100 wagon challenge

[Golden Fleece 30]

https://www.youtube.com/watch?v=Vmhl2orGFLw

 

this was an out-of-the-box Roco loco

 

Andi

I doubt those coaches are very heavy, sorry but if they are plastic it is not really that impressive when my Dorchester pulled all the heavy metal and glass built Exleys, it would have pulled these with ease, and more.

 

In 1962 a Hornby Dublo Deltic was demonstrated pulling 28 of their heavy super detailed coaches that were non pinpionted.

 

Garry

[Il Grifone]

The maths for calculating the tip over point is quite complicated and involves vector diagrams and such like....  Factors involve radius and length of curve, baricentre positions, velocity, bearing friction etc. (enough said I think!).

 

I've found that there is also a variation in the 'rollabiility' of rolling stock. On my layout My Bristol Castle would handle seven WR chocolate and cream livery SD6* coaches without slipping, but only 6 maroon ones. It must be that some axles/bearings are smoother than others though they look identical. I had a very stiff full brake that replacement nylon wheels changed very little. Four sets of 3 rail metal wheels were the answer. The best wheels I have found are Nucro HD standard (better profile), but unfortunately are very hard to find these days. The real answer is pinpoint axles (I've fitted a WELTROL with success), but non standard axles are required (really a lathe job) and it destroys the originality of the vehicle.

 

The 20 coach train is interesting but I'm sure I've seen more from the same source. I'm sure there were LNER vehicles in the train. (These are lighter and don't count - I had my 'Gresley' pulling ten of them once.) The lead sheet is cheating of course and the ammeter shows she's quite close to her limit. All that weight on the bearings is not conducive to long life either.

 

* 'SD6' actually refers to the plastic wagons I think, but it is a convenient label for the later coaches.

 

When I bought my Dublo 'Barnstable', I tried her out on loose track on the floor (carpet!). I only had ten Dublo coaches to hand, but she just just romped away with that load. Must finish her restoration.... (I have got the thick overpaint off and the broken tender body has a new Wrenn   replacement. She goes backwards since converting to 3 rail, but I'm loathe to touch the motor.

Edited August 13, 2017 by Il Grifone

[Golden Fleece 30]

The maths for calculating the tip over point is quite complicated and involves vector diagrams and such like.... Factors involve radius and length of curve, baricentre positions, velocity, bearing friction etc. (enough said I think!).

 

I've found that there is also a variation in the 'rollabiility' of rolling stock. On my layout My Bristol Castle would handle seven WR chocolate and cream livery SD6* coaches without slipping, but only 6 maroon ones. It must be that some axles/bearings are smoother than others though they look identical. I had a very stiff full brake that replacement nylon wheels changed very little. Four sets of 3 rail metal wheels were the answer. The best wheels I have found are Nucro HD standard (better profile), but unfortunately are very hard to find these days. The real answer is pinpoint axles (I've fitted a WELTROL with success), but non standard axles are required (really a lathe job) and it destroys the originality of the vehicle.

 

The 20 coach train is interesting but I'm sure I've seen more from the same source. I'm sure there were LNER vehicles in the train. (These are lighter and don't count - I had my 'Gresley' pulling ten of them once.) The lead sheet is cheating of course and the ammeter shows she's quite close to her limit. All that weight on the bearings is not conducive to long life either.

 

* 'SD6' actually refers to the plastic wagons I think, but it is a convenient label for the later coaches.

 

When I bought my Dublo 'Barnstable', I tried her out on loose track on the floor (carpet!). I only had ten Dublo coaches to hand, but she just just romped away with that load. Must finish her restoration.... (I have got the thick overpaint off and the broken tender body has a new Wrenn replacement. She goes backwards since converting to 3 rail, but I'm loathe to touch the motor.

David, don't worry about stripping the motor to alter the magnet position just swap the brush wires over. All I do for converting Tri-ang locos was to move the insulating sleeve from one brush to the other.

