Why are tension couplings still legal?

[The Johnster]

It sounds like the sort of thing that ends in court orders and tagging...

[Il Grifone]

To answer the original question.

I have lobbied my MP and she is going to put forward a Private Member Bill to Parliament.

 

Titled: The getting Rid of Ugly Couplings Act 2018.

 

Far more important to get this into law rather that all this Brexit nonsense.

 

It will include all coupling apart from exact scale ones.

 

 

 

Hat, Coat, Door.

 

Line 2 -  She must be more use than our MP (It doesn't take much!)

 

Line 4 - Agree  (But there must be some secret agenda on Brexit.....)

 

 

Strays into politics again.... 

Edited May 5, 2018 by Il Grifone

[Compound2632]

I've posted this on another thread but hope it might also be useful here. In response to Regularity's observation that the bar of a tension-lock coupling prevents buffer-locking when propelling vehicles around tight curves, I've worked out the distance the bar needs to project beyond the buffer faces, D.This is a function of the tightest radius curve, R, the length over buffers, L, and the distance between the buffers, B:

 

D = L x B / (4R - 2B)

 

For a 4 mm scale model of an RCH 1923 12 ton mineral wagon, 19'6" = 78 mm over buffers, with 5'8" buffer centres, approx 23 mm, on Hornby first radius curve, R3 = 371 mm, the bar of the tension-lock coupling needs to project 1.3 mm beyond the buffer faces - say 1.5 mm for comfort. As has been observed elsewhere, the tesnsion-locks on some (many? most?) RTR wagons project much further than is necessary.

 

The formula for a bogie vehicle with the coupling rigidly attached to the bogie will be rather more complicated, as the bogie centres will come into it too.

[Il Grifone]

 

I've posted this on another thread but hope it might also be useful here. In response to Regularity's observation that the bar of a tension-lock coupling prevents buffer-locking when propelling vehicles around tight curves, I've worked out the distance the bar needs to project beyond the buffer faces, D.This is a function of the tightest radius curve, R, the length over buffers, L, and the distance between the buffers, B:

 

D = L x B / (4R - 2B)

 

For a 4 mm scale model of an RCH 1923 12 ton mineral wagon, 19'6" = 78 mm over buffers, with 5'8" buffer centres, approx 23 mm, on Hornby first radius curve, R3 = 371 mm, the bar of the tension-lock coupling needs to project 1.3 mm beyond the buffer faces - say 1.5 mm for comfort. As has been observed elsewhere, the tesnsion-locks on some (many? most?) RTR wagons project much further than is necessary.

 

The formula for a bogie vehicle with the coupling rigidly attached to the bogie will be rather more complicated, as the bogie centres will come into it too.

 

 

 Would I be correct in assuming that D is the greatest  distance between the buffer face centre line and the buffing face of the coupling since the latter is an arc?

 

I usually set couplings so that the buffers just don't touch on the tightest radius curve. (Tthis is the setting chosen by Meccano Ltd in their wisdom for Dublo stock. There's plenty of play as in tension this dimension extends to nearly 5mm.)

[Compound2632]

 Would I be correct in assuming that D is the greatest  distance between the buffer face centre line and the buffing face of the coupling since the latter is an arc?

 

Thinking about it more carefully, D should be the distance from the plane of the buffer faces to the point on the buffing face of the coupling at which contact is being made with the coupling on the next vehicle. It would be best to assume this is the extreme side of the coupling, i.e. D ignores the extra distance introduced by the arc of the buffing face - for the modern small tension lock couplings that's only going to add another 0.5 mm or so.

 

I usually set couplings so that the buffers just don't touch on the tightest radius curve. (Tthis is the setting chosen by Meccano Ltd in their wisdom for Dublo stock. There's plenty of play as in tension this dimension extends to nearly 5mm.)

 

In practice the empirical method is probably more reliable!

 

EDIT: corrected "puffer faces" to "buffer faces". We don't want Thomas et al. rubbing noses!

Edited May 5, 2018 by Compound2632

[andytrains]

 

I've posted this on another thread but hope it might also be useful here. In response to Regularity's observation that the bar of a tension-lock coupling prevents buffer-locking when propelling vehicles around tight curves, I've worked out the distance the bar needs to project beyond the buffer faces, D.This is a function of the tightest radius curve, R, the length over buffers, L, and the distance between the buffers, B:

 

D = L x B / (4R - 2B)

 

For a 4 mm scale model of an RCH 1923 12 ton mineral wagon, 19'6" = 78 mm over buffers, with 5'8" buffer centres, approx 23 mm, on Hornby first radius curve, R3 = 371 mm, the bar of the tension-lock coupling needs to project 1.3 mm beyond the buffer faces - say 1.5 mm for comfort. As has been observed elsewhere, the tesnsion-locks on some (many? most?) RTR wagons project much further than is necessary.

