Gibbo675

Hi Mick, You make some excellent points in your above piece and may I verify what you say with some reasoning. In design and construction the GWR regulator is a a horizontal grid type regulator valve in exactly the same way that LMS and BR Stds are constructed. Some locomotives have vertical grid type regulators but the principle is the same. The valve body is of cast iron with the main valve being of bronze, about an inch thick, mounted on top in such a way that when operated the slots in the body and valve open and allow steam. There are either three or four slots about 3/4"-7/8" bye 6"-9" long depending upon the size of the locomotive, On top of the main valve is the pilot valve this is a smaller version of what has just been described with either one or two slots about 1/4" and perhaps 3"-5" long. The pilot valve is arranged so that only it is moved bye the regulator linkage in the initial movement of the handle with the main valve being collected and actuated over the remaining travel of the handle. The only difference between the GWR type and the others is that the GWR situated their regulator valves in the manifold housing in the smoke box and above it was an atomised oil feed that lubricated the sliding faces of the of the valve. In the case of the LMS and BR locomotives the regulators are atop of the main steam pipe, sometimes known as the dry pipe, and as a consequence were not fitted with an oil lubrication supply for injecting oil into the boiler would cause all manner of trouble the most prevalent being foaming which may lead to priming. It is the fact that the GWR regulators were lubricated that made them easy to operate in comparison to the other locomotives. The LNER and SR used double beat type regulators in their pacifics and latterly the LNER and following on BR used Melesco poppet valve regulators on their pacifics, Here is an interesting link with some good diagrams: https://janfordsworld.blogspot.com/2016/09/locomotive-regulators-part-2.html It would seem to me that two of the reasons for GWR locomotives being sure footed are that they have relatively constricted steam circuits and also the cylinders were mounted horizontally which greatly reduced the ability of the piston thrust to roll the locomotive upon its springs upon starting. Any one that has ever ridden on a Crab will know all about how pronounced an effect that may be. Gibbo.

Hi Mick, You make some excellent points in your above piece and may I verify what you say with some reasoning. In design and construction the GWR regulator is a a horizontal grid type regulator valve in exactly the same way that LMS and BR Stds are constructed. Some locomotives have vertical grid type regulators but the principle is the same. The valve body is of cast iron with the main valve being of bronze, about an inch thick, mounted on top in such a way that when operated the slots in the body and valve open and allow steam. There are either three or four slots about 3/4"-7/8" bye 6"-9" long depending upon the size of the locomotive, On top of the main valve is the pilot valve this is a smaller version of what has just been described with either one or two slots about 1/4" and perhaps 3"-5" long. The pilot valve is arranged so that only it is moved bye the regulator linkage in the initial movement of the handle with the main valve being collected and actuated over the remaining travel of the handle. The only difference between the GWR type and the others is that the GWR situated their regulator valves in the manifold housing in the smoke box and above it was an atomised oil feed that lubricated the sliding faces of the of the valve. In the case of the LMS and BR locomotives the regulators are atop of the main steam pipe, sometimes known as the dry pipe, and as a consequence were not fitted with an oil lubrication supply for injecting oil into the boiler would cause all manner of trouble the most prevalent being foaming which may lead to priming. It is the fact that the GWR regulators were lubricated that made them easy to operate in comparison to the other locomotives. The LNER and SR used double beat type regulators in their pacifics and latterly the LNER and following on BR used Melesco poppet valve regulators on their pacifics, Here is an interesting link with some good diagrams: https://janfordsworld.blogspot.com/2016/09/locomotive-regulators-part-2.html It would seem to me that two of the reasons for GWR locomotives being sure footed are that they have relatively constricted steam circuits and also the cylinders were mounted horizontally which greatly reduced the ability of the piston thrust to roll the locomotive upon its springs upon starting. Any one that has ever ridden on a Crab will know all about how pronounced an effect that may be. Gibbo.

Hi Marc, But it's Friday !!! Gibbo.

Hi Clive, You might wish to put a few words into this thread with your turning of tank engines lark: Gibbo.

