The two biggest drawbacks of the Leader barely get a mention from the Narrator: The Fireman's Cab was in the middle of the locomotive and was virtually totally enclosed ... this resulted in the poor Fireman being effectively roasted alive as soon as the locomotive went out on the road, especially as the firebox also had a tendency to shoot flames out of the firebox door! The other problem stemmed from a drawback that Bulleid recognised early in the design stage ... there was no effective means of communication between the Driver and the Fireman. This he tried to rectify by including an internal walkway between the Driver's Cab and the Fireman's Cab ... but the only way this could be done was by offsetting the boiler to one side, as can be seen in the end elevation of the line drawing at 0:23. Unfortunately, due to the considerable weight of the boiler being more to one side of the locomotive than the other, this resulted in excessive wear of the bearings, axle-boxes, cranks and running gear on one side of the engine and led to endless mechanical failures when the locomotive was under trial. In many ways, Bulleid was a great innovator and was always keen to try out new ideas ... unfortunately most of them came to nought due to the limits of the technology of the time and the fact that steam was nearing the end of it's era anyway.
@@sockshandle Yes ... I was around at the time! But the writing was on the wall ... it did take a long time to sort out the the most suitable replacements though! Some would argue what was the point in continuing to build steam locomotives throughout the 1950s and even in 1960, but the reality is that diesels of the time were simply not up to the levels of power and reliability that steam could still provide.
@@jwalster9412 the obvious fix would have been to switch to Oil firing of the boiler... well ironically the design was actually intended to be Oil fired in the first place and had to be adapted to use coal. The British Government had actually pushed for the design to use oil to make up for shortages of coal. All very well during wartime Britain when the UK was getting oil from the US for effectively free but with the end of WWII the cost of imported oil shot up making it uneconomic to run a locomotive using it and forcing the design team to switch to coal firing. That being said feeding the coal to the firebox using some form of screw would have been a perfectly valid alternative, actually it was a very mature technology and called a 'Mechanical stoker'. They were common in Europe and the United States but not the UK. Curiously Southern Railway even trialled a Canadian made Berkley mechanical stoker on one of their Merchant Navy Class locomotive. They rejected it as not offering that much of a performance improvement, why they didn't think about trying it with the Leader is a puzzle to me!
3:53 "For ease of maintenance, the boiler, firebox and smokebox were encased in steel sheeting." That's the exact opposite of "ease of maintenance" which is why so many streamlined steam locomotives through history had their streamlining removed...
The main test engine had a damaged power bogey which was bent while being tested on a stationary rig at the shop when a manager threw it into reverse while it was at speed. They refused to change it out when it became unreliable so it seems they wanted it to fail. I only know this because a good friend of mine was a draughtsman at the brighton shop while the Leader was being built.
Proverb (probably American) 'I learn so much from mistakes that I really should make some more of them' Look out for an amazing YT vid of the Leader semi rotating axial sleeve valves. It is amazing that the draughtsmen of the day could visualise their components and how they would work together.
It is sad that it was scrapped. As also for GT1 Even failures have provided knowledge and experience. To lose sight of that is to lose sight of the process of development. Which makes us, as a community, move to stagnation. Little was gained by scrapping but plenty is able to be gained by keeping examples available for whatever a future might hold.
Who else wants to see one of these resurrected and on the mainline? That would be nice. Maybe on the Golden Arrow taking it in turns with Clan Line and there could be a double header of the two!
I think they should make a steam one BUT a lot of work would have to be done because I think if one did, they’d have to do major modifications to make it actually decent; because if it wasn’t upgraded, there’d be no point as the leaders weren’t exactly… Good.
".... sadly this was not the case." I can't agree when I consider the "untenable working conditions" for the crew and the heavy coal consumption mentioned. The truth is that steam was outdated for the post-coal era and there was more consideration being given to workers' health and safety. And, I'm old enough to remember the smog in London, first-hand as a child. Despite my loving steam locos and the history of them, it was the smoke of domestic chimneys, and the railways, which combined with thick fogs off the Thames, that caused smog.
@@gordonphillips7229 Yes indeed. I used to live almost opposite it, on a houseboat at the Lot's Road end of Cheyne Walk - how could I have forgotten? :)
@@brando6BL Probably because those chimneys stacks were so tall and therefore less polluting compared to those of locomotives and houses, and maybe of your houseboat too!
Oliver Bulleid was CME at CIE Ireland after his days at Southern. He designed a Locomotive similar in design to the leader,it was known as the turf burner turf being used to fuel it.
On the Southern, Bulleid took an H2 Atlantic and altered its cylinders to test the sleeve valves, not enhancing its appearance. I believe he modified a loco on CIE as well.
Great video. Like you said the Leader had more than a few issues. The fireman was in a horrifically confined area with poor ventilation which lead to the temperature being unbearable to work in.
Vector Brony not only that if the loco rolled over it was 50-50 that he'd have an escape route as only only one cab door was fitted. The communication corridor along side the off-set boiler, which caused some of the uneven bogie loading, was filled with scrap rail to balance up the bogie loading caused by the off-set boiler. The driver either was hot or cold depending on which cab he was in, nor could he talk to his fireman whilst driving breaking up sense of being part of a team.
Perhaps the 'root' of the problem was that the locomotive was originally intended for oil firing, which would not have required the dotty offset boiler (and multiple tons of scrap metal used as counterweighting) or confinement of fireman in hot space made hotter during blowback in tunnels. (Oil had to be imported, from countries typically using dollars instead of pounds for exchange, which is why Britain paid such attention to coal-burning standards up through Riddles' standard classes) Likewise there were supposed to be two sets of chains on either side of the drivers on each bogie (chains drove the leading and trailing axles) but only one side was fitted. This was of more than usual importance because of the design of the suspension; the offset loading causing increased binding and other issues. I am not sure I would consider the valves in the Paget locomotive to be similar to the arrangement on Leader, which used Meehanite sliding sleeves with a great many ... too many! ... sealing rings for its great plurality of ports. Theoretically this gave an utter minimum of dead space for enormous port opening, the problem being that oiling arrangements were correspondingly very complex and even partial failure of one of the many oil lines would cause accelerated wear, ring breakage, or seizure. The rather fascinating 'figure-8' motion in the original valve drive was intended to keep the sleeves turning slightly radially at the same time they were being moved fore-and-aft for actual valve action, but this wasn't intended as a Willoteaux-like acceleration of effective porting/unporting or, in fact, any kind of rotary valve action a la Paget. I personally think that the tests on Hartland Point (which you should mention here, even if briefly) should have caught all the problems early enough to work out fixes (or determine, perhaps a more likely outcome, that the theoretical gains in dead-space reduction and other concerns relating to poppet-valve or other alternative valve arrangements like Cossart 'drop valves' weren't worth all the problems of keeping all those rings unbroken and steam-tight)
Good video, but a project deserving harsh criticism. An example of very poor engineering management. To say that 'if successful it would have prolonged the life of steam' - what features did Leader have that would have accomplished this? Steam was prolonged on BR, by nearly 20 years, based on proven designs. I think it it unclear how the problems that were being addressed neccesitated that design. For example, if a double cab is a solution, there's a way of introducing that feature without some of the other ambitious features that didn't work, and perhaps getting a working loco. To have ordered and started 5 'off plan' without testing even one was a serious error.
