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How Do We make "A" Frames Better


enodreven

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Hi, Everyone

 

What I really find quite strange that when most questions are asked on any of the motorhome Internet forums everyone tries to provide helpful suggestion s on ways to overcome the problems EXCEPT WHEN "A" FRAMES ARE MENTIONED everyone comes out with the same old stuff regarding the legalities, and even to the extent of some people finding enjoyment in trying to ridicule people who use them WHY ???

 

What would be interesting and a lot more helpful is to put all of the expertise's that exist on this site into finding a method for making them legal. as from all of the information I have read it does seem from a motorhomers point of view if these could be made legal then they would become a much more used resource as they certainly are more user friendly than a trailer and so far no one appears to be saying they are dangerous it appears the only problem if you chose and "A" frame with an overrun device operating a cable braking system is one of reversing it and I certainly know quite a number of people who tow so called legal vehicles that cannot reverses them ?? .

 

So come on lets examine what would need to be done to make them legal and then lets put all of our minds together to overcome the problems please don't let us get bogged down on the legalities.

 

If you actaully look at one with a overrun cable braking system and hand brake etc. and assume that they can achive the minimum braking affect that is required ? without the servo operational what would need to be done to make this legal and far more important HOW WOULD YOU DO IT

 

If I haven't explained myself correctly please don't start nit picking I am sure you can all understand what I am trying to say

 

So come on stop quoting the legal system put your heads together and find a method of making them legal.

 

Brian

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You have set quite a challenge here Enodreven!

 

The problem as I see it is complying with the braking requirements, i.e. the over run brakes. If these were operable on the car you would not have any brakes when reversing the car. In the same way as the brakes dont work on a caravan when parked facing up hill. I speak from experience on having my caravan running of the ramps when I pulled it up them instead of pushing it up the ramps!!

 

I think a compromise between atrailer and A frame is the best way forward. If you can visualise the the little frames that car recovery firms use to lift the front wheels of a car off the ground, this could be adapted to give you a two wheel dolly that could have the required braking mechanism. Some form of simple hand operated hydraulic jacking to push the dolly wheel down and lift the cars wheels off the ground and you have a method of towing without a trailer and meets the braking requirements.

 

Mean time I will use my trailer as it can also move furniture, garden sheds and whatever!!

 

VoH

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Hi,

 

I think the things you are talking about are called "Dollies" and from what I have read they are illegal other than for recovery ?

 

The only thing that seems to keep coming up regarding "A" frames is the inability to reverse them due as you say to the different braking arrangements.

 

I am not sufficiently up on the trailer legislation regarding the methods that can be adopted for unlocking the brakes on a trailer when it is reversed I believe that caravans etc use a special type of cam operation that unlocks the brakes when the wheels are reversed and as you say for obvious reason that cannot be employed on car.

 

The question is are the regulations so tight that this cam type arrangements is the only thing that can be used as it would seem if it is then they are constricting the market ? however if the regulations are like most regulations open to allow the market to operate then perhaps there are alternative devices that can be manufactured to comply ??

 

That's where I am asking the knowagable people on hear to look into this with open minds and perhaps hopefully design something that will help fellow motorhomes in using "A" frames

 

Hope that makes sense

 

Brian

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Hi,

 

Why this type of recovery unit is legal or illegal and the same with an "A" frame i do not know and what constitutes recovery and actually taking vehicle with you again I don't know.

 

All I do know is that the legal issues always seems to cloud the discussion and that's why i tried to structure the thread in the way i did as nearly everyone on the Internet forums i use want to help and will go to extreme lengths sometimes just to help someone out, but when "A" frames are raised all we seem to get is the legal issues raised and i really think that if we all put our heads together we could come up with devices that would meet the regulations and make the use of "A" frames

 

 

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Hi,

 

Thanks for the link

 

I looked at the ukcampsite link you gave and it stated that 71/320/EEC covers auto reverse braking systems and couplings. I did a Google on this reference number and found this site

 

http://ec.europa.eu/enterprise/automotive/directives/vehicles/dir71_320_cee.html

 

I started to read through the documents and I don't seem to be able to find any specific mention within the main document or the supplemental changes of the need to have automatic brakes that will allow the vehicle to reverse ?