 

The formula for a bogie vehicle with the coupling rigidly attached to the bogie will be rather more complicated, as the bogie centres will come into it too.

 

Does it work?

My 3 links do.

[Compound2632]

Does it work?

My 3 links do.

 

Well, I'm a 3-linker these days but I wouldn't fancy my chances propelling through a cross-over of 2nd radius points!

[Ben Alder]

I used a sort of delayed 3 link system some time ago. It worked well but needed manual coupling and eventually went over to S&W's to provide this option.Here is a pic of it, and a link to my blog entry as I have no idea where the images are in my many files.

 

 

http://www.rmweb.co.uk/community/index.php/blog/62/entry-1544-delayed-action-3-link-couplings/

[ianLMS]

Dangling inappropriately is unfortunately one of the side effects i may have to put up with. Testing continues!

[Il Grifone]

Well, I'm a 3-linker these days but I wouldn't fancy my chances propelling through a cross-over of 2nd radius points!

 

Doomed to failure! Derailment is quite likely even with tension locks! 

 

EDit to insert 'even' which managed to disappear int cyberspace....

Edited May 8, 2018 by Il Grifone

[34theletterbetweenB&D]

...As has been observed elsewhere, the tension-locks on some (many? most?) RTR wagons project much further than is necessary...

 There is no published standard that I have ever seen that might inform us of the intended position. What appears to be the case is that the tension lock is positioned so that by use of a hand uncoupler the hooks may be lifted clear to achieve an uncouple while the vehicles are on the smallest radius curve in the manufacturer's track system. Plus a tad extra depending on state of the tide at the time the model was designed, and possibly other factors.

 

...I usually set couplings so that the buffers just don't touch on the tightest radius curve...

 Pragmatically - my ruling mantra in OO - my set up with (Bachmann) miniature tension locks is similar. The four wheel wagons up to 12' wb can have the bumper bar set so that the face is coplanar with the bufferheads. The wagons than buffer up on straight track when pushed, open out with 2mm between buffer faces when pulled - a good effect if representing loose coupled unbraked stock - and will negotiate curves down to the 24" found in a couple of yards. When  propelled on curves the inner buffers only are in contact, and the bumper bar acts to prevent bufferlock should the slack tolerances of OO allow the bufferheads to miss each other.

[Thunderforge]

Any children I've let near tension lock couplers have always used the same method of uncoupling. A wagon in each hand and a technique somewhere between a Chinese burn and a terrier tearing up a newspaper. Makes me cringe every time!

[The Johnster]

 There is no published standard that I have ever seen that might inform us of the intended position. What appears to be the case is that the tension lock is positioned so that by use of a hand uncoupler the hooks may be lifted clear to achieve an uncouple while the vehicles are on the smallest radius curve in the manufacturer's track system. Plus a tad extra depending on state of the tide at the time the model was designed, and possibly other factors.

 

 Pragmatically - my ruling mantra in OO - my set up with (Bachmann) miniature tension locks is similar. The four wheel wagons up to 12' wb can have the bumper bar set so that the face is coplanar with the bufferheads. The wagons than buffer up on straight track when pushed, open out with 2mm between buffer faces when pulled - a good effect if representing loose coupled unbraked stock - and will negotiate curves down to the 24" found in a couple of yards. When  propelled on curves the inner buffers only are in contact, and the bumper bar acts to prevent bufferlock should the slack tolerances of OO allow the bufferheads to miss each other.

 

Coplanar.  Kudos, 34, my mission for the day is to work that into a conversation...

[The Johnster]

This is drifting OT into a discussion about buffer locking and its corollary, coupling jam while drawing wagons, on tight curves, potentially a much more informative subject IMHO.

[eastglosmog]

Any children I've let near tension lock couplers have always used the same method of uncoupling. A wagon in each hand and a technique somewhere between a Chinese burn and a terrier tearing up a newspaper. Makes me cringe every time!

That's the method my 7 year old nephew uses!