Such a pity..that today with all the technology available we can't produce an effective steam powered engine....that would compete with electric ones. Thank you for this interesting video.. 👍👍👍
Wow, weird! Nearly a good idea, some lateral thinking on display but I imagine the amount of preparation before the off in the morning was enough by itself to give diesel and electric trains the edge in operating convenience over steam by then.
As soon as WW2 was over and we were back in peacetime, the government should have been looking at Diesel, and Electric locos to replace steam. That we didn't do this, and it didn't even cross our minds to speaks volumes. I've nothing against steam, or steam trains, but we were still building new ones into the 60's! This steam train does indeed look like a tube train! But what on earth were they doing?? Why weren't they thinking Diesel and/or Electric!?? Mind boggles....
They were. The Dieselisation plan came about in the early 1950’s, and the last steam loco was built in 1960. Pre-grouping railways were already on to electrification, the big 4 all already had a plethora of diesels, and BR ordered the first ones in the 1940s.
This is an interesting and watchable video. Thank you! Do I assume that, as far as we know, there is no motion footage of this locomotive upon (say) super 8?
The result of the 1955 Modernization Plan shows that even an unorthodox coal fired loco like Leader was not going to extend the life of steam. The flexible joints necessary to the design seem like a maintainer's nightmare. Bullied should at least have put the driving wheels in the center of his loco so the power unit was one piece. The Southern Pacific cab forward designs were more successful but they were all fueled by easy to handle fuel oil, not coal.
@@billcobbett9259 So the "modernity" didn't extend to a mechanical stoker, and a steam turbine driving an electric generator powering the wheels (all known technology since 1884), just the same old. It is interesting that for all the innovations in steam locomotive design since Locomotion 1 (1825) to Evening Star (1960) the steam locomotive stayed in the same configuration with pistons, valve gear and a driver and fireman working behind a boiler, with the fireman shovelling coal from a coal box behind him. Rubbish ergonomics for both operating and maintenance. "This is the way it's always been done lad, no need to change".....
@@SuperNevile the LMS did build a one-off turbine version of the Princess Royal class. Nicknamed the "Turbomotive", it was unfortunately damaged in an accident, and then rebuilt as a standard pistons-and-valve gear loco.
@@alanclarke4646 It’s interesting that experiments were carried out on various forms of rail traction, but the industry stayed mainly with steam technology developed in the early 19th century. Electric (catinary type) locos operated out of Shildon in the early 20th century, and they were toying with diesel electric, but didn’t go further. The underground went electric (for obvious reasons) early 20th century. But when the aviation industry went from the Wright Flyer to Concorde in under 64 years, the inclination not to go to more efficient, more ergonomic (and cleaner) rail locomotion is striking even with the massive coal industry available.
I think if the UK had followed America's ACE 3000 Project (Which sadly wasn't funded enough apparently) Maybe something like this would have worked out in the long run.
That's an often misunderstood phrase about the Leader. It had the same route availability as an M7 (similar axle weights) but wasn't built to directly replace the M7.
I feel like the powered chain bogies could've been put to good use regardless, as possibly for some self-driving breakdown cranes, or even self-driving railway artillery cannons, for example.
I doubt that even if the Leader had been sucessful that steam would have lasted much longer than it did. It was the economic conditions in the country that put pay to steam, starting just after WW1 with the introduction of reliable diesel shunters. Gresley's EM1 and Ivatts 10000/10001 were the true leaders.
Well, in his partial defense, he did adapt the design considerably in the 'turf burner' including the substitution of more-or-less conventional piston valves for the sleeve valve arrangement, and fixing the other issues with the bogie design. And interestingly, it appears that the boiler, strange as it looked, was actually effective in making reasonable power from the low-grade fuel. The real reason it 'failed' was less technical than economic: instead of a relatively large and complicated arrangement to burn native fuel, it made better economic sense to use relatively fuel-efficient diesels (whose development cost and parts availability could be shared with other owners)
@@wizlish i suppose but with the turf burner, instead of doing what i thought he would do which is having a cab either end where you could drive it from both sides but only fire it from one end (or make it possible to have two fireboxes), he put both the fireman and driver into a cupboard where all the controlls were. This limited visability and imagine how hot it must have been. Youd better hope he made AC a feature with his steam generator because if he didnt i think most crews would have been cooked before reaching cork. (They were meant for dublin - cork expresses.)
@@Spud607 - This had me chuckling while thinking about the New Zealand E1066 for the Spiral - another somewhat roasty design. But actually there was care taken with additional fiberglass insulation in the backhead and plenum areas of the boiler, and I don't recall heat in the cab area being notably higher than that of a conventional boiler (and certainly a dry-back firebox like the one installed on Leader!) Remember that none of the contemporary designs (bogie or otherwise!) worked with double-end driving -- they would all involve crew separation or complicated fuel arrangements. If you have oil or pulverized-fuel firing, there is no particular problem in having both crew in an end-cab (see the German 4-6-4 05 003 as built) but the firing provided for the Turf Burner (or a logical alternative chain-grate like the version used in the N&W TE-1) would still require a complicated feed path in the absence of full automatic control (which was not practical even in the latter '50s with Bailey Meter controls derived from nuclear submarine control experience, let alone with cost-effective technology in contemporary Ireland). So the logical thing is to use the time-honored layout for large bogie-borne steam in the United States, with a center cab between bunker and boiler, and rig the locomotive for effective bidirectional control with 'one man per side' making up for the restricted vision. Of course, even then the television system used for CASTOR was practical as a means of seeing what was ahead, and would be a preferred approach technically if the locomotive were to be replicated today... The thing that most people seem to be forgetting is that the Turf Burner was not a technical failure -- it was just not seen as being as economical as even the pathetic diesels provided to CIE by the early '60s. (Which, it can't be argued with much enthusiasm, it really wasn't...)
so technically this should have just undergone a diesel retrofit and it might then have been more worth while. seeing this class of loco on KR Models and how interesting it looks made look up on how rare it was because KR models have doen some rare loco's so far
59/66 is same but the difference is the details and the sounds. Class 59 where built in 1985 was a prototype of Class 66 where built in 1998, Class 59 has more power than Class 66.