 

Obviously this needs to be able to be completed but its the automatic part that is the real concern, as in the orginal documents a drivers mate was acceptable for control purposes ? that's not to say we all want to have "motorhome mates" LoL but it does start to question some of the information that has been raised as to the method of releasing the brakes before affecting a reverse maneuver.

 

I will continue to search the documents but if anyone knows where within the EEC legislation this can be found I would be grateful

 

Brian

 

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Hi Brian,

 

Whilst everyone (or most) would agree with what you are saying, you simply can't disregard the legal side of things. It's like saying that we should discuss the driving of heavier and larger motorhomes , but disregard the need for LGV licences etc.

 

There are many different types of designs available, but as stated they are for recovery purposers only, this means using them for the shortest possible distance or time. C&U regulations are a nightmare, and the only real way round your dilema is to make a working prototype and apply for type approval for use on a public road.

 

Even if we/you achieved this, it would still be of no use for us if we travelled abroad, unfortunately, if the French or German authorities decide that they are illegal to use, then we have no redress, and as much as we dislike their rulings, we must abide by them or face the consequences.

 

We have been down this road before, but as I said, unfortunately you just cannot dismiss the legality of something, just because you dislike the ruling, and that's why you cant really have this discussion without bringing it up.

Sorry, but good luck in your quest.

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Hi,

 

The tow car and trailer must be able to be reversed without the driver leaving his cab. The easiest way to achieve that is for the driver to pull a bit of string to engage the reverse detent lever used many years ago. A more compicated way would be to activate the detent lever with a solenoid fired by the reverse lamp switch.

 

On a simple trailer, use twin leading shoes, which become virtually useless when reversing. You just overpower them. But that no good for A-frames.

 

Add another slave cylinder to the tow car braking system. When towing, push the piston right home, and fit a master operated by the slave, connected by braided hose to a slave that pushes against the towed car's master cylinder. Press pedal in tow-car, and you operate all eight brakes.

If you need a vacuum for the towed cars brakes, it shouldn't be difficult to connect the cars together with a hose. Or use an electric vacuum pump connected via the 7-pin socket.

 

Fit your van with a recovery spectacle, same as the rescue services do. Use the above system to operate the towed car brakes...unless it is a very light car, and the REAR AXLE MAM is under 750kg

 

602

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W3526602 - 2007-09-19 6:13 PM

 

Hi, W3526602

 

Thanks for the input as for your

 

The tow car and trailer must be able to be reversed without the driver leaving his cab. 602

 

I have heard this before several times but as i said above i have been trying to read the legislation that apparently covers this particular subject

 

71/320/EEC covers auto reverse braking systems and couplings

 

but so far I haven't been able to find any mention of it albeit there is still a lot to read, do you know where it is written in the legislation or anyone that knows where it can be found in the legislation as I would be very grateful for any help in finding it, i have put a link to the legislation on one of the threads above

 

Thanks

Brian

 

 

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Brian,

I dont se what your problem with my reply is, you asked how we can make them legal ,yet you dont want to discuss legalities.

 

like I said in my previous post, you need to design and build one and apply for type approval. But this wont help on the continent will it.

For the record, I dont care if they are legal or not, I wouldn't use one, but I honestly understand those who want to.

 

The construction and use regulations lay down the guidelines for design, practicalities mean you will probably have to get out of the car to engage a lock-out system for the brakes, As they inevitably wil be pressure activated via a piston design on the frame.

 

As I said, good luck, but please dont slate peoples replies, when they only say what you've asked of them.

 

 

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Hi,

 

I really don't want to get into an argument over this but I really thought i had made it clear at the beginning that i didn't want the legalities of use of "A" frames raised in this topic as they have been flogged to death so many times that i thought this may be an opportunity to get the knowledge people on this site to actually put there heads together and perhaps design a "A" frame that met all of the requirements.