That and the white, five pointed star painted on the cab side !!!

Hi Simon, That is why I asked the question for I am more than well aware that certain batches of 08's were shopped from new with wooden framed doors that were varnished wood. On the subject of cab doors the later ones were of cast aluminium and the engine bonnet doors had either external or internal hinge strapping, some riveted and some welded depending upon where and when built, this is before recourse to discussing the different arrangement of cabinets upon the running boards. Gibbo.

Hi Brian, Which door is missing, or am I missing something ? Gibbo.

Dear Whickam Green, I would have thought that rather obvious which is precisely why I wrote, "where and when possible" in the bit you left out of your creative editing of my original post and funnier still that you included, "to and from work" in the bit you left in. I despair, Gibbo.

Hi Folks, In conversations with old hands from Bolton shed some years back when at the ELR it was generally accepted that tank engines, of which there were L&Y radials and LMS 2-6-4's, were always turned where and when possible. The exceptions were if late running was encountered to save time or if the locomotive had a diagram that included a lot of short to and from work. If the latter was the case then the engine might well be set to deal with gradient profile or sighting considerations being taken into account. Gibbo.

Hi TS, I have to say at the rate, quality and enthusiasm that you produce models I don't see too much evidence of can't be bothered. Gibbo.

Hi TS, It looks better in the above photos than it did on last evenings YouTube video. Your locomotive has just the right look of a small lightly built 0-4-0 with quite large wheels that also a cab and tank of its own styling. I have to say you really do go for it on the home made front, well done for that. I have always enjoyed kit bashing and scratch building for what I would guess are similar reasons, so much better than opening a box that came from Chinese factory. Must dash, the lunacy of BAA wagons await. Gibbo.

Hi Corbs, A most plausible and convincing mock up. I have to say the stepped up part of the tank at the front is of better proportion than that of one of the conversions that you have done previously that seemed a bit low. I've been having great fun in the Merchant Navy Adhesion thread thanks to you also, it would seem that the term "myth and legend" is not altogether approved of !!! Enjoy, Gibbo.

Hi RA, What you mention is another one of those over used "myth and legend" type topics, however should you draw a force diagram of the system that represents a locomotive upon starting a train you will see that the reactions will indeed transfer weight onto the truck. This fact is then, and without any further thought into the mathematics of the system or any other factors involved, spoken of as though pacifics with heavy trains wheelie away as would a motorcycle with its throttle pinned in first gear. I have yet to see figures to suggest the percentage change in axle loadings that would significantly cause such problems for pacific type locomotives especially the Bullieds. I'm not sure what the 0-60 mph is for the average steam locomotive but it certainly is not under four seconds as are most motorcycles. I would suggest that inclined cylinders would have a much greater effect than that of weight transfer onto the trailing truck ever would even considering a minor surge in the water level toward the rear of the boiler as a result of the change from a static to a dynamic system due to the starting of a train. The centre cylinder of a Bulleid is 1:7.75 with the outer pair set at 1:40 to the horizontal. It is the centre cylinder that will have the greatest effect and the reason that the GWR under Churchward used horizontal cylinders. The locomotives are right hand lead, followed by the left and lastly centre in order of admission and the crank axle is through balanced for the originals and individually balanced for Jarvis' de-tuned ones. I am thirty years past caring to do hard sums that I didn't like doing thirty years ago, so don't ask ! As an aside I once worked with a chap that was involved with the initial testing of the class 91 electric locomotives, he noted that their 0-60 mph figure is twelve seconds, but only light engine. I might add that their wheels are even stiffer than Bulleid wheels by virtue of being a smaller diameter disc type wheel if only to dispel another one of those myth and legend type topics. Hey-Ho, it's back to the naughty step for me ! Gibbo.

Bless !