 

Garry

[Killian keane]

Right, I'm just hoping you can make out the different colours on my crude diagram, I have based this on a tank engine with three bogie coaches for the sake of argument, the red vector is the loco, the resultant vector between the loco vector and the first coach is what propells the train because the former is a greater force, the resultant is shown in blue, it normally points straight forward on straight track, but angle alpha, {which represents a) the length of the vehicles in the train and b) how small the radius of the curve is}, causes the resultant to point inwards when the loco is pulling against the coaches and conversely causes the resultant to point outwards when the loco is pushing against the train, because each coach is essentially pulling the rest of the train, we have similar resultant vectors all along the train, but because the length of the train being pulled gets less as we go back along the train, the resistance vector gets less and so by the end of the train the resultant vector is negligable, this is why it is strongest at the front of the train, and only there will it have the sufficient magnitude to overturn the coaches, in short, if you must run long trains over tight bends, put the loco in the middle of the train

[sagaguy]

The maths for calculating the tip over point is quite complicated and involves vector diagrams and such like....  Factors involve radius and length of curve, baricentre positions, velocity, bearing friction etc. (enough said I think!).

 

I've found that there is also a variation in the 'rollabiility' of rolling stock. On my layout My Bristol Castle would handle seven WR chocolate and cream livery SD6* coaches without slipping, but only 6 maroon ones. It must be that some axles/bearings are smoother than others though they look identical. I had a very stiff full brake that replacement nylon wheels changed very little. Four sets of 3 rail metal wheels were the answer. The best wheels I have found are Nucro HD standard (better profile), but unfortunately are very hard to find these days. The real answer is pinpoint axles (I've fitted a WELTROL with success), but non standard axles are required (really a lathe job) and it destroys the originality of the vehicle.

 

The 20 coach train is interesting but I'm sure I've seen more from the same source. I'm sure there were LNER vehicles in the train. (These are lighter and don't count - I had my 'Gresley' pulling ten of them once.) The lead sheet is cheating of course and the ammeter shows she's quite close to her limit. All that weight on the bearings is not conducive to long life either.

 

* 'SD6' actually refers to the plastic wagons I think, but it is a convenient label for the later coaches.

 

When I bought my Dublo 'Barnstable', I tried her out on loose track on the floor (carpet!). I only had ten Dublo coaches to hand, but she just just romped away with that load. Must finish her restoration.... (I have got the thick overpaint off and the broken tender body has a new Wrenn   replacement. She goes backwards since converting to 3 rail, but I'm loathe to touch the motor.

 

Just rotate the magnet 180 degrees,ringfield magnets keep their magnetism,just make sure that you pull it out just enough to rotate it.

 

                                             Ray.

[Dunsignalling]

This is biggest problem I face, previous layout had 24" radius curves and I was lucky to get about 30 Hornby-dublo wagons round until they caved in on themselves, clearly there is some mathematical formula which takes into account factors like weight, resistance, of wagons plus camber, radius of curve etc. Some reason bogie stock such as coaches are more prone to derail.

 

Clearly pin point axles would help here is the dilemma, most of my pin point axle stock tend to also be very light, hence more likely to cave in on the curves, fact is Hornby Dublo stock stays on the track. What's more you can reverse such stock, try that with tension lock coupling light weight stock.

 

Still very interesting thread, about time that Australian record was broken, I think it's cheating a bit using 4 locos, I want to see what an off the shelf proprietary single locomotive in either HO or OO can do

 

As for rubber tyres, that was what was fitted by the manufacturer Triang Hornby some 47 years ago, the 9f evening star was I consider one of the best ever made in terms of pulling power and smooth running. It still has the original tyres on

I'm no mathematician by my instinct is that wagons are less prone to derail when attempting these stunts because the axles are spaced more evenly throughout the length of the train. Thus, whatever forces are involved should also be more evenly spread.

 

I shared your issue with the stability of modern r-t-r wagons and find that upping the weight by as little as 10-15 grams each improves matters no end. Unfortunately, that's also likely to reduce the number a loco can pull..............

