Juddian:
Nomi’s motor as pictured above i would expect is rock solid unshakeable on the road
The ride is completely different depending on how it’s configured. The most hilarious is when I’m up to 26 tons with the moffett but without the drag. Because it’s on air up front it wallows like a coach. If I jab on the brakes hard enough it bottoms out! With the drag it’s completely different and as you say very smooth.
I would say that super singles up front probably aren’t a good thing because they’re heavier so transmit more jolts through the steering maybe?
Juddian:
Nomi’s motor as pictured above i would expect is rock solid unshakeable on the road
The ride is completely different depending on how it’s configured. The most hilarious is when I’m up to 26 tons with the moffett but without the drag. Because it’s on air up front it wallows like a coach. If I jab on the brakes hard enough it bottoms out! With the drag it’s completely different and as you say very smooth.
I would say that super singles up front probably aren’t a good thing because they’re heavier so transmit more jolts through the steering maybe?
This , every wagon n drag drives different ,I’ve driven mid lift lorry crane at rear with 3 axle trailer ,2 axle lorry 3 axles trailer ,3 axle trailer rear lift lorry ,2 axle spread axle trailer rear lift lorry crane behind cab ,hitch’s in different places ,different length necks ,they all perform forwards and reverse in a different manor .
Juddian:
The big benefit in wag’n’drag (assuming the wagon is big and long and heavy enough to control the drag) is the length of prime mover wheel base leading to ride quality that artic drivers can only dream of…ie Nomi’s motor as pictured above i would expect is rock solid unshakeable on the road?
Not so keen on this century’s car transporter designs where a standard tractor unit is fitted with a drag towing hitch, obviously behind the drive axle, towing a bigger longer and heavier trailer with the axles only just behind the centre line, not uncommon to find the tail wagging the dog on those, most unstable combination i’ve ever driven.
A frames are a game changer regarding the tail wagging the dog situation.IE the turntable and bogie/dolly is effectively the same thing as the superimposition of the semi trailer onto an artic tractor unit.IE the weight imposed over the bogie keeps it line just as in the case of an artic tractor unit so little if any lateral movement applied to the A frame at point of coupling just as the much heavier trailer doesn’t wag a tractor unit.That’s why the Swedes etc can happily pull a 40t + trailer with a 25t rigid.You couldn’t do that with just a direct coupling behind the prime mover’s drive axle because the nose weight of the trailer uses it as a fulcrum point and lifts the prime mover’s steer axle.While at the same time the lateral and directional stability of the trailer is all dependent on the prime mover’s steer axle stopping the trailer from revolving the prime mover laterally around it’s drive/rear axle/s.Which is mainly what causes the tail wagging the dog,light steer axle and the trailer then trying to revolve the whole lot around the drive/rear axle of the prime mover.In addition to the problem of a tail heavy trailer creating the opposite effect of a light drive axle combined with a lateral force times distance effect acting on the pin thereby also swinging the outfit from side to side from the rear.
The close coupled design being just a bigger version of a typical car and caravan set up in that regard with all the same flaws and dangers.Which is how we ended up with a close coupled drawbar outfit on its side facing southbound in the northbound carriageway of the M6 and its driver having totally lost his bottle to ever drive a truck again and I took over his run, before the welcome move to A frames.
What buttocks ,your caravan mite wag your car but you’ve got to load a lorry n trailer pretty wrong for a lorry to do it .
Juddian:
The big benefit in wag’n’drag (assuming the wagon is big and long and heavy enough to control the drag) is the length of prime mover wheel base leading to ride quality that artic drivers can only dream of…ie Nomi’s motor as pictured above i would expect is rock solid unshakeable on the road?
Not so keen on this century’s car transporter designs where a standard tractor unit is fitted with a drag towing hitch, obviously behind the drive axle, towing a bigger longer and heavier trailer with the axles only just behind the centre line, not uncommon to find the tail wagging the dog on those, most unstable combination i’ve ever driven.
