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  #16  
Old 10-24-2007, 05:02 AM
SAE140
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Quote:
Originally Posted by Basjan View Post
A good trailer design is a must for any small boat owner.
Locally a lot of boats are launched from the surf, and therefor we use "break neck trailers". The towbar of the trailer either swivels on the axle or on hinges independantly from the part of the trailer that supports and carries the boat. When the boat is secure on the trailer, the two parts are locked together with pins or bolts. This helps with the recovery of big boats upto and exceeding 26'.
Well, there's 'break-neck' and 'break-back' - the difference being where the break is made. Presumably 'break-back' trailers are legal in France, as the draw-bar itself is kept rigid ?

When considering trailers for my own boat, which is at the upper limit for these parts (UK) I decided to scrap the break-back trailer it came on, as it was a single-axle design (most are, it seems) and built a twin-axle piggy-back trailer ro replace it. With this piggy-back design, the road trailer itself never gets wet - only the launch dolly, which is equipped with the usual locating wands, and which is winched onto the trailer via detachable ramps.
But - it's probably not legal somewhere-or-other ...

Another project I've started work on, but not yet finished or tested is a low-water launch/recovery system. The idea of this system is to drop the boat off the trailer onto the bottom of the launch ramp at low water, so you'll be the first away on the flood. For recovery, you simply need to ground the boat somewhere on the slip then let the tide ebb away completely, then pick-up the boat whilst everyone else is down at the pub wondering how the silly sod that misjudged the tide is going to recover his boat ...
Only for those boats which can dry vertically, of course.

Colin
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  #17  
Old 10-24-2007, 07:47 AM
fcfc fcfc is offline
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Quote:
Originally Posted by SAE140 View Post
But - it's probably not legal somewhere-or-other ...

Do not laugth . You were rigth. The issue arose in france time ago. The dolly trailer was essentially for law ( and insurance companies ) a uncertified trailer. Use on private places such as shipyard ramp was OK. Use on public ramps was simply prohibited (...) and uninsured (much more annoying ).Since then law have changed to rename theses dolly "trailers" to "special handling equipment". Use is now allowed (and insured) on public places but with some constraints added. Mainly signaling and some kind of real parking brakes for the dolly trailer.

I guess your trailer look something like : http://www.go-neptune.org/Go550/Salon/Go-2.html
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  #18  
Old 10-25-2007, 09:09 AM
SAE140
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The basic idea is the same, but there the similarity ends. My dolly wheels are something like 14" diameter with solid tyres and fitted on 1" dia axles. I initially tested small diameter castors but they were a disaster - the damned things jammed in the expansion joints betwen the concrete slabs on the slipway.

I'd be interested to learn precisely *why* a wheeled load has been legislated against in France. Car transporters carry wheeled loads all the time ! I'm sure there's a way around the legislation (there usually is) even if this means jacking-up the dolly and replacing the round wheels with 'square' ones (if you know what I mean) - which could then be easily bolted to the trailer bed whilst in transit. That way the dolly doesn't exist - it becomes part of the trailer bed itself.

Fortunately, UK legislation is ok with wheeled loads providing they are secure. My dolly is substantially clamped to the bed when in transit, and the whole kit and caboodle is secured with 3 x 2-ton cargo straps.

But you raise an interesting point - which relates to something I wrote earlier. Newbridge boats offered a dolly-breakback trailer combination as an optional extra back in the 70's. Fully legal in Britain both then and now - but what is the legal situation if such a trailer is used in France ?

The whole trailer thing is inconsistent: British troops have been lugging around 1.5 ton *unbraked* trailers behind their Land Rovers for donkey's years without anyone commenting on it. But if you or I were to do this, we'd get pinched.

Colin
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  #19  
Old 10-25-2007, 11:21 AM
fcfc fcfc is offline
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I do not understand what you mean. It is not a law against wheeled loads. It is probably that someone just had a problem on a public parking or other public place towing with a car or something similar things like a "rolling craddle" or "hydraulic trailer". And the court just decided at that time that the vehicule was towing no more than an uncertified, unregistered, uninsured trailer. Things have been corrected now in the law. Court must call this "special handling equipment", not "trailer", and apply handling equipment regulations, not trailers regulations.

Now, back to technical issues. The problem of piggy back trailer is that it increases the load heigh while on the road, and increases the dead weight. Law (again ) generally limit a maximum gross weigth, not the load weight.

Pictures from www.rsa-fr.com web site.
Attached Thumbnails
Does this place need a 'trailering' section?-trailer1.jpg  Does this place need a 'trailering' section?-trailer2.jpg  Does this place need a 'trailering' section?-trailer3.jpg  

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  #20  
Old 10-25-2007, 11:35 AM
fcfc fcfc is offline
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Better have a serious coupling system...

A very serious one.
http://www.nauticaltrek.com/guides/g...on_bateau.html
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  #21  
Old 10-26-2007, 05:28 AM
SAE140
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Quote:
Originally Posted by fcfc View Post
I do not understand what you mean. It is not a law against wheeled loads. It is probably that someone just had a problem on a public parking or other public place towing with a car or something similar things like a "rolling craddle" or "hydraulic trailer". And the court just decided at that time that the vehicule was towing no more than an uncertified, unregistered, uninsured trailer. Things have been corrected now in the law. Court must call this "special handling equipment", not "trailer", and apply handling equipment regulations, not trailers regulations.

Now, back to technical issues. The problem of piggy back trailer is that it increases the load heigh while on the road, and increases the dead weight. Law (again ) generally limit a maximum gross weigth, not the load weight.
Are you saying that someone was towing a boat on a public road (or public place) using *just* the dolly ? Strewth - yes - of course that would be against the law here too.

When I said "But - it's probably not legal somewhere-or-other ..." I was referring to the combination trailer *as a whole* (not just the dolly) - to which you replied "Do not laugth . You were rigth." - and it seems that's where the confusion crept in.

This is a very good example of why it's impossible to discuss the trailer-sailing of boats without taking into account the legal requirements in different parts of the world.

Anyway - you're right about the increased load height, but this can easily be offset by a low-slung trailer base - my base runs about 13" above the road. Add another 7" to that for the dolly gives around 20" ride height - not at all excessive, and with a wheel width of almost 7'6" (the legal max) it's a pretty stable set-up. My dolly is similar to the left-hand picture you posted, but without the hull supports or draw-bar.

I fully agree that the increased weight of the combination trailer system is a negative, as it adds typically 25% to the gross trailer weight. But then, the brakes and bearings last forever - so like most boaty things, it's a trade-off situation, but never a perfect one.

Colin
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  #22  
Old 10-31-2007, 06:43 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
One tip I can suggest is to install a second ball mount on the front bumper.

Frequently folks will have a real difficult time in the backing portion of the boat launch

A ball on the front makes that last 50 ft much more bearable.

FF
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