Hi Folks, In an attempt to redeem my silly self from my earlier comments which were deemed rather prickly in nature may I offer the following; Valve gear: The Bulleid valve gear is a chain derivation of Walschaerts that was designed to replicate the operation of Caprotti Gear that the locomotives were envisaged to have been fitted with but for WWII. Caprotti gear gives full port opening at any given cut off which allows for both free filling of the cylinder and a free exhaust for reduced back pressure and improved power. The Bulleid valve gear achieves this by arranging for the valve head to be accelerated from the point of cut off to the point of lead to a much greater extent than standard Walschaerts to allow fast port opening and also to allow for a period of lag at either end of the travel while the valve is open to admission. The three troubles with this arrangement upon starting in that steam is admitted to the cylinder a lot less gradually than with standard types of valve gear as the valve opens and for want of a better description shocking the piston. The second feature is that when the pins and bushes in the system become worn the valves will under travel at slow speeds and over travel at speed so when a slip occurs the valve will convert from a state of under travel to over travel instantly exacerbating the slip. The third feature is that in worn condition the drive r may have to apply more steam as the valves may not be opening by enough to allow for easy starting this will also affect starting. Valve gear drive chains: The type of chain used to drive the valve gear is of the Morse Hi-Vol type and was specifically chosen so that when it stretched in service it would ride out upon the teeth of the sprockets and keep the sprockets in synchronicity with each other. When a horizontal chain is fitted up there is four inches of slack in the loose leg of the chain, should this not be the case the chain would be over stressed with the rise, fall and twist induced in to the chain. The vertical chain has a much easier life and its slack is less than an inch. This type of chain is used for cam timing in internal combustion engines for the very same reason. There are two types of slack adjuster one is an angled bracket that is appropriately packed with shims and fixed by seven one inch fitted bolts and the other is a pivoted bracket with a screw adjuster similar to that of a brake pull rod adjuster. The effect of a slack or worn chain upon valve events is in fact less than the difference induced by full axle box travel upon a standard type valve gear. Oil Bath: The oil bath contains forty gallons of oil and this forms a depth of only four inches when at rest, well below the axle of the driving wheel and so cannot leak out from there. The sides of the oil bath are in the main formed of the main frame plates although the undersides and ends are from 1/16” thick steel welded to light angle framings. Vibration and flex do occasionally cause small cracks to propagate, however the oil merely weeps and at a rate less than the amount of oil that may be dropped by any inside or multi cylindered locomotive. Depending upon the size and position of the cracks they may be welded without need of dropping the oil from the sump. In my experience the greatest cause of oil leakage from the oil bath is that of hot atomised oil drifting from the vents in the top of the oil bath when the locomotives are worked hard. It is this that caused the fires in the lagging of Bullieds until belly sheets were fitted to the underside of the boilers to prevent sparks form the brake blocks from igniting the oils soaked lagging. I feel it safe to say that unless there is a newly formed crack in the oil bath or a burst pipe to the oil filters, then the amount of oil dropped from the oil bath is less than from any other inside or multi cylindered locomotive and also that any oil that does leak form the bath drops into the four foot in any case. Reverser: The type and the position of the steam reverser are both poor in view of the size and power of the engines. The type of reverser is not self trimming and will not reset itself to position should it loose its position as does the Raggonet type and should the oil seals become loose or fail then it will not hold the gear in position properly. The maintenance of the reverser is compounded by its position under the boiler just ahead of the firebox, the filling and bleeding of the oil cylinder is quite difficult due to space available to get a can into position over the filling tubes. Operation of the reversing gear is simple enough but it will only work properly when in good order which means that it needs to be checked daily. Wheels: The Bulleid derived Boxpok wheel is indeed a stiffer wheel than a comparable diameter wheel with ordinary spokes but how this actually effects slipping to any great degree I would suggest to be wishful thinking. The reason I say this is that the SNCF 141R class locomotives were delivered with both standard spoke and box spoke wheels and to my knowledge, and I stand to be corrected, no differences in adhesion or traction were ever noted. Steam circuit: Bullieds have a very large steam circuit that took on all of the ideas of Chapelon, the steam circuit is actually further increased as the engines are of outside admission type which gives a greater manifold effect for better steam distribution when working at speed. The effect of this is that should a slip start it will continue until all of the steam is used up. The regulator valves also have a large free area and as such should they be opened even a little too much then a lot of steam will be put into the steam chests with the obvious results should a slip start. Weight Distribution: In comparison with a Britannia a light pacific weighs eight tons less having a ton a three quarters less upon each driving axle and a comparable ratio less on both the bogie and the truck. This in itself should not be a great problem for the adhesion factors are similar to the LMS pacifics and [£] Seventy One Million which seem more than capable of starting and pulling heavy trains more than adequately. My Own experience: I have driven the following locomotives (BR numbers and USATC*) that are class 6 and above; 5029, 5820*, 34027, 34067, 45593, 45690, 46201, 46203, 46229, 46233, 60007, 60103, 60532, 60800, 71000 and 92203. I have to say of those listed the two most slippery locomotives of the lot were the S 160* and the 9F 92203, the worst of the passenger locomotives were the LMS Jubilees, the Duchess’ and the A4. Go figure !?!?! http://1.bp.blogspot.com/-WYk8aSfb2Fw/VM4y3ptI6RI/AAAAAAAAkBI/_fwtd8VnPuU/s1600/valve_gear_dia.bmp Gibbo.