A frames are a game changer regarding the tail wagging the dog situation.IE the turntable and bogie/dolly is effectively the same thing as the superimposition of the semi trailer onto an artic tractor unit.IE the weight imposed over the bogie keeps it line just as in the case of an artic tractor unit so little if any lateral movement applied to the A frame at point of coupling just as the much heavier trailer doesn’t wag a tractor unit.That’s why the Swedes etc can happily pull a 40t + trailer with a 25t rigid.You couldn’t do that with just a direct coupling behind the prime mover’s drive axle because the nose weight of the trailer uses it as a fulcrum point and lifts the prime mover’s steer axle.While at the same time the lateral and directional stability of the trailer is all dependent on the prime mover’s steer axle stopping the trailer from revolving the prime mover laterally around it’s drive/rear axle/s.Which is mainly what causes the tail wagging the dog,light steer axle and the trailer then trying to revolve the whole lot around the drive/rear axle of the prime mover.In addition to the problem of a tail heavy trailer creating the opposite effect of a light drive axle combined with a lateral force times distance effect acting on the pin thereby also swinging the outfit from side to side from the rear.
The close coupled design being just a bigger version of a typical car and caravan set up in that regard with all the same flaws and dangers.Which is how we ended up with a close coupled drawbar outfit on its side facing southbound in the northbound carriageway of the M6 and its driver having totally lost his bottle to ever drive a truck again and I took over his run, before the welcome move to A frames.
What buttocks ,your caravan mite wag your car but you’ve got to load a lorry n trailer pretty wrong for a lorry to do it .
As I said ‘all the same flaws and dangers’.
Yes the thing was loaded ‘pretty wrong’ by all accounts just like a car and caravan outfit has to be but not exactly difficult to get wrong.While we’re talking pre loaded and sealed box bodies and warehouse staff more if not solely used to the easier weight distribution requirements of artics at the time.Having said that I still often had to argue about the weight distribution of the outfit even after that also having to start earlier to keep an eye on what they were putting where before they closed it.Although to be fair next day mixed freight and parcels all being loaded during the same limited time window on a busy cluttered loading dock isn’t something which can easily be left to one side while waiting for something the right weight to put in exactly the right place.Bearing in mind that was also a 4 axle outfit not 5.Which as I said is easily fixed by going for far more stable and much less weight distribution critical A frame type outfits to the point where as I said even pulling a trailer of double the weight of the prime mover won’t bother it.
So there we have it Tufnells and UPS still as far as I know and generally still the Scandinavians and Germans and Dutch and Swiss at least.The rest are amateurs who’d prefer to end up as he did,or at best get nicked for a drive axle overload sooner or later,than to learn how to reverse a ‘proper’ lorry n trailer.Bearing in mind that’s what the OP is clearly referring to.
i remember dhl running wagon and drags out of bridgwater and they had a roller door on the front of the drag and a ramp so they could load/unload both without dropping the trailer.
I used to run a 6 wheel tipper with a trailer that carried the plant. Tar machines or 3cx. Sometimes all on it. Never had any snaking even when going downhill at 75.
Was a scania tipper. Was a monster for pulling. Manual box as well
xamtex:
i remember dhl running wagon and drags out of bridgwater and they had a roller door on the front of the drag and a ramp so they could load/unload both without dropping the trailer.
Pretty sure DHL still use exactly that arrangement on the NHS contract.
xamtex:
i remember dhl running wagon and drags out of bridgwater and they had a roller door on the front of the drag and a ramp so they could load/unload both without dropping the trailer.
According to Donbur who specialise in the Uk drawbar combos they say a box body can get 28 Uk pallets. Where a hox body artic trailer usually takes 26. They have the option for curtainsiders aswell.
Odd days:
Can you get more cubic space on a close couple as opposed to an A frame set up ? Just wondered.
No. Same length.
I reckon using the same overall max length, you should get slightly more load volume on a close coupled non A framed lorry and drag, don’t some of them have a trick coupling, when turning the distance between wag and drag increases and as it straightens up the drag inches closer to the wagon?