I wish one of these had made it into preservation. Massive loss just like his CC electrics. If he'd ditched the sleeve valves and used a more conventional valve gear it might have worked. Unfortunately, nationalisation and the LMS got in the way.
I think automotive-type poppet valves were the coming thing at the very end of steam engine technology. Sentinels used them for their lorries. They provide a much better gas seal.
You only have to watch the youtube video of the rotating, oscillating sleeve valves moving in three dimensions to realise the whole thing was just too complex for its own good. It needed a better design as the orignal would have been a nightmare to maintain and set up at a depot.
The fireman was in the middle of the loco while the driver (obviously) was in an end cab. So there was not the level of co-operation that was normally possible. As with many forward-looking projects, too many new features were piled in at one go, so the weakest link discredited all of them, unfortunately.
When something rare is in preservation its usually because of its historical value, not wether it looks good or not, especially in this case with only one being built.
You can't just preserve the 'nice things'. That would make for dull museums with an incomplete history. The leader was an intersting engine technologically. it also marks an attempt to make steam compete with diesel and electric locos. Though it never would have. I do wish it had been set aside but BR were never good at preserving protoypes (but back then no-one was). P.S. Its not a pretty machine but I do kinda like how it looks. Its a beast.
@@chrishartley4553 If lt had been preserved, then the steel sheeting should have been thrown out. Then all the innovative parts could have been exposed.....the valve gear.
It needs someone to to build one today using modern manufacturing methods, plus getting rid of the ridiculous idea of having a corridor running between the fireman’s footplate and the driving cab in front of the smoke box which meant the boiler was offset, so causing weight distribution problems, having an the footplate accessible from both sides of the loco, so the fireman had more light and air, then it would work. The basic principles were right but the manufacturing and execution of the project was all wrong.
Oops, my mistake: I thought this was the US Southern Railway, not British Rail. This was an interesting steam locomotive concept/design, however. I did enjoy the video.
If only there were 00 gauge models of at least one of every one that ever existed of every class of everything British railway related of every steam, diesel, electric, DMUs, EMUs DEMUs etc freight etc, passenger, and maintenance etc rolling stock etc. Maybe Hornby in the next 100 years will have achieved this if Hornby legend Simon Kohler has his way I think we will!
Very interesting and a real shame about the problems. The missed opportunity was to fire it on DIESEL so a comparison of efficiencies and flexibility between the IC engine and the EC engine. With stored steam pressure of the EC engine, It could well have accelerated better than the IC engine - and with boiler development and a little automation, not needed a fireman at all.
OIL-firing was used on steam locomotives during a government-backed initiative after the war, although on a limited basis. The LEADER project did, at one time, include the possibility of OIL firing; there is a reference to both crew members carrying out their tasks seated, which would imply oil, rather than coal, as fuel. DIESEL is a different technique altogether. It involves INTERNAL combustion, with the fire actually inside the cylinders, rather than in an EXTERNAL firebox heating a boiler. It has no relevance to the LEADER project whatsoever. The two should not be confused.
@@bingola45 "there is a reference to both crew members carrying out their tasks seated, which would imply oil, rather than coal, as fuel." Did we not achieve automated coal feed ? It seems the US did. How you burn diesel depends on the burner whether in a cylinder or not.
@@millomweb Mechanical stoking was tried on locomotives in Britain, but with little success. I've never come across any suggestion of using it on the Leader class, although it might have been possible. The Diesel engine is, by definition, an Internal Combustion oil engine. There was a type of stationary engine which combined both cycles, at opposite ends of a double-acting cylinder, called the Still system, AND a locomotive was produced by Kitson and Co. of Leeds, using this principle, and, unsurprisingly, called the Kitson-Still locomotive. You appear to have mistaken Diesel for a type of fuel oil. It isn't. It's a thermal cycle named for the engineer who patented it. The two should not be confused.
@@bingola45 "The Diesel engine is, by definition, an Internal Combustion oil engine" You've added 'engine' to that. I never said 'engine'. "You appear to have mistaken Diesel for a type of fuel oil." No mistake - diesel is a specific fuel oil for the purpose of fuelling Rodolph Diesel type engines. But that doesn't stop you spraying it as a mist through a nozzle and igniting that mist - as per heating oil - which isn't vastly different. AKA: DERV !As it's used as a fuel for DERVs.
@@bingola45 "Mechanical stoking was tried on locomotives in Britain, but with little success" What were the difficulties with it ? If you watch Keith Rucker on Vintage Machinery channel (based in Tifton, Georgia, US of A), He spends some of his spare time at an ag/mech museum and one 'little' job he's assigned himself to is to get a stoker engine back into working condition !
High power and low maintenance ..... sounds like SR needed an electric locomotive. If an engineering department is looking for ways to extend the life of steam traction, then by definition, it is at the end of its useful development. What made this locomotive look odd, was the bogie arrangement wasn't configured as a mirror image.
@@channelsixtysix066 The only thing 'weird' about it was that it used steam technology. Mainstream Diesel locomotives used this double-cab bogie layout almost exclusively.
@@likklej8 I can't remember much of my study of the *_Leaders_* but I recall that there were many design problems. One thing was the lubrication of the valve-gear and another was the water supply for the boiler which I think was by pump rather than injector. I think it had a faulty chain grate too.
Bullied would be Buleed. Bullied would be Bulleid. That’s the English I was taught in the forties/fifties. I do know he was always pronounced BULEED. ?
Unfortunately Jim English these days is not taught anywhere as precise as it was back then. Don't even get me started on the deteriorating spelling standards! Cheers mukka.
He overthought it. Instead of having steam powered wheels, he should have linked steam output to a generator and had six traction motors in a simpler bogie. Nice try, but no banana.
Colin Easton - the Swiss did this the other way round during the war and produced a few steam engines which took their (hydroelectrically generated) power from the OHLE to "fire" the boiler (think "kettle") and produce steam for the otherwise conventional engine.