Hi Phil, I feel that what you have written is both correct and fair. I too have experienced high speed slips at speed on pacifics and also 4-6-0's the fastest of these by far was on the footplate of 6229 near Garstang on the up heading toward Preston. The locomotive was travelling at 97 mph and it suddenly started shaking violently, looking at the speedo the indicator needle had gone right around the dial and was hard up against the underside of the rest that normally holds it at zero. At a guess I would say the wheels were going at approximately 130 mph. The regulator was shut and the slip was corrected, the driver then attempted to judge the moment to reopen the regulator just as the wheels rotation dropped to road speed, as this happened the train gave the locomotive a great bump through the tender and the train speed had dropped from 97 mph to about 85 mph in the time it took for the steam within the circuit to dissipate. The cause of the slip was a rough ride caused by a wet bed in the ballast. Variously, other causes of high speed slips can be greasy point work, flange greasers on tight curves, water from wet tunnels or over bridges, level crossings and platform ramps that seem to affect the formation of the ballast shoulder. Gibbo.

Hi Gaz, The Cartic-4 laser cutting was done by York Modelmaking and I have to say that they are very helpful in all regards. I may see what they say with regard etching art work although it was my impression they seem to be more in to the laser cutting. Thanks for the suggestion, Gibbo.

HI Quarryscapes, Thanks for that, I had read that as though they accept CAD files for alteration and not conversion form pencil and paper to CAD, Thanks again, and I shall be contacting them as soon as. Gibbo.

Hi Quarryscapes, From what I see of their web site 4d only accept CAD files as art work and don't do conversion from pencil drawings to CAD files which is the problem I have, or have I miss read what they offer as artwork services ? Thanks all the same if I am mistaken. Gibbo.

Hi Folks, I currently have two projects that require etched brass components to complete them and I would like to know if there is any one that may assist me in developing a CAD drawing for the production of the etched brass components. I shall be able to provide fully dimensioned pencil drawings for a CAD file to be produced, the reason being that I am unable to operate CAD programs and I'm fast approaching the stage in life where learning new skills does not come easily especially for one off type work. The parts required are: ladders, hand rails, brake wheels , loading flaps and gratings for a Cartic-4 set and the ladder and walkway grating for a CSV / CSA Fly Ash hopper wagon. The Cartic-4 is laser cut with printed bogies and the Fly Ash wagon will be a printed item although it is not yet known if it will be one piece or as a kit of parts to be assembled. The etched brass details will be the finishing touches to the main part of the kit component parts which are to fine and fragile for either laser cutting or printing. Photographs below: Prototype test cut of the Cartic-4 set. Mock up of the CSV / CSA Fly Ash hopper wagon kit bashed from a Dapol kit from which a pencil drawing was developed. Thanks in advance for any assistance offered, especially so if it is not too expensive !!! Gibbo.