 

The original Tri-ang-Hornby 9F with the outsourced brassy tender drive (made by either Fleischmann or Rivarossi IIRC) was a serious beast of burden, less so the later ones fitted with their own drive unit. 

 

Of modern loco-driven models, I reckon the Bachmann 9F tops the list followed (perhaps surprisingly) by Hornby's rebuilt West Countries and then their 8F. The proviso with all these, though is that they need a lot of running (15 to 20 hours, with gradually increasing loads) before they reach their peak ability. My best ones will pull almost 50% more than a brand new example of the same model. My theory is that you need to get the "newness" off the wheels to reduce slipping. 

 

John

Edited August 13, 2017 by Dunsignalling

[Dagworth]

I doubt those coaches are very heavy, sorry but if they are plastic it is not really that impressive when my Dorchester pulled all the heavy metal and glass built Exleys, it would have pulled these with ease, and more.

 

In 1962 a Hornby Dublo Deltic was demonstrated pulling 28 of their heavy super detailed coaches that were non pinpionted.

 

Garry

If you know the layout you will know that the whole train is on a gradient too, and it was from a standing start on the climb

 

Andi

[great central]

Many years ago now when I first joined the then Bulwell MRS we built a layout based on Bulwell Common on the GC including a curved representation of Bulwell viaduct around one end with the burrowing junction to Bestwood along the front. This meant that the main line had to rise as the branch fell away to allow the two to cross over under the viaduct.

At one show during silly hour on Sunday afternoon a competition arose between us and another, flat, layout to see who could run the longest train. People were moving between the two layouts, in separate rooms, watching the competition and telling us how many wagons the other layout was running.

We maxed out at 80 for my single Wrenn 8F, a mixture of Wrenn wagons towards the front of the train with lighter, then new, Mainline wagons making up the second half of the train. It took quite some driving skill as while the loco was climbing on one side of the layout wagons were running downhill on the other side and vice versa. Adding a second 8F allowed us to get to 100 just before the wagons stringlined across the curves which were, I think, in places less than 3ft radius.

Years later something similar was done on our Carstairs layout with a twin motored 90 (I think) which got to over 30 coaches if I recall correctly, that is a looped figure 8 layout with a long fairly steep climb off scene with a near on 2ft radius S bend at the top

Edited August 13, 2017 by great central

[Il Grifone]

David, don't worry about stripping the motor to alter the magnet position just swap the brush wires over. All I do for converting Tri-ang locos was to move the insulating sleeve from one brush to the other.

 

Garry

 

Hi Garry,

 

I seem to remember it's not as simple with the West Country as there's some sort of earthing tag and maybe one day I'll reconvert her to 2 rail (For now I just remember she goes the wrong way). Changing the Tri-ang sleeve is simple and I've done several this way though it's easy enough to reverse the magnet. My Lima 'Western' has the motor wiring reversed. She's a contender for the 100 wagon challenge and if anything is faster than my Tri-ang models, but has traction tyres of course.

[locomad]

Playing a lot last night various locos etc, Hornby Dublo deltic did manage 50 Hornby Dublo standard wagons before it shed another tyre, Hornby Dublo 8F managed 45 before it slipped like mad.

 

Another shot at pulling a large load was the Triang-Hornby Evening Star 9 F , this time 10 mins was given for a warm up (same for other locos), this seamed to make a big difference, it managed 60 standard Hornby Dublo wagons, in fact I ran out of stock hence loads of brake vans at back.

 

Resistance using a spring balance was 160 grams, at 12v amps was measured at .30 (unloaded .16), sound and noise was awesome, sweaking axles clanking wagons, to aid starting the loco backed up (like real thing) one and a half loco lenghts.

 

 

https://www.youtube.com/watch?v=MJYiJ4K_OX8

Edited August 13, 2017 by locomad

[Il Grifone]

My Dublo 8F suffers from slipping (she can 'only' manage 17/18 Dublo wagons*). Probably this is a legacy from her conversion to 2 rail back in the sixties. She had two driving wheels replaced (economy, though they are genuine Dublo wheels - 1/6d each IIRC) and the flangeless ones insulated with chrome tape (seemed like a good idea at the time 3/- was 3/-!). The combination of zinc alloy and nickel plate probably upsets her grip.

