Can anyone explain to me why when reversing an artic the trailor turns 1000 times more with full lock the opersite way then with the wheels straight and the cab kinked to push the trailor round.
senario: Pull up to reverse into a bay behind unit kinked to the right. I need the back of the trailer to go round to the right so left hand down right hand up. move back 1000 yards till the trailor starts to turn then straighten the wheels of the unit. push back 2000 yards till trailor is aimed at the bay kinda but at an angle. FULL LOCK opersite way ie left hand up right down to bring the unit in line with the trailor. move 1/2 an inch back trailor is now pointing 90 degrees to the bay in the wrong direction.
cooper1203:
Can anyone explain to me why when reversing an artic the trailor turns 1000 times more with full lock the opersite way then with the wheels straight and the cab kinked to push the trailor round.
senario: Pull up to reverse into a bay behind unit kinked to the right. I need the back of the trailer to go round to the right so left hand down right hand up. move back 1000 yards till the trailor starts to turn then straighten the wheels of the unit. push back 2000 yards till trailor is aimed at the bay kinda but at an angle. FULL LOCK opersite way ie left hand up right down to bring the unit in line with the trailor. move 1/2 an inch back trailor is now pointing 90 degrees to the bay in the wrong direction.
To my mind less stearing = less turning not more
What the hell is going on
Very difficult to describe or explain in “the written word” what is happening.
Training to get through the test isn`t the same as learning to reverse.
A few hours in a truck with someone patient and knowledgeable should teach you enough about real world reversing that you can practice in work later.
Practice. Ask and learn. Practice more.
If you are used to class 2 tou might fall into the trap of associating the steering position with the angle of turn.
On artic the angle between the cab and trailer determines the turn, the steering angle on the unit adjusts this to be more or less, but is secondary to the turn you are making.
njl:
On artic the angle between the cab and trailer determines the turn, the steering angle on the unit adjusts this to be more or less, but is secondary to the turn you are making.
^
Or to put it another way the unit’s drive/rear axle steers the trailer not the steer axle and that takes time and distance to change locks.
njl:
If you are used to class 2 tou might fall into the trap of associating the steering position with the angle of turn.
On artic the angle between the cab and trailer determines the turn, the steering angle on the unit adjusts this to be more or less, but is secondary to the turn you are making.
so less angle = less steering■■? in which case why does less angle = more steering as i am decreasing the angle of the unit to the trailor by full opersite lock but the trailer is carrying on spinning on a dime to the right (only time it does actualy turn with any speed)
You’re over thinking it, get the set up angle correct & you don’t need much steering input at all, if you’re finding you are going from full lock to full lock then you’re not setting it up correctly to start with.
You have to fight the urge to use steering wheel to compensate for your perceived lack of turning, not easy to understand when you first start out, but keep an eye on the pivot point (middle axle on a Tri) to really see how the trailers reacting.
Best thing you can do is set some cones out in a yard somewhere, (or just use empty parking spaces that you can clearly see the lines) practise your bay reverse but focus on the set up of trailer position & fight the urge to steer as much as possible.
njl:
If you are used to class 2 tou might fall into the trap of associating the steering position with the angle of turn.
On artic the angle between the cab and trailer determines the turn, the steering angle on the unit adjusts this to be more or less, but is secondary to the turn you are making.
so less angle = less steering■■? in which case why does less angle = more steering as i am decreasing the angle of the unit to the trailor by full opersite lock but the trailer is carrying on spinning on a dime to the right (only time it does actualy turn with any speed)
If you reverse with the unit at an angle to the trailer and even with the steer axle straight ahead that angle and lock v the trailer will increase.
If you want to take lock off the trailer or change it that takes time and distance with a surprisingly delayed action.
So if you’re finding that you’re oversteering the trailer then you’ve either left it late with the steering inputs and/or applied too much.