[Compound2632]

Any children I've let near tension lock couplers have always used the same method of uncoupling. A wagon in each hand and a technique somewhere between a Chinese burn and a terrier tearing up a newspaper. Makes me cringe every time!

 

It's what they're designed for.

[Il Grifone]

Any children I've let near tension lock couplers have always used the same method of uncoupling. A wagon in each hand and a technique somewhere between a Chinese burn and a terrier tearing up a newspaper. Makes me cringe every time!

 

Is there any other way of uncoupling the da things without a tool or uncoupling rail?

 

This is drifting OT into a discussion about buffer locking and its corollary, coupling jam while drawing wagons, on tight curves, potentially a much more informative subject IMHO.

 

Not really OT I would have thought. The OP was a request why tension locks are still legal. A discussion on the science and maths of these and their competitors follows from this question. Unfortunately all couplings have their pros and cons and it's a matter of personal choice (or laissez faire).

Edited May 9, 2018 by Il Grifone

[newbryford]

The OP was a request why tension locks are still legal. 

 

Still waiting for the OP to return................

He never gave his own reasons for them being considered illegal.

 

Cheers,

Mick

[ejstubbs]

Still waiting for the OP to return................

He never gave his own reasons for them being considered illegal.

 

It's right there in the OP - he (or she, it's not clear) considers them a form of torture.  It was a joke (although I do understand what they're getting at).  And they did post on the thread again, it's #17 on the first page.  And yet it's sparked a thread of nine pages and counting full of people discussing for the umpteenth time on RMWeb their preferred coupling methods (ooh, er), including posts from what looked dangerously like a founder member of the Tension Lock Liberation Front, getting terribly upset about people dissing his favourite couplings.  As Il Grifone says, it comes down to a matter of personal choice (though anyone who argues that TLCs are preferable to Kadees because the latter aren't prototypical for UK stock needs to take a long hard look at their logic, IMO).

Edited May 9, 2018 by ejstubbs

[34theletterbetweenB&D]

It's right there in the OP - he (or she, it's not clear) considers them a form of torture.  It was a joke ...

And they are something of a joke, a 'standards free' zone as with some other aspects of OO RTR product.

 

 

Is there any other way of uncoupling the da things without a tool or uncoupling rail?

There's the Brian Kirby magnetic modification, applicable to the Bachmann version. What I really like with this mod is that the Kadee magnetic uncouplers operate it, and since I use Kadee for gangwayed coaches, there's a saving.

[Suzie]

I was the worlds greatest promoter of tension locks at one time. For the standard of track laying I could manage on my hardboard door baseboards they were the only coupling that would remain coupled under tension! The Playcraft/Jouef type just kept uncoupling.

 

I was really happy until the advent of the new-fangled 'Narrow' tension locks and the comedy close-coupling devices. It all went horribly wrong and something which had been hitherto exceptionally reliable was reduced to completely useless.

 

1. You cannot now just couple up without jiggling the hooks so they actually hook over the bar. Mostly they go to one side or the other.

 

2. The hooks regularly fall off, especially on long heavy trains. In the old days it was the tension that kept them coupled - alas no more.

 

3. The wobbling from side to side of the narrow coupler bars makes them useless as a buffing plate for propelling moves. The old rigidly attached wide couplers made propelling at full speed of ten coach trains no problem at all.

 

4. Different length hooks mean that any bump in the track such as going over a baseboard join is likely to see at least one of the hooks bounce and land outside of the 'D' which then puts side force on the coupling when negotiating a curve.

 

For a while I upgraded new NEM stock with big 'D' tension locks, but as I ended up treating nearly all stock it seemed utterly pointless, I might just as well fit a more discreet coupler like the Kadee...

[ianLMS]

Here is my attempt at a magnetic coupling system for 4mm. It works both push and pulling. I will start a new thread as this is probably not the right place for it. Cheers.

[rocor]

Here is my attempt at a magnetic coupling system for 4mm. It works both push and pulling. I will start a new thread as this is probably not the right place for it. Cheers.

 

For double the cost in magnets, you could probably also join the brake hoses.

[Steamport Southport]

Tension Lock Liberation Front, getting terribly upset about people dissing his favourite couplings. 

 

Splitter!

 

 

Which is what most couplings do anyway.   

 

 

 

 

Jason

[ianLMS]

For double the cost in magnets, you could probably also join the brake hoses.

I have been looking at the hoses as well but so far its complicated the issue as the hoses get attracted to the couplings etc and even if using opposite polarity they still find away of going where they shouldnt. Not given up yet though!!