 

* Equivalent to 60 pin point wagons and probably all the prototype would have been allowed? (It wouldn't be all she could pull, but probably all she could stop!).

[34theletterbetweenB&D]

...Of modern loco-driven models, I reckon the Bachmann 9F tops the list followed (perhaps surprisingly) by Hornby's rebuilt West Countries and then their 8F. The proviso with all these, though is that they need a lot of running (15 to 20 hours, with gradually increasing loads) before they reach their peak ability. My best ones will pull almost 50% more than a brand new example of the same model. My theory is that you need to get the "newness" off the wheels to reduce slipping...

Getting the driven wheel tyres properly polished up ( I would imagine by removing manufacturing residues) by running is a real effect: this also applies to the rails. New track is less grippy than well used. 

 

Primary factor is always weight on the driven wheels. Of currently sold RTR OO loco drive steam models with no traction tyres, the Bachmann 9F is highly effective, second place goes to the Heljan O2. (The Hattons/Heljan Garratt now I think only available S/H will do more than either, if both motors keep running.) None of these are as effective as the RTR centre motor twin bogie models, some of which weigh in excess of 600g and all of it - or nearly all - on driven wheels in two subchassis. Quite apart from being heavier than steam models, this gives them a degree of immunity to loss of adhesion on features like pointwork and gradient transitions.

 

The first such on the UK market was Bach's 'Peak' back in 1992, and this item was immediately on introduction the best RTR OO loco for traction, not dependent on traction tyres. (I was outdoors at the time, and traction tyres had proved useless in this environment, weight was required, lots of weight.)

[locomad]

I'm no mathematician by my instinct is that wagons are less prone to derail when attempting these stunts because the axles are spaced more evenly throughout the length of the train. Thus, whatever forces are involved should also be more evenly spread.

 

I shared your issue with the stability of modern r-t-r wagons and find that upping the weight by as little as 10-15 grams each improves matters no end. Unfortunately, that's also likely to reduce the number a loco can pull..............

 

The original Tri-ang-Hornby 9F with the outsourced brassy tender drive (made by either Fleischmann or Rivarossi IIRC) was a serious beast of burden, less so the later ones fitted with their own drive unit. 

 

Of modern loco-driven models, I reckon the Bachmann 9F tops the list followed (perhaps surprisingly) by Hornby's rebuilt West Countries and then their 8F. The proviso with all these, though is that they need a lot of running (15 to 20 hours, with gradually increasing loads) before they reach their peak ability. My best ones will pull almost 50% more than a brand new example of the same model. My theory is that you need to get the "newness" off the wheels to reduce slipping. 

 

John

Quite agree running in new locomotives came as a surprise to us, having been brought up to "run in" older makes like Hornby dublo, I didn't expect to on modern makes,,however I too have noticed the older say 10 year old "modern" run better over time. Same applies to second hand older locos quite a few I believe have never been used just left in the box, I've had one which was described as "mint" which was almost solid.

 

The orginial traing Hornby Evening Star is a real beast, I've read it was and early 1960's design motor, its tender drive is well balanced and weighted, reckon grip is down to the clear neoprene traction tyres which on my model are the original ones.

 

I've not really tested modern ones since I have noticed the weak link is the tension lock coupling, I've ripped out one or two pulling long trains, same happens to some wagons in the train

 

Interesting this theory that the wheels needs the newness taken off, is it due to sparking? causeing very small pitting on the wheel, same applies to track, most of mine is over 40 years old and had lots of peco rubbers rubbing up and down over the years causeing slight scratches making the track a bit gritty.

[locomad]

My Dublo 8F suffers from slipping (she can 'only' manage 17/18 Dublo wagons*). Probably this is a legacy from her conversion to 2 rail back in the sixties. She had two driving wheels replaced (economy, though they are genuine Dublo wheels - 1/6d each IIRC) and the flangeless ones insulated with chrome tape (seemed like a good idea at the time 3/- was 3/-!). The combination of zinc alloy and nickel plate probably upsets her grip.