 

I am sorry if it wasn't clear enough , but just to try and make it clear now, please do not raise the legalities of the use of "A" frames either in the UK or Europe or whether you would use one or not. This topic is just to see if we can find methods of overcoming some of the obstacles that have been raised regarding the use of "A" frames

 

Hope that helps

 

 

 

 

donna miller - 2007-09-19 6:57 PM

 

Brian,

I dont se what your problem with my reply is, you asked how we can make them legal ,yet you dont want to discuss legalities.

 

like I said in my previous post, you need to design and build one and apply for type approval. But this wont help on the continent will it.

For the record, I dont care if they are legal or not, I wouldn't use one, but I honestly understand those who want to.

 

The construction and use regulations lay down the guidelines for design, practicalities mean you will probably have to get out of the car to engage a lock-out system for the brakes, As they inevitably wil be pressure activated via a piston design on the frame.

 

As I said, good luck, but please dont slate peoples replies, when they only say what you've asked of them.

 

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There are 2 methods "get the law changed" and the only possible solution that I can figure ouy is.. You will have to invent a system ,operated by the act of selecting reverse on your car,which will then operate a locking mecanism to lock the over run brake on the A-Frame..I should imagine something solanoid activated......Over to you to make it work I only think of these ideas,usualy while in the smallest room. :D :D
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First to answer your question on how to make an A frame legal, the answer I believe is not over run devices but a modified version of system used on artic's (and some farm trailers) I'm sure if someone would like to put there mind to it a system could be made to work, but I feel the cost would be high, as both van and car hydraulics would require mods.

 

Second my reservation, how will you reverse it? as I understand it the front wheels 'uncentre' themselves. I regulary tow trailers, often with vehicles on, loading and unloading is simple, reversing is a doddle, its a tried tested system that works well, the only gain that I can see to an A frame is on site storage of trailer, is this a problem? or am I missing the point?

 

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The technicalities of making the towed car's brakes not operate in reverse is the easy bit but I'm afraid Brian , whether you like it or not, its all academic until such time as the trailer law is changed to allow it to be done. Current trailer law (yes I know you specifically asked us to avoid the legal issues but I don't think you can ignore the law) requires that the trailer brakes be operated by an over-run coupling and that they automatically become dis-engaged during reversing manouvres. without resorting to modifying the towed cars hydraulic circuits or electrical devices (which are expressly forbidden by trailer law) I don't see how you can do it.

 

Besides which how are you going to control the steering of the towed car during your reversing manouvre????

 

D.

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Hi,

 

I'm guessing that the legislation tells you what to do, and Type Approval tells you what you can use to achieve it.

 

OT...the Law says you must have seat belts, so there is no point in trying to invent a better way of protecting passengers, you won't be allowed to use it.

 

I THINK the law says the trailer brakes must allow the trailer to be reversed. I wonder if it says the trailer must be able to be steered while being reversed? How many of us here plan their route so they don't NEED to reverse?

 

While travelling frontwards, the A-frame controls the steering wheel. Presumably the same applies in reverse.....if the driver is skilled enough.

 

602

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Hi, and thanks everyone for their contributions and Colin I don't think you have missed the point I really do think the size and storage is the real advantage/disadvantage ? I am sure if they could make a folding trailer that would work as well.

 

Dave,

 

I know you are quoting the trailer regulations but have you actually seen the section of the legislation that states what you are quoting, only I have been reading the actual documents that are suposed to cover this and I can't find any specific references to the methods that can be employed to make the vehicle reverse, if you do know where within the legislation the relevant parts are please let me know as its taking hours and hours to read through ?

 

I posted this earlier and it may explain my problem

Thanks for the link

 

I looked at the ukcampsite link you gave and it stated that 71/320/EEC covers auto reverse braking systems and couplings. I did a Google on this reference number and found this site

 

http://ec.europa.eu/enterprise/automotive/directives/vehicles/dir71_320_cee.html

 

I started to read through the documents and I don't seem to be able to find any specific mention within the main document or the supplemental changes of the need to have automatic brakes that will allow the vehicle to reverse ?

 

Obviously this needs to be able to be completed but its the automatic part that is the real concern, as in the orginal documents a drivers mate was acceptable for control purposes ? that's not to say we all want to have "motorhome mates" LoL but it does start to question some of the information that has been raised as to the method of releasing the brakes before affecting a reverse maneuver.