With a A frame i would have thought (but my experience of A frames is over 30 years ago) the trailer would have to be further from the wagon all the time?
Just my thoughts here, happy to be wrong if i am
Apart from anything else, the A frames while you can get good at maneuvering them, are not as versatile for quick reversing in and out of places as a normal wag n drag, i certainly wouldn’t want one again.
brianchalkyshaw:
According to Donbur who specialise in the Uk drawbar combos they say a box body can get 28 Uk pallets. Where a hox body artic trailer usually takes 26. They have the option for curtainsiders aswell.
7.6 m body either way leaving at least around almost 12ft spare within overall 60ft so at last one extra row of 1m long pallets than a 45ft artic trailer and enough space for an A frame to work.
Odd days:
Can you get more cubic space on a close couple as opposed to an A frame set up ? Just wondered.
No. Same length.
I reckon using the same overall max length, you should get slightly more load volume on a close coupled non A framed lorry and drag, don’t some of them have a trick coupling, when turning the distance between wag and drag increases and as it straightens up the drag inches closer to the wagon?
With a A frame i would have thought (but my experience of A frames is over 30 years ago) the trailer would have to be further from the wagon all the time?
Just my thoughts here, happy to be wrong if i am
Apart from anything else, the A frames while you can get good at maneuvering them, are not as versatile for quick reversing in and out of places as a normal wag n drag, i certainly wouldn’t want one again.
Max length is 18.75m for both in a straight line. I have seen systems that enable the drag to come closer to the wagon on many European reg Drags. Pushing the drag further back on corners & pulling it closer in a straight line, but that mainly for better air flow over the whole combination of wagon and drag.
Odd days:
Can you get more cubic space on a close couple as opposed to an A frame set up ? Just wondered.
No. Same length.
I reckon using the same overall max length, you should get slightly more load volume on a close coupled non A framed lorry and drag, don’t some of them have a trick coupling, when turning the distance between wag and drag increases and as it straightens up the drag inches closer to the wagon?
With a A frame i would have thought (but my experience of A frames is over 30 years ago) the trailer would have to be further from the wagon all the time?
Just my thoughts here, happy to be wrong if i am
Apart from anything else, the A frames while you can get good at maneuvering them, are not as versatile for quick reversing in and out of places as a normal wag n drag, i certainly wouldn’t want one again.
Max length is 18.75m for both in a straight line. I have seen systems that enable the drag to come closer to the wagon on many European reg Drags. Pushing the drag further back on corners & pulling it closer in a straight line, but that mainly for better air flow over the whole combination of wagon and drag.
Dentressangle and others used to have many of these, but I haven’t seen many new ones lately.
Didn’t they change the rules to exclude these outfits with the extending bar? I’m certainty not sure about that though?
Franglais:
Max length is 18.75m for both in a straight line. I have seen systems that enable the drag to come closer to the wagon on many European reg Drags. Pushing the drag further back on corners & pulling it closer in a straight line, but that mainly for better air flow over the whole combination of wagon and drag.
Dentressangle and others used to have many of these, but I haven’t seen many new ones lately.
Didn’t they change the rules to exclude these outfits with the extending bar? I’m certainty not sure about that though?
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Check out the photo in the first OP post.That’s as close coupled as it needs to be and it generally gets in either case.It really is obvious that the fixed bar centre axles close coupled trailer configuration has loads of flaws,regarding weight transfer and weight distribution and stability issues,and no real advantages whatsoever.
i definitely get 1 more dumper onto the drawbar than the artic , on the drawbar i can do a max load of 3 x 9 tonne dumpers plus a 3 tonne dumper , on the artic its just 3 x 9tonne dumpers.
i ran a donbur swap body drawbar at salvesen , with the double deck bodies on it was 4 pallets extra over the artic double deckers or you could put 2 x 24’ distribution bodies on , or a combination of both. i usually ran it with a distribution body on the front and a double deck on the back.
before the welcome move to A frames.