 

* Equivalent to 60 pin point wagons and probably all the prototype would have been allowed? (It wouldn't be all she could pull, but probably all she could stop!).

 

Since experimenting with these large trains I seemed to have learnt quite a bit about the haulage capacity of model locos what has surprised is the vast difference between locos of the same type.

 

Take the Hornby Dublo 8F I've a wrenn one chrome wheels it slips with about 27 HD wagons, an older HD 8F half inch motor managers 40, a converted 3rail to 2 rail one with scale wheels can haul 46 without slipping.

 

So all have the same weight body, perhaps the ring field motor up sets the balance, chrome plated wheels cause more slip.

 

Going over to 3 rail, steel track, mostly metal wheels on stock, on the whole the locomotives perform better on a temporary track laid on carpet I got one 3 rail 8F with carefully driving to manage 45.

 

So it's not just about power of motor, weight, but also slip, balance, running in, warmed up engines.

 

A real challenge would be one locomotive pulling 100 HD wagons non pin point

[Golden Fleece 30]

Since experimenting with these large trains I seemed to have learnt quite a bit about the haulage capacity of model locos what has surprised is the vast difference between locos of the same type.

 

Take the Hornby Dublo 8F I've a wrenn one chrome wheels it slips with about 27 HD wagons, an older HD 8F half inch motor managers 40, a converted 3rail to 2 rail one with scale wheels can haul 46 without slipping.

 

So all have the same weight body, perhaps the ring field motor up sets the balance, chrome plated wheels cause more slip.

 

Going over to 3 rail, steel track, mostly metal wheels on stock, on the whole the locomotives perform better on a temporary track laid on carpet I got one 3 rail 8F with carefully driving to manage 45.

 

So it's not just about power of motor, weight, but also slip, balance, running in, warmed up engines.

 

A real challenge would be one locomotive pulling 100 HD wagons non pin point

It has been a proven point that with Hornby Dublo the old 3-rail mazak wheeled locos pulled better than their equivalent 3-rail nickel wheeled ones, you do have to compare 8F's and Castles with like for like motors though.  Also I found that old Tri-ang locos with sintered iron tyres pulls better than when it was reintroduced with plated wheels.

 

Plated wheels were far better for electrical conductivity but not for pulling.

 

Track wise steel always had more "grip" than nickel but obviously corrodes but again was good for electrical conductivity.

 

I am not comparing Tri-ang's Magnadhesion on steel against nickel track as I remove the magnets due to them pulling against the wheels slightly.

 

Garry

[locomad]

It has been a proven point that with Hornby Dublo the old 3-rail mazak wheeled locos pulled better than their equivalent 3-rail nickel wheeled ones, you do have to compare 8F's and Castles with like for like motors though.  Also I found that old Tri-ang locos with sintered iron tyres pulls better than when it was reintroduced with plated wheels.

 

Plated wheels were far better for electrical conductivity but not for pulling.

 

Track wise steel always had more "grip" than nickel but obviously corrodes but again was good for electrical conductivity.

 

I am not comparing Tri-ang's Magnadhesion on steel against nickel track as I remove the magnets due to them pulling against the wheels slightly.

 

Garry

 

Thanks very interesting, I have always believed the 3 rail locos pulled more because on the whole they pull 3 rail stock fitted with metal wheels which I believe have less rolling resistance. I also test stock on an adjustable incline, some well oiled 3 rail stock will roll on a 1:45, while 2 rail plastic your luckily to get 1:35, while quite a few fail at 1:30.

 

Triang stock especially old iron wheels seem to get better with age, most of mine are fitted under old wills white metal kits, some quite easy out perform similar Hornby dublo stock, course nearly all now have had the wheels pulled out a bit so back to back measurement fits later peco point frogs

[Il Grifone]

The Deltic demonstration was 51 wagons and non-stop for 100 real miles at a scale speed of 86mph. Since the wagons were standard Dublo this is well in excess of the required 100 wagons if fitted with pin point axles.