 

I will continue to search the documents but if anyone knows where within the EEC legislation this can be found I would be grateful

 

UPDATE ON THE POSSIBLE STEERING PROBLEM

 

Oh and as for the steering assuming you were allowed to get out of the vehicle before starting the reverse manuover would it work if you could lock the steering so as the front wheels were inline with the rears, i know this may make the tyres scrub, but some of the larger 4 wheeled trailers have a similar wheelbase to say a smart car ? what do you think ? I have never towed anything ?

 

 

 

 

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Brian,

 

THE LEGISLATION:

 

Sorry, but you have just asked! I quoted the relevant clauses in my articles in MMM about towing some time ago. No piint in looking at the EU directives, as you now need to look at their versions incorporated into UK Law. The relevant bits are contained in:

 

- UK Road Vehicles Construction and Use Regulations 1986, as copiously amended since

 

- UK Road Vehicles KLighting Regulations 1989, as also amended

 

together with relevant Road Traffic Acts and Driver Licensing Regulations.

 

The first is the most important and contains most of the trailer law. The clauses Dave Newell and I have been quoting are all inthere, they are totally unambiguous, and we have not been mis-quoting or over-simpifying them.

 

If you really, insis, I will go beck to my article preparation archives and dig out the relevant cluase numbers. However, everything since about 1988 is available online (which means the original 1986 Regulations are not, but all the emendments are). Or go to you nearest big library and they will have all the various compendiums to examine - I know, I've done it.

 

Have fun!

 

Mel E

====

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Hi, Mel E thanks for the information,

 

I wasn't saying it wasn't there it was just that i have been reading the 71/320 and its amendments and still can't find the reference, but as you have now explained its more important to examine what versions have been incorporated into UK Law.

 

Do you have any links to the online amendments and if you could dig out the relevant clause numbers? i would really appreciate it

 

Is there a way of finding your orginal document,

 

Thanks

 

Brian

 

Mel E - 2007-09-20 11:31 AM

 

Brian,

 

THE LEGISLATION:

 

Sorry, but you have just asked! I quoted the relevant clauses in my articles in MMM about towing some time ago. No piint in looking at the EU directives, as you now need to look at their versions incorporated into UK Law. The relevant bits are contained in:

 

- UK Road Vehicles Construction and Use Regulations 1986, as copiously amended since

 

- UK Road Vehicles KLighting Regulations 1989, as also amended

 

together with relevant Road Traffic Acts and Driver Licensing Regulations.

 

The first is the most important and contains most of the trailer law. The clauses Dave Newell and I have been quoting are all inthere, they are totally unambiguous, and we have not been mis-quoting or over-simpifying them.

 

If you really, insis, I will go beck to my article preparation archives and dig out the relevant cluase numbers. However, everything since about 1988 is available online (which means the original 1986 Regulations are not, but all the emendments are). Or go to you nearest big library and they will have all the various compendiums to examine - I know, I've done it.

 

Have fun!

 

Mel E

====

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Hi,

 

I had considered towing with an A-frame, with the towed cars steering locked all the time. And yes, it will provoke some aggressive tyre wear. BUT, if that set up complies with the regulations, would the regs prevent you unlocking the steering?

 

Another point to consider is the A-frame pushing the tow car's rear up or down under heavy braking. Which way would depend on the geometry of the A-frame. I was once towed in a car with no brakes, but no problem cos I was on a solid bar. Wrong, the weight of my car actually pushed the rear of the tow car sideways.

 

But I see nothing inherently unsafe with A-frames, provided the driver acts accordingly. Similar to all those Suzuki 4x4 that were supposed to fall over at the next corner. How many articulated lorries fall over, and why?

 

602

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602,

 

Locking the steering would probably cause dangerous heat build-up in the tyres. And the law is quite clear - you cannot unlock it manually in order to reverse.

 

You are perfectly right about the car pushing under or above the towing vehicle. I read a genuine story in a club newsletter of a man who towed his old Saab with a new one to get it to the garage and wrote off both when one submarined under the other.

 

Unlikely given the weight of a motorhome, but it is important that the A-Frame is level.

 

Mel E

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