Hi LMS, Thank you for your kind reply. I shall in time gladly reply to comments that do not make any real sense or are that are just plain wrong in good time. I do not and shall not offer my experience as a belittlement to anyone at all, more that people may actually learn by way of my experience. One thing I can tell you for sure bye way of bitter experience is that, "when they are good they are very, very good and when they are bad they are horrid!", to quote the well know nursery rhyme. Gibbo.

BAA Steel Carriers Hi Folks, I've been busy in the real world, ie. not toy trains, for most of the last month and so not much has been going on or posted on this thread model wise. Any way, with the kitchen and bathroom finished, considerably less dust and mess about the place here I am back. I have always fancied a rake of steel carriers to put behind a pair of early AC electrics and so rather than complete any of the above projects I went straight out and bought five of Cambrian's BAA steel carrier kits. I have built various Cambrian kits before and they always seem to go together well so I thought why not, this with the added bonus that they are a third of the price of bought ones and I get to build them my self. The kits went together well enough although I find that Cambrians method of using a 45* bevel as a mating surface in corners a little tricky. I have to say I much prefer that there is a square edge and a rebate, as with other kits to be a better system, although only minor detail that with care is easy to sort out though. I found that when assembling, fixing the decks to the frame sides it is best to position the decks appropriately and then secure one end to the head stock using a steel straight edge placed between the ribs bearing upon the top of the frame, a gentle squeeze then finds the level through the sides and the deck bye way of the straight edge. Once both ends are fixed I can work from the middle out in either direction to ensure the top edges of the frames are flush with the decks and that the sides are straight .The only real gripe with the kits is that there is a web between all the ribs in the tops of the decking that requires filing out to give the correct end on profile. I suspect that these ribs act as runners to ensue that the deck ribs do not void during the moulding process, more of a fiddly job than a problem though. So far all five have been built up and the brass bearing fitted to the bogies, I have only wheels enough for one with some on order, with the first coat of bauxite applied. I have ordered two sets transfers from Steve at Railtec so that I may build a second batch when I buy some more. Gibbo.

Hi Al, My thoughts so far have been generally tongue in cheek as a way to weed out all the "Bulleid Bashers" (a lot of which have never had anything to do with them other that look at photographs, no doubt there will be some that bite upon the bait including what I have just written !), I was going to wait until all the sillier comments had been made and then comment sensibly to explain the silliness away. But what the hell its Sunday and I wrote what I wrote. I shall write about what I know through my experience of taking a Barry wreak to a working main line locomotive in good time when a few more comments are available to be challenged should that they be nonsense with good reason and experienced example. Gibbo.

My dear LMS 2968, May I ask you a question: Have you, at any time, put forward any of what may be termed "myth and legend" ? The reason I ask is that for if you have not done so then you for one, along with all the others that have not done so, are not included in my put down of "myth and legend" and only of "myth and legend". Do please see what I have written for what it says and not what you wish to be offended by. Gibbo.

Hi Corbs, I have had a good read of the comments posted so far and some are quite usual in that they display a lack of understanding of 1. basic physics 2. how locomotives actually operate and 3. the detail differences within various types of locomotive design and modes of operation that such comments totally ignore. This is before we even mention ham fisted drivers, poorly set up or maintained locomotives, tyre wear and track defects. Myth and legend is a mighty force and efforts to dispel it are generally fruitless due to the gusto to which myth and legend progenitors apply yet more myth and legend to any answers to questions raised. Why spoil the truth with a good myth and legend ! There will now a barrage of abuse toward an man that not only rebuilt Tangmere after a so called Bulleid expert (myth and legend twerp) had cocked it up in the first place leading to a catastrophic failure to its valve gear. You may wish to note that after I had rebuilt it Network Rail upgraded it from a class 7P to a class 8P. I might also add that 34067 didn't very often slip when I was driving it if that tells you any thing. Gibbo.