 

The young lady weighed 8 stone and required three Deltics. It is not stated whether the trolley had ball bearings or not. This is around 600 ounces each, so again well over 100 wagons.

 

Perhaps someone would like to try. My oval test track only has space for about 30 wagons, but most locomotives do not have problems with this many. Pin point axles and mainly Airfix 16 ton minerals weighted to about an ounce. 15¾" radius curves (Trix fibre) add to the drag....

 

Dublo vehicles are supposed to start to roll on a 1 in 30 gradient. Most will, but I have met the odd stubborn case. 1 in 100 is not asking too much of pin point bearings.

Edited August 16, 2017 by Il Grifone

[Golden Fleece 30]

Thanks very interesting, I have always believed the 3 rail locos pulled more because on the whole they pull 3 rail stock fitted with metal wheels which I believe have less rolling resistance. I also test stock on an adjustable incline, some well oiled 3 rail stock will roll on a 1:45, while 2 rail plastic your luckily to get 1:35, while quite a few fail at 1:30.

 

Triang stock especially old iron wheels seem to get better with age, most of mine are fitted under old wills white metal kits, some quite easy out perform similar Hornby dublo stock, course nearly all now have had the wheels pulled out a bit so back to back measurement fits later peco point frogs

I actually machine a little off the backs to allow Tri-ang wheels to go though modern universal Peco points (which are finer than the old universal types).  Even the old solid wheels are happy with the new track.  Pushing the wheels out was a non starter for me as I still use set track curves and the wheels would then become tight due to he flanges further apart.

 

Garry

[Il Grifone]

My attempts at turning down Dublo wheels (some idea about converting a 2-6-4T to EM) were of mixed success. One was good and one overcooked!. 'New' wheels from eBay solved that.... (about 20 years later!)

Edited August 16, 2017 by Il Grifone

[Joseph_Pestell]

As one gets to larger scales, this should be more difficult. But Beckenham & West Wickham MRC regularly ran 115 wagon trains on their 0 gauge Kelsey Park layout. That included an up-and-over figure of eight. I think the loco could have handled more but, even with a large layout, the loco was not that far behind the brake van on the continuous run.

 

Following up a theory above, Kelsey Park was also (outside) 3rd rail electric.

[locomad]

 

Perhaps someone would like to try. My oval test track only has space for about 30 wagons, but most locomotives do not have problems with this many. Pin point axles and mainly Airfix 16 ton minerals weighted to about an ounce. 15¾" radius curves (Trix fibre) add to the drag....

 

Dublo vehicles are supposed to start to roll on a 1 in 30 gradient. Most will, but I have met the odd stubborn case. 1 in 100 is not asking too much of pin point bearings.

I've borrowed some extra stock mainly modern pin point problem seems to be getting them round the track, on the straight if I had a long enough one would be no problem.

 

Problems I'am coming across,

 

Falling in on themselves, Hornby Dublo stock sticks to the track round curves, despite some extra weight modern stock seems to be more prone to falling in as forces applied this have been discussed before, we are talking here of in excess of 80 wagons. A train of all day 50 HD no problems, but 50 modern wagons often pull on on themselves, it could be down to locking of tension coupling, something which does not effect peco ones.

 

Engine starting, over 50 wagons the locomotives are reversed untill the brake van moves, just like real thing, so the locomotive starting does not take the whole load, again easy to back up stock with peco, not so with tension lock which often derail backwards

 

Some success mixing the stock, HD directly behind the locomotive, pin point at the back, I'am up to 80 at the moment it's getting the mix right and sorting out unreliable wagons which cause derailments there's seem to be a lot of modern stuff which can't cope

[Joseph_Pestell]

I've borrowed some extra stock mainly modern pin point problem seems to be getting them round the track, on the straight if I had a long enough one would be no problem.