Try to get used to the idea that you only need to apply a small amount of opposite lock to start the turn.Then take it off early by bringing the steer back to straight and much earlier than you think.
cooper1203:
in which case why does less angle = more steering as i am decreasing the angle of the unit to the trailor by full opersite lock but the trailer is carrying on spinning on a dime to the right (only time it does actualy turn with any speed)
If you’re trying to straighten it all out from a right hand turn that isn’t ‘opposite lock’ on the steering it’s a right hand steering input.
Opposite lock would be left hand input which will increase the angle and the rate of turn of the trailer to the right.
If the trailer is outrunning the right hand steering input then it means you’ve applied too much left hand lock to start creating too much angle and/or you’ve left it too late to straighten it out with the right lock.
You’ve been on here for what seems like months asking questions about reversing. Sorry if this sounds harsh but if your not getting it yet maybe this jobs not for you. (Tin hat now on)
If you have a right kink on as you say, even with straight unit wheels the combination will increase bend.
If you imagine a corgi toy lorry on a carpet, say. Imagine having the unit at an angle and go back straight, it isn’t difficult to imagine what happens. The bend will increase until you are at right angles. This is why you must manipulate the bend you already have on, bearing in mind that by the time the trailer is in the correct place, the bend must be taken off.
You will see drivers sticking their heads out of the window watching the back of the trailer / wheels. This is what I do until I am almost in the bay and then the last bit with mirrors.
You will get there, it does take 6 months to a year, but I think it will click once you piece it together.
drover:
You’re over thinking it, get the set up angle correct & you don’t need much steering input at all, if you’re finding you are going from full lock to full lock then you’re not setting it up correctly to start with.
You have to fight the urge to use steering wheel to compensate for your perceived lack of turning, not easy to understand when you first start out, but keep an eye on the pivot point (middle axle on a Tri) to really see how the trailers reacting.
Best thing you can do is set some cones out in a yard somewhere, (or just use empty parking spaces that you can clearly see the lines) practise your bay reverse but focus on the set up of trailer position & fight the urge to steer as much as possible.
Agreed. I used to spend quiet nights at the garage practicing maneuvering with the shunter & test trailer. If you can do something like that you’ll soon get it. Just practice
You will see drivers sticking their heads out of the window watching the back of the trailer / wheels. This is what I do until I am almost in the bay and then the last bit with mirrors.
You will get there, it does take 6 months to a year, but I think it will click once you piece it together.
Didn’t someone on here say they opened the door and leaned out? Or witness it? Something like that lolol
You will see drivers sticking their heads out of the window watching the back of the trailer / wheels. This is what I do until I am almost in the bay and then the last bit with mirrors.
You will get there, it does take 6 months to a year, but I think it will click once you piece it together.
Didn’t someone on here say they opened the door and leaned out? Or witness it? Something like that lolol
I’m one who opens the door and leans out, not only do i find it more comfortable for the neck (i am ancient mind ) you get a better view and feeling for what’s going on.
It also has a safety aspect that should not be ignored, any sounds from the back will be reflected better from the door itself, if something were to happen or someone shout from the back end you are more likely to hear it and see it due to angle of view.
The only premises anyone has complained about this practice in well over 40 years was comet at Skem, some pen pusher got the arse saying it was dangerous, he couldn’t quite see the link between the number of deckers they ran with smashed in arse ends due to they’d all been rammed back repeatedly into the loading deck because people couldn’t judge when far enough back…leaning out the door gives that extra distance judgement too.
Its not a practice for everyone but works for some.
You will see drivers sticking their heads out of the window watching the back of the trailer / wheels. This is what I do until I am almost in the bay and then the last bit with mirrors.
You will get there, it does take 6 months to a year, but I think it will click once you piece it together.
Didn’t someone on here say they opened the door and leaned out? Or witness it? Something like that lolol
That’s what the old boy that taught me used to do!
No i didn’t follow that idea
) you get a better view and feeling for what’s going on.