They look quite a lot like Boxpok wheels indeed, but are slightly different. These "BFB"-wheels were also used on the SR Merchant Navy Class, the Battle of Britain class and the Q1 class - all Southern Railways, where Bulleid was CME.
Why would British Rail insist on holding the their railway into the steam era when Germany and America were aggressively dieselizing their railway? Doesn't make economic or operational sense from a labor cost standpoint.
@@peterudbjorg *Bulleid,* rather an autocrat, believed he could design a steam locomotive that didn't need the amount of labour that a conventional steam locomotive. He failed.
@@jackdripper5675 *Britain* got rid of steam locomotives much more quickly than was economical for political reasons. The politicians wanted _modernity_ in everything.
The country was skint after the war, and unlike Germany and Japan, had to maintain a sizable defence budget. Those countries were able to invest in public and commercial ventures that utilised their proven skills in technological innovation.
It seems that everything that deviates from the standard steam locomotive design, is not successful ( The French steam electric Heilman locomotives where a technical success but did founder on prejudice & trade union idiocies...) experiments with steam turbines, uniflow steam engines, exotic valve gears & high pressure steam just did not work... using chain drive for the drivewheels is asking for trouble, and what about the valve gear ? Was nothing better available ?
@@georgewindsor6438 The 'point of articulation' is the apparent point around which something pivoted appears to turn. An articulated lorry is a good example. Nothing actually 'bends'; the tractor and trailer are so constructed that the overall wheelbase is not rigid. This is called 'articulation'.
The two biggest drawbacks of the Leader barely get a mention from the Narrator:
The Fireman's Cab was in the middle of the locomotive and was virtually totally enclosed ... this resulted in the poor Fireman being effectively roasted alive as soon as the locomotive went out on the road, especially as the firebox also had a tendency to shoot flames out of the firebox door!
The other problem stemmed from a drawback that Bulleid recognised early in the design stage ... there was no effective means of communication between the Driver and the Fireman. This he tried to rectify by including an internal walkway between the Driver's Cab and the Fireman's Cab ... but the only way this could be done was by offsetting the boiler to one side, as can be seen in the end elevation of the line drawing at 0:23. Unfortunately, due to the considerable weight of the boiler being more to one side of the locomotive than the other, this resulted in excessive wear of the bearings, axle-boxes, cranks and running gear on one side of the engine and led to endless mechanical failures when the locomotive was under trial.
In many ways, Bulleid was a great innovator and was always keen to try out new ideas ... unfortunately most of them came to nought due to the limits of the technology of the time and the fact that steam was nearing the end of it's era anyway.
could have been fixed with a screw to bring coal into the firebox like other countries have done before, I wonder why they dident?
"Nearing the end of its era" Um you are aware that in a lot of areas steam was still in use post 1950s right?
@@sockshandle Yes ... I was around at the time! But the writing was on the wall ... it did take a long time to sort out the the most suitable replacements though! Some would argue what was the point in continuing to build steam locomotives throughout the 1950s and even in 1960, but the reality is that diesels of the time were simply not up to the levels of power and reliability that steam could still provide.
@@jwalster9412
Weight. It was already over it's intended weight.
@@jwalster9412 the obvious fix would have been to switch to Oil firing of the boiler... well ironically the design was actually intended to be Oil fired in the first place and had to be adapted to use coal. The British Government had actually pushed for the design to use oil to make up for shortages of coal. All very well during wartime Britain when the UK was getting oil from the US for effectively free but with the end of WWII the cost of imported oil shot up making it uneconomic to run a locomotive using it and forcing the design team to switch to coal firing.
That being said feeding the coal to the firebox using some form of screw would have been a perfectly valid alternative, actually it was a very mature technology and called a 'Mechanical stoker'. They were common in Europe and the United States but not the UK. Curiously Southern Railway even trialled a Canadian made Berkley mechanical stoker on one of their Merchant Navy Class locomotive. They rejected it as not offering that much of a performance improvement, why they didn't think about trying it with the Leader is a puzzle to me!
3:53 "For ease of maintenance, the boiler, firebox and smokebox were encased in steel sheeting." That's the exact opposite of "ease of maintenance" which is why so many streamlined steam locomotives through history had their streamlining removed...
True, that statement took me aback. I think the narrator is just referring to washing it.
Minus the A4s,they were the only locos that didn't got their streamlining casing removed
@@davidantoniocamposbarros7528 Even the A4s had the valences over the wheels removed -- for... you guessed it... ease of maintenance!
This even happens in Star Wars with the rebel fleet ships lol
I read that the sheeting was designed to go through washing plants just like carriages.
It looks like a swole London Underground train.
Yes
That's what i thought too
Yes - I thought that exactly. I am sure there is some subtle connection there!
As the body shape looks like a Deep level tube train.
The main test engine had a damaged power bogey which was bent while being tested on a stationary rig at the shop when a manager threw it into reverse while it was at speed. They refused to change it out when it became unreliable so it seems they wanted it to fail. I only know this because a good friend of mine was a draughtsman at the brighton shop while the Leader was being built.
Proverb (probably American) 'I learn so much from mistakes that I really should make some more of them'
Look out for an amazing YT vid of the Leader semi rotating axial sleeve valves. It is amazing that the draughtsmen of the day could visualise their components and how they would work together.
The leader has always been one of my favourite railway oddities! Not been able to find much info on it since now, very enjoyable video :)
Thanks very much
It is sad that it was scrapped. As also for GT1 Even failures have provided knowledge and experience. To lose sight of that is to lose sight of the process of development. Which makes us, as a community, move to stagnation. Little was gained by scrapping but plenty is able to be gained by keeping examples available for whatever a future might hold.
Who else wants to see one of these resurrected and on the mainline? That would be nice. Maybe on the Golden Arrow taking it in turns with Clan Line and there could be a double header of the two!
maybe oil-fired? That would be a fun project
Man, I’ve had so many day dreams of making an oil fired one of these!
Put my name down to see an oil- fired one.
I think they should make a steam one BUT a lot of work would have to be done because I think if one did, they’d have to do major modifications to make it actually decent; because if it wasn’t upgraded, there’d be no point as the leaders weren’t exactly… Good.
It looks more like a monster truck crossed with a tube train
I note that the boiler was the least of the problems (save high coal usage) The one good thing that Mr Bull Lied was good at was boiler design.