 

Problems I'am coming across,

 

Falling in on themselves, Hornby Dublo stock sticks to the track round curves, despite some extra weight modern stock seems to be more prone to falling in as forces applied this have been discussed before, we are talking here of in excess of 80 wagons. A train of all day 50 HD no problems, but 50 modern wagons often pull on on themselves, it could be down to locking of tension coupling, something which does not effect peco ones.

 

Engine starting, over 50 wagons the locomotives are reversed untill the brake van moves, just like real thing, so the locomotive starting does not take the whole load, again easy to back up stock with peco, not so with tension lock which often derail backwards

 

Some success mixing the stock, HD directly behind the locomotive, pin point at the back, I'am up to 80 at the moment it's getting the mix right and sorting out unreliable wagons which cause derailments there's seem to be a lot of modern stuff which can't cope

The older stuff mostly have diecast chassis, so a much lower centre of gravity. That will be why they are less prone to falling over on curves.

[locomad]

The older stuff mostly have diecast chassis, so a much lower centre of gravity. That will be why they are less prone to falling over on curves.

Quite agree, the ideal stock would be the older type wrenn wagons diecast chassis, pin point axle very free running, unfortunately I've very few as the tension lock coupling was introduced, however some kept the old peco mounting coupling which I converted too many years ago. They also make good converter wagons.

 

Good example of higher center of gravity is the old triang tiewag car transporter, I've a set of 8, empty no problem, load them with heavy Oxford diecast cars and they collapse quite spectacularly found a curve.

 

Lead sheet on light stock laid on the floor is one solution

[Il Grifone]

Most modern stock is plastic and has a strip of steel under the floor, so the baricentre will only be fractionally higher than a Dublo of Wrenn wagon. It could even be lower in the case of metal wheels on the former and plastic on the latter.

 

The standard tension lock pulls through the outer hook on curves, which will then tend to slide inwards along the bar pulling the vehicles skew. Not normally a problem, this could tend to cause derailments under high loading.

 

The Tri-ang car transporter was intended to be loaded with Minix cars which, being almost all plastic, weigh very little. (IIRC only the axles are metal.)

 

http://www.tri-ang.co.uk/indexminix.htm

 

Oxford cars are rather better models (though painting the Minix improves them considerably), but are rather heavy in scale terms. 1 tonne (roughly the weight of a car) divided by 76.2 cubed comes out to 2.25 grams (ignoring a lot of decimals...)

Edited August 18, 2017 by Il Grifone

[locomad]

We maxed out at 80 for my single Wrenn 8F, a mixture of Wrenn wagons towards the front of the train with lighter, then new, Mainline wagons making up the second half of the train. It took quite some driving skill as while the loco was climbing on one side of the layout wagons were running downhill on the other side and vice versa. Adding a second 8F allowed us to get to 100 just before the wagons stringlined across the curves which were, I think, in places less than 3ft radius.

Years later something similar was done on our Carstairs layout with a twin motored 90 (I think) which got to over 30 coaches if I recall correctly, that is a looped figure 8 layout with a long fairly steep climb off scene with a near on 2ft radius S bend at the top

 

Very interesting, this is what I discovered over the weekend, there is a direct link between the length of train and the radius which limits the length of train before the wagons collapse inwards on them selves.

 

This time HD, 8F 1/2 motor pulling 30 HD wagons and a mixed bag of pin point axle stock at the back, managed 83 wagons before, on the curve, the wagons next to the loco collapsed on themselves.

 

Same happens when other locos tried often double headed, took a few wagons off the train got round at about 80-83 same thing happened time and time again.

 

I also noticed the drag or resistance of pin point axle trains greatly increased when long trains went round curves, this say a 30 wagon train on the straight some weaker locos could easy manage it, until the curves when they slipped or just stopped.

 

On a 50 wagon train using a spring balance it almost doubles the resistance, while only a slight increase using non pin point axles. So the advantage is almost lost using pin point axles, I suspect it's due to the forces involved on the axle pushing inwards increasing resistance.

 

So for now I don't thing on my existing layout it's possible to pull 100 wagons while the average radius is 30" it limit is about 80 wagons