collapse.

 

Edited October 24, 2016 by Alan de Enfield

[Karen Lea Rainey]

Got it thanks, i will insist or it wont happen, thanks very much all.

[Neil2]

If you have a glass top boat of that vintage and it really does not leak at all, dare I say you have something unique. I'd be wary of having it craned out, even with a spreader, it's false economy. There are better ways of getting a boat like this out of the water without risking flex in the hull/cabin.

 

I think I know the type of boat - does it have four windows each side with a small porthole in the centre?

[Karen Lea Rainey]

Definetley no leaks, I'm really happy with it and want to keep it that way.

[zenataomm]

At our club we have a 55ft nb with a GRP cabin.

It's a Frobisher with the sliding portion in the middle.

 

Our crane uses a spreader and we have had no problems whatever.

Whatever the boat I'd always insist on a spreader when craning.

[DHutch]

When out boat was lifted in, it was lifted without a spreader, but with long enough slings/chains they where almost as wide apart (fore-aft) as if they had have used a frame, and as far as I am aware, didnt touch the cabin.

 

That said, 25 years later we have not been lifted out since, preferring to use a drydock, which inherently gives better support and many would say less risk.

 

Launch photos: http://www.emilyanne.co.uk/gallerys/launch/index.htm

 

 

Daniel

[Karen Lea Rainey]

What a fabulous set of photos you recorded, a pleasure to see, thanks for sharing

[Mike Jordan]

There is always some risk of uneven support distorting the hull when a boat is taken out of the water, whether using a dry dock where the bostocks may not be level or the boat may have a slight curve, or using a trailer. By far the easiest way to damage it is to lift without a spreader frame, some crane operators will say "don't worry mate we will use a long set of lifting chains or cables" this no doubt reduces the squeeze to some extent but it's a stupid idea to lift anyone's pride and joy this way. In my experience the only real motive is to save the operator the job of rigging the spreaders or lifting frame, a job that takes about 15 minutes.