The interesting thing is this is a steam loco that looks like a diesel loco.And people say we were dumb
TBH you all made a great video
Reminds me of the Class 59s.
Agnetha and Frida are the best...!
it does have quite a similar resemblance to many british diesel locomotives that have 6 driving axles and the same body design with the flat ends
".... sadly this was not the case."
I can't agree when I consider the "untenable working conditions" for the crew and the heavy coal consumption mentioned. The truth is that steam was outdated for the post-coal era and there was more consideration being given to workers' health and safety. And, I'm old enough to remember the smog in London, first-hand as a child. Despite my loving steam locos and the history of them, it was the smoke of domestic chimneys, and the railways, which combined with thick fogs off the Thames, that caused smog.
Not to mention Battersea Power Station!
@@gordonphillips7229 Yes indeed. I used to live almost opposite it, on a houseboat at the Lot's Road end of Cheyne Walk - how could I have forgotten? :)
@@brando6BL Probably because those chimneys stacks were so tall and therefore less polluting compared to those of locomotives and houses, and maybe of your houseboat too!
Son: Mom let’s get a diesel on the way back.
Mom: we have diesel at home.
Diesel at home:
Lol
Oliver Bulleid was CME at CIE Ireland after his days at Southern. He designed a Locomotive similar in design to the leader,it was known as the turf burner turf being used to fuel it.
On the Southern, Bulleid took an H2 Atlantic and altered its cylinders to test the sleeve valves, not enhancing its appearance. I believe he modified a loco on CIE as well.
On paper , a good idea, but didn't work in reality, poor driver and especially the fireman. Would have been nice to see 36001 preserved as a oddity!!!
an awesome account T3....best I've heard and learned a lot too. thanks for this!
Great video. Like you said the Leader had more than a few issues. The fireman was in a horrifically confined area with poor ventilation which lead to the temperature being unbearable to work in.
Thank you
Vector Brony not only that if the loco rolled over it was 50-50 that he'd have an escape route as only only one cab door was fitted. The communication corridor along side the off-set boiler, which caused some of the uneven bogie loading, was filled with scrap rail to balance up the bogie loading caused by the off-set boiler.
The driver either was hot or cold depending on which cab he was in, nor could he talk to his fireman whilst driving breaking up sense of being part of a team.
Vector Brony Is there any footage of these being scrapped. That would be great.
Vector Brony Sucks & Ww Will Prove It! 🖕🏿🐥🖕🏿 To All Bronies!
Perhaps the 'root' of the problem was that the locomotive was originally intended for oil firing, which would not have required the dotty offset boiler (and multiple tons of scrap metal used as counterweighting) or confinement of fireman in hot space made hotter during blowback in tunnels. (Oil had to be imported, from countries typically using dollars instead of pounds for exchange, which is why Britain paid such attention to coal-burning standards up through Riddles' standard classes)
Likewise there were supposed to be two sets of chains on either side of the drivers on each bogie (chains drove the leading and trailing axles) but only one side was fitted. This was of more than usual importance because of the design of the suspension; the offset loading causing increased binding and other issues.
I am not sure I would consider the valves in the Paget locomotive to be similar to the arrangement on Leader, which used Meehanite sliding sleeves with a great many ... too many! ... sealing rings for its great plurality of ports. Theoretically this gave an utter minimum of dead space for enormous port opening, the problem being that oiling arrangements were correspondingly very complex and even partial failure of one of the many oil lines would cause accelerated wear, ring breakage, or seizure. The rather fascinating 'figure-8' motion in the original valve drive was intended to keep the sleeves turning slightly radially at the same time they were being moved fore-and-aft for actual valve action, but this wasn't intended as a Willoteaux-like acceleration of effective porting/unporting or, in fact, any kind of rotary valve action a la Paget. I personally think that the tests on Hartland Point (which you should mention here, even if briefly) should have caught all the problems early enough to work out fixes (or determine, perhaps a more likely outcome, that the theoretical gains in dead-space reduction and other concerns relating to poppet-valve or other alternative valve arrangements like Cossart 'drop valves' weren't worth all the problems of keeping all those rings unbroken and steam-tight)
Good video, but a project deserving harsh criticism. An example of very poor engineering management. To say that 'if successful it would have prolonged the life of steam' - what features did Leader have that would have accomplished this? Steam was prolonged on BR, by nearly 20 years, based on proven designs. I think it it unclear how the problems that were being addressed neccesitated that design. For example, if a double cab is a solution, there's a way of introducing that feature without some of the other ambitious features that didn't work, and perhaps getting a working loco. To have ordered and started 5 'off plan' without testing even one was a serious error.
Such a pity..that today with all the technology available we can't produce an effective steam powered engine....that would compete with electric ones. Thank you for this interesting video..
👍👍👍
Small nuke reactor in place of firebox? ( Joke)
Well there must be something... that could be used...maybe a reactor of some kind...great at night...would glow..hahaha 😆😆😆😆😅
@@simonbertioli4696 save on lights then. 😁
Looks like a london underground battery loco on steroids
Wow, weird! Nearly a good idea, some lateral thinking on display but I imagine the amount of preparation before the off in the morning was enough by itself to give diesel and electric trains the edge in operating convenience over steam by then.
Yes but the Bulleid Leader was at that time far cheaper than any diesel.
@@TheDuke-vb9cq Any cost saving would probably be eaten up by paying extra wages for the extra time needed to prepare a steam engine for use.
More like tube train on steroids !!
5 planned, 1 built !! Sounds like where I work Lol.
Good vid. Very interesting.
Thanks.
It would be interesting to combine the Leader class body design and wheel arrangement with that of the LMS Turbomotive and see how that faired.
Interesting idea. How would you get the turbine to drive both bogies. Or are you thinking one turbine per bogie?
As soon as WW2 was over and we were back in peacetime, the government should have been looking at Diesel, and Electric locos to replace steam. That we didn't do this, and it didn't even cross our minds to speaks volumes. I've nothing against steam, or steam trains, but we were still building new ones into the 60's! This steam train does indeed look like a tube train! But what on earth were they doing?? Why weren't they thinking Diesel and/or Electric!?? Mind boggles....
They were. The Dieselisation plan came about in the early 1950’s, and the last steam loco was built in 1960. Pre-grouping railways were already on to electrification, the big 4 all already had a plethora of diesels, and BR ordered the first ones in the 1940s.
Good video, informative and well presented.
Very interesting, never heard of this locomotive before.
