Pacific231G

I wonder if the slots might start to appear in RTS models. Although I've not yet seen a model fitted with them, MOROP have recently updated NEM370 http://www.morop.eu/...s/nem370_f.pdf that specifies the dimensions of the slot in a buffer beam to fit a coupling hook. it was originally published in 2000 but has been updated this year along with NEM111 (minimum curves) http://www.morop.eu/...es/nem111_f.pdf which now includes a separate table for couplers where the buffers are in contact which would include screw couplers but also others such as Alex Jacksons.* There is also an annexe to NEM111 http://www.morop.eu/...nem111an_f.pdf looking at the constraints on prototypical side buffer/screw coupler and how these apply to models which seems pretty well thought through.. NEMs are currently only available in French and German but I'll try to translate the annexe which is interesting. All this seems to indicate a growing interest in continental Europe in using more prototypical couplers. NEM370 only gives the slot dimensions for H0, S, 0, I & II so I suspect there may be more interest in this in the larger scales * Minimum curves to avoid buffer locking and derailments are given in terms of muitliples of the gauge so are scale independent but I think they're assuming NEM standard RTR wheelsets rather than proto. I know that some French modellers use Alex Jacksons but not whether that's true across Europe.

I've got a few of these which are rigid coupling bars for NEM boxes moulded to resemble screw link couplers. (loose couplings largely disappeared in continental Europe very many years before they did in Britain) I'm not very keen on them not so much because of the height being wrong (it would be more wrong in OO) but partly because a tightened screw link wouldn't keep the buffer heads separated like this but mostly because, although NEM boxes allow easy interchange of couplings, it does take a certain amount of force and or fiddling with tweezers to do so. This is fine to do occasionally when replacing couplers but, unless the vehicles can be kept semi-pernanently connected, pulling these out every time you need need to put stock away and vice versa does seem to me to risk damaging some detail on the model. Ironically the reason for positioning couplers beneath the drawbar seems to have been partly to allow the buffer beam and its hook to be kept intact.

The human eye adjusts itself for lighting conditions in a way that no camera can but If your camera can do a proper white balance that may help.

Meanwhile in the rest of Europe light railways used almost no signals (unless for a junction with a main line) and points were generally held over by weighted levers- usually local ones. They did though have very strict rule books and were no more prone to accidents than light railways here. It does seem that, though the Light Railway Acts were designed to encourage the development of vey economical railways particularly to open up poorer regions, the authorities just couldn't let go of their heavy rail thinking. Light railways weren't that much cheaper to build and equip and in the end there were relatively few public light railways in the British Isles.

Interesting, The narrow gauge there seems to be laid with quite heavy rail. With over 21 000 kms of public narrow gauge railways You'd have once found interchange stations between public railways of different gauges in the high hundreds in France alone. Add industrial and agricultural railways and the total would probably be well over a thousand. Most public interchanges were between standard and metre gauge lines but there were about 450kms of public sub-metric NG lines- all but one 600mm- so a few places where a metre gauge line - usually a roadside tramway- connected with a very local 600mm gauge line serving a resort or even a single hotel.

True and when the ZB was still all steam and carrying quite a lot of freight as it was when I last saw it Jenbach was even more fascinating than I assume it is today. The metre gauge and partly rack Achenseebahn is on the opposite (North) side of the OBB main line from the 760mm gauge Zillertalbahn so there's no physical connection. My memory may be false but I don't think there was any mixed gage track associated with the Achenseebahn though the ZB handled SG wagons on transporter wagons so their yard had plenty of interesting ironmongery. At Volos in Greece there used to be a section of triple gauge track (1435, 1000 & 600mm) running down a road to add to the fun and all three gauges were used by public railways. I think this may have been unique in the world though there have been a few examples of triple gauge where one of more was an industrial railway. The two other triple gauge stations I know of are Montreux and La Tour de Carol near the Franco Spanish border. La Tour de Carol is three termini in one but only the metre gauge Cerdagne railway is narrow gauge. It runs from its own bay though and doesn't get mixed up with the border arrangements though there may have once been mixed gauge in the goods yards. I've not visited Montreux which has 1435, 1000 and 800mm gauge lines so I've no idea if there is any mixed gauge track there.

Hi Pat I've