Ship crane

On Thu, 29 Apr 2010 19:52:13 +0100, kimsiddorn wrote:


Extra points for it being steam-powered? ;-)

What sort of reach does it need to have? I'd imagine quite a bit, and
that will probably impact things a lot - the boom will need to be
substantial, which means quite a big truck, significant stabilisers etc.

What about drop - does the transport truck always sit on dry land with
only a foot or two to the water, or are you sometimes dropping things
many feet over the side of a dock / pier etc.? (If the drop's always
quite small, I was just thinknig that something with a hydraulic lift,
but not necessarily a crane, might do the job instead)

Do you expect to take the crane with you on the transport truck, or does
it need to be self-propelled? If the latter, what sort of distances does
it need to travel?

Interesting problem, anyway...

Timber Routes in Knowle (on the web) might be selling / have already
sold a gantry on wheels that they were using for timber framing. Worth
an email, tell them I sent you. Handy for you too!

I'd say the cheapest way would be via an 'A' frame, girder and chain block.
I'd guess that it would need to be pretty high for the job in question.

Also maybe a large forklift. They come big enough to lift fully laden 20'
shipping containers so 3 tonnes is not much really.

Julian.

Timber derrick with hemp ropes and lots of warrior/manpower if you
want to stick to traditional principles for re-enactment?

            Would the boat be lifted from above using flat web straps,
or with it sat on a cradle?
 If you use straps transversely under the keel you will need to use a
spreader beam across each to prevent the weight of the boat crushing
the gunwales inwards, and probably two to keep them from sliding
together longitudinally. Unfortunately, all this adds weight and
height when they all meet at the apex.

What are the boats dimensions?
Would they fit on a “Roll-on – Roll-off=94 demountable plant flatbed?.

In a previous working life during the early the eighties I was
seconded to drive the company 15 ton RT mobile crane, and their 22 ton
Rusting Buggybus rigged as a crane, when required. I launched two
boats of a similar weight lifted from trailers, and one vice versa
(*), using a spreader frame.

(*)  Sorry, I can=92t think of a single word for the opposite of
=93launch=94 ?

Regards,
DJC

kimsiddorn wrote:

X-posted for possible replies from the denizens at
news:uk.rec.waterways .

--
MatSav

Sorry about the last message but, out of the blue google swapped all
its threads from our normal account (on yahoo) to the one the wife has
to have on Gmail to access some of the stuff that outlook express used
to handle but windows 7 does not. Blooding computer programmers!