This is an interesting and watchable video. Thank you! Do I assume that, as far as we know, there is no motion footage of this locomotive upon (say) super 8?
I bet there is footage of it in private hands.
Flames entering the cab, not popular with crews , crew conditions untenable... hmmm
That is a marvelous understatement!
Warm in winter.
Brilliant video
The result of the 1955 Modernization Plan shows that even an unorthodox coal fired loco like Leader was not going to extend the life of steam. The flexible joints necessary to the design seem like a maintainer's nightmare. Bullied should at least have put the driving wheels in the center of his loco so the power unit was one piece. The Southern Pacific cab forward designs were more successful but they were all fueled by easy to handle fuel oil, not coal.
I went to the same primary school as Oliver, only 70 years afterwards.
Where did the fireman shovel the coal? Is the engine in the middle of the train?
He was in the middle of the loco, between the coal storage area and the firebox. It was very hot, and he had a door on one side only.
@@billcobbett9259 So the "modernity" didn't extend to a mechanical stoker, and a steam turbine driving an electric generator powering the wheels (all known technology since 1884), just the same old. It is interesting that for all the innovations in steam locomotive design since Locomotion 1 (1825) to Evening Star (1960) the steam locomotive stayed in the same configuration with pistons, valve gear and a driver and fireman working behind a boiler, with the fireman shovelling coal from a coal box behind him. Rubbish ergonomics for both operating and maintenance. "This is the way it's always been done lad, no need to change".....
@@SuperNevile the LMS did build a one-off turbine version of the Princess Royal class. Nicknamed the "Turbomotive", it was unfortunately damaged in an accident, and then rebuilt as a standard pistons-and-valve gear loco.
@@alanclarke4646 It’s interesting that experiments were carried out on various forms of rail traction, but the industry stayed mainly with steam technology developed in the early 19th century. Electric (catinary type) locos operated out of Shildon in the early 20th century, and they were toying with diesel electric, but didn’t go further. The underground went electric (for obvious reasons) early 20th century. But when the aviation industry went from the Wright Flyer to Concorde in under 64 years, the inclination not to go to more efficient, more ergonomic (and cleaner) rail locomotion is striking even with the massive coal industry available.
An excellent video. Hello from the Tracy Mountain Railway in Colorado. ♡ T.E.N.
So when and where was it scrapped? It should have been preserved as a static exhibit at least. Never mind. Cheers for the interesting video.
Preservation basically didn't exist in the early 50's when it would have been scrapped.
@@mattlander9119Puffing Billy where Preserved early which was existed since it was built in 1813-1814.
I think if the UK had followed America's ACE 3000 Project (Which sadly wasn't funded enough apparently) Maybe something like this would have worked out in the long run.
2:44 In the US those are called Scullin/Baldwin/Boxpok wheels.
fascinating
Never heard him called "Bull eyed" before !
Lol " Bull eyed " pronounce of the word " Bulleid "
Did anyone give consideration to introducing oil burner rather than coal? Much like the US Southern Pacific Cab forward/first locomotives?
Would it have been better to design it as an oil burner?
His family tell me the name is pronounced Bulleed not Bullide !
I was told years ago it was Bull-ee-id. But I guess the family should know.
It rhymes with the name Reid
@@brando6BL I always thought it was "Bull-Ade" ( as in lemonade). I stand ( or rather sit) corrected.
Excellent video mate will check out your channel. .
The Leader was to replace the elderly 0-4-4t locos that were used on suburban and rural services.
Yes, the M7 tanks.
That's an often misunderstood phrase about the Leader. It had the same route availability as an M7 (similar axle weights) but wasn't built to directly replace the M7.
I feel like the powered chain bogies could've been put to good use regardless, as possibly for some self-driving breakdown cranes, or even self-driving railway artillery cannons, for example.
I doubt that even if the Leader had been sucessful that steam would have lasted much longer than it did. It was the economic conditions in the country that put pay to steam, starting just after WW1 with the introduction of reliable diesel shunters. Gresley's EM1 and Ivatts 10000/10001 were the true leaders.
@Alexander Challis And today's trains are all on time? I don't bloody think so.
A very interesting documentary.
Thank you
Bullied also trued out the design in Ireland. He made it run on peat sincecit was cheaper than coal. It failed. AGAIN.
Well, in his partial defense, he did adapt the design considerably in the 'turf burner' including the substitution of more-or-less conventional piston valves for the sleeve valve arrangement, and fixing the other issues with the bogie design. And interestingly, it appears that the boiler, strange as it looked, was actually effective in making reasonable power from the low-grade fuel. The real reason it 'failed' was less technical than economic: instead of a relatively large and complicated arrangement to burn native fuel, it made better economic sense to use relatively fuel-efficient diesels (whose development cost and parts availability could be shared with other owners)
@@wizlish i suppose but with the turf burner, instead of doing what i thought he would do which is having a cab either end where you could drive it from both sides but only fire it from one end (or make it possible to have two fireboxes), he put both the fireman and driver into a cupboard where all the controlls were. This limited visability and imagine how hot it must have been. Youd better hope he made AC a feature with his steam generator because if he didnt i think most crews would have been cooked before reaching cork. (They were meant for dublin - cork expresses.)
@@Spud607 - This had me chuckling while thinking about the New Zealand E1066 for the Spiral - another somewhat roasty design. But actually there was care taken with additional fiberglass insulation in the backhead and plenum areas of the boiler, and I don't recall heat in the cab area being notably higher than that of a conventional boiler (and certainly a dry-back firebox like the one installed on Leader!)
Remember that none of the contemporary designs (bogie or otherwise!) worked with double-end driving -- they would all involve crew separation or complicated fuel arrangements. If you have oil or pulverized-fuel firing, there is no particular problem in having both crew in an end-cab (see the German 4-6-4 05 003 as built) but the firing provided for the Turf Burner (or a logical alternative chain-grate like the version used in the N&W TE-1) would still require a complicated feed path in the absence of full automatic control (which was not practical even in the latter '50s with Bailey Meter controls derived from nuclear submarine control experience, let alone with cost-effective technology in contemporary Ireland). So the logical thing is to use the time-honored layout for large bogie-borne steam in the United States, with a center cab between bunker and boiler, and rig the locomotive for effective bidirectional control with 'one man per side' making up for the restricted vision. Of course, even then the television system used for CASTOR was practical as a means of seeing what was ahead, and would be a preferred approach technically if the locomotive were to be replicated today...
The thing that most people seem to be forgetting is that the Turf Burner was not a technical failure -- it was just not seen as being as economical as even the pathetic diesels provided to CIE by the early '60s. (Which, it can't be argued with much enthusiasm, it really wasn't...)
Yes and also this train is in a roblox game called steam age
buleed was bullied and his train is now bullieed
My dad worked on tbe Brighton line 1937 to 1982 he must have seen this.
so technically this should have just undergone a diesel retrofit and it might then have been more worth while.
seeing this class of loco on KR Models and how interesting it looks made look up on how rare it was because KR models have doen some rare loco's so far
It’s a steam-powered class 66 crossed with a monster truck and a tube train!
Who else thinks this is shaped like a class 59 or a 66?
yep, so its a "steam shed" then?
@@davidmilne5122 I guess so. Lol
You mean the class 59/66 are shaped like the Bulleid loco as it came first. I think !
59/66 is same but the difference is the details and the sounds. Class 59 where built in 1985 was a prototype of Class 66 where built in 1998, Class 59 has more power than Class 66.
They should have just built a Beyer-Garratt. Much simpler, even if ran cab forward...
I wish one of these had made it into preservation. Massive loss just like his CC electrics. If he'd ditched the sleeve valves and used a more conventional valve gear it might have worked. Unfortunately, nationalisation and the LMS got in the way.
I think automotive-type poppet valves were the coming thing at the very end of steam engine technology. Sentinels used them for their lorries. They provide a much better gas seal.
You only have to watch the youtube video of the rotating, oscillating sleeve valves moving in three dimensions to realise the whole thing was just too complex for its own good. It needed a better design as the orignal would have been a nightmare to maintain and set up at a depot.
And if it had been oil fired, with the fireman's controls in the driving cab...
The fireman was in the middle of the loco while the driver (obviously) was in an end cab. So there was not the level of co-operation that was normally possible. As with many forward-looking projects, too many new features were piled in at one go, so the weakest link discredited all of them, unfortunately.
This class locomotive needed monotube steam generator and automatic injection fuel (gas or liquid) and closed system for circulation water.
Looks like Toby the Tram Engine went to the Gym.
so this is the SDP40F in BR if it was still in testing and hasn’t derailed and has dual cabs.
I have a train book that has loco 36001 (as mentioned in the video) in it. Yes that exact loco.
Britain's first impression of New Zealand. Bullied shows up.
Thanks for the interesting and informative video. I had never heard of this locomotive. Pity it didn't work!
You are welcome. Thank you for the feedback.
i keep seeing commends saying they wish it was in preservation- why? its unique sure, but its absolutly hideous
When something rare is in preservation its usually because of its historical value, not wether it looks good or not, especially in this case with only one being built.
You can't just preserve the 'nice things'. That would make for dull museums with an incomplete history.
The leader was an intersting engine technologically. it also marks an attempt to make steam compete with diesel and electric locos. Though it never would have.
I do wish it had been set aside but BR were never good at preserving protoypes (but back then no-one was).
P.S. Its not a pretty machine but I do kinda like how it looks. Its a beast.
@@chrishartley4553 If lt had been preserved, then the steel sheeting should have been thrown out.
Then all the innovative parts could have been exposed.....the valve gear.
It needs someone to to build one today using modern manufacturing methods, plus getting rid of the ridiculous idea of having a corridor running between the fireman’s footplate and the driving cab in front of the smoke box which meant the boiler was offset, so causing weight distribution problems, having an the footplate accessible from both sides of the loco, so the fireman had more light and air, then it would work. The basic principles were right but the manufacturing and execution of the project was all wrong.
Make it oil burning, then fireman and driver share the same cab.
Yes. The corridor solved a problem that did not need solving.
Oops, my mistake: I thought this was the US Southern Railway, not British Rail. This was an interesting steam locomotive concept/design, however. I did enjoy the video.
I make that same mistake all the time.
First time in my life that's what I thought, But Southern Railway UK where founded on 1923.
If only there were 00 gauge models of at least one of every one that ever existed of every class of everything British railway related of every steam, diesel, electric, DMUs, EMUs DEMUs etc freight etc, passenger, and maintenance etc rolling stock etc. Maybe Hornby in the next 100 years will have achieved this if Hornby legend Simon Kohler has his way I think we will!
ah yes, the brick mounted on 2 smaler bricks
Leonard the Strange-Looking Engine
Bulleid was the last great steam innovator. Pity so many shortcomings and nil will by the then authorities, post Bulleid, to develop the idea.
Here in Germany we had the V2 multiple steam engine powered 19-1001 Henschel high speed loco streamline prototype: de.wikipedia.org/wiki/DR_19_1001
Eh? You mean the DRG 05 003 cab-forward which was was also a failure and converted back to conventional post-war loco.skyrocket.de/data/drg_05_003.htm
Very interesting and a real shame about the problems. The missed opportunity was to fire it on DIESEL so a comparison of efficiencies and flexibility between the IC engine and the EC engine. With stored steam pressure of the EC engine, It could well have accelerated better than the IC engine - and with boiler development and a little automation, not needed a fireman at all.
OIL-firing was used on steam locomotives during a government-backed initiative after the war, although on a limited basis.
The LEADER project did, at one time, include the possibility of OIL firing; there is a reference to both crew members carrying out their tasks seated, which would imply oil, rather than coal, as fuel.
DIESEL is a different technique altogether. It involves INTERNAL combustion, with the fire actually inside the cylinders, rather than in an EXTERNAL firebox heating a boiler.
It has no relevance to the LEADER project whatsoever. The two should not be confused.
@@bingola45 "there is a reference to both crew members carrying out their tasks seated, which would imply oil, rather than coal, as fuel."
Did we not achieve automated coal feed ? It seems the US did.
How you burn diesel depends on the burner whether in a cylinder or not.
@@millomweb Mechanical stoking was tried on locomotives in Britain, but with little success. I've never come across any suggestion of using it on the Leader class, although it might have been possible.
The Diesel engine is, by definition, an Internal Combustion oil engine. There was a type of stationary engine which combined both cycles, at opposite ends of a double-acting cylinder, called the Still system, AND a locomotive was produced by Kitson and Co. of Leeds, using this principle, and, unsurprisingly, called the Kitson-Still locomotive.
You appear to have mistaken Diesel for a type of fuel oil.
It isn't. It's a thermal cycle named for the engineer who patented it.
The two should not be confused.
@@bingola45 "The Diesel engine is, by definition, an Internal Combustion oil engine"
You've added 'engine' to that. I never said 'engine'.
"You appear to have mistaken Diesel for a type of fuel oil."
No mistake - diesel is a specific fuel oil for the purpose of fuelling Rodolph Diesel type engines. But that doesn't stop you spraying it as a mist through a nozzle and igniting that mist - as per heating oil - which isn't vastly different.
AKA: DERV !As it's used as a fuel for DERVs.
@@bingola45 "Mechanical stoking was tried on locomotives in Britain, but with little success"
What were the difficulties with it ?
If you watch Keith Rucker on Vintage Machinery channel (based in Tifton, Georgia, US of A), He spends some of his spare time at an ag/mech museum and one 'little' job he's assigned himself to is to get a stoker engine back into working condition !
America Succeeded on this Idea its called gear driven steam engines
We did too in the UK. Sentinel made many gear driven systems. However, this was very very different even radical!
This thing looks like a E60
They should really make a replica!
They should only make another one if they wish to improve the design. There were obvious tweaks that needed to be done that they ran out of funds for.
@@Dallen9 A replica would be a terrible idea. What a good thing these terrible locos were quickly scrapped and sent for melting and recycling.
High power and low maintenance ..... sounds like SR needed an electric locomotive.
If an engineering department is looking for ways to extend the life of steam traction, then by definition, it is at the end of its useful development. What made this locomotive look odd, was the bogie arrangement wasn't configured as a mirror image.
What made this locomotive look odd was that it had an enclosed cab at each end!
@@bingola45 - It was as pointless as it was weird.
@@channelsixtysix066 The only thing 'weird' about it was that it used steam technology. Mainstream Diesel locomotives used this double-cab bogie layout almost exclusively.
@@bingola45 - The configuration didn't work for a steam locomotive.
The aftermath of war insufficient funding to work on the new design. If they’d been oil burning they might’ve been successful.
Might have been but probably wouldn't have been.
Phil Potter You’re right I’ve done a bit of reading and the design prototype had many mechanical problems
@@likklej8
I can't remember much of my study of the *_Leaders_* but I recall that there were many design problems. One thing was the lubrication of the valve-gear and another was the water supply for the boiler which I think was by pump rather than injector. I think it had a faulty chain grate too.
Looks like somebody took a London Underground body and stuck it on a steam engine.
I dont remember the 1938 stock being put on a Class 66
Everything you said, word for word came from the Wikipedia page for this locomotive.
Bullied would be Buleed. Bullied would be Bulleid. That’s the English I was taught in the forties/fifties. I do know he was always pronounced BULEED. ?
Unfortunately Jim English these days is not taught anywhere as precise as it was back then. Don't even get me started on the deteriorating spelling standards! Cheers mukka.
He overthought it. Instead of having steam powered wheels, he should have linked steam output to a generator and had six traction motors in a simpler bogie. Nice try, but no banana.
Colin Easton - the Swiss did this the other way round during the war and produced a few steam engines which took their (hydroelectrically generated) power from the OHLE to "fire" the boiler (think "kettle") and produce steam for the otherwise conventional engine.
@@1258-Eckhart Similar to the Hornby live steam loco.
I got here from a most wwe heel turns.
Bulleid is pronounced bulleed, and wheel formations do not use the word zero - the leader was an oh-six-oh + oh-six-oh
the wheels of the Leader class look like the GS-4449 class
They look quite a lot like Boxpok wheels indeed, but are slightly different. These "BFB"-wheels were also used on the SR Merchant Navy Class, the Battle of Britain class and the Q1 class - all Southern Railways, where Bulleid was CME.
I Heard this from steam age
💖 why no funding... Why... Dream design...
Are you sure you've pronounced Bulleid correctly?
Does anyone know how to correctly pronounce "Bulleid"? So far I've heard "Bull-ead", "Bull-eed", "Bull-ight". What is correct?
His family say ....Bulleed
@@omepeet2006 It's Bulleed.
@@pmonkeygeezer6212 Chur Bro!
when this bloke gets drunk is he troll-eyed?
Could I just say that the 'ei' in Oliver Bulleid's name was pronounced like the 'i' in 'it'.
yes, of course you may
Mawwiage is what bwings us togevah today...
Some more technical details would be appreciated, otherwise very interesting.
Check out Kevin Robertson's series of books about Leader. Best one is "Leader - The Full Story". Massive amounts of detail!
May have been better if oil-fuelled.
Their adding this to Steam Age in Roblox
Why would British Rail insist on holding the their railway into the steam era when Germany and America were aggressively dieselizing their railway? Doesn't make economic or operational sense from a labor cost standpoint.
Could be because Britain was full of coal. Germany electrified a lot…
@@peterudbjorg
*Bulleid,* rather an autocrat, believed he could design a steam locomotive that didn't need the amount of labour that a conventional steam locomotive. He failed.
Steam was still in use in Germany after being phased out in the UK. The first mainline diesels were introduced in the UK in 1948
@@jackdripper5675
*Britain* got rid of steam locomotives much more quickly than was economical for political reasons. The politicians wanted _modernity_ in everything.
The country was skint after the war, and unlike Germany and Japan, had to maintain a sizable defence budget. Those countries were able to invest in public and commercial ventures that utilised their proven skills in technological innovation.
*Oliver Bullied
Nope it's spelt Bulleid
What was wrong with the first video.
Picture of Bullied was incorrect and the transitions were a little too long.
Well now we know the diesel engine design got stolen
It seems that everything that deviates from the standard steam locomotive design, is not successful ( The French steam electric Heilman locomotives where a technical success but did founder on prejudice & trade union idiocies...) experiments with steam turbines, uniflow steam engines, exotic valve gears & high pressure steam just did not work...
using chain drive for the drivewheels is asking for trouble, and what about the valve gear ? Was nothing better available ?
Where is the point of articulation?
The mid-pint of each bogie, or thereabouts.
@@bingola45 The point of articulation is where the body bends. The body does not bend.
@@georgewindsor6438 The 'point of articulation' is the point around which one part moves with respect to the other.
@@bingola45 The point of articulation is where something bends. What you are describing is a pivotal point.
@@georgewindsor6438 The 'point of articulation' is the apparent point around which something pivoted appears to turn.
An articulated lorry is a good example. Nothing actually 'bends'; the tractor and trailer are so constructed that the overall wheelbase is not rigid.
This is called 'articulation'.
That's on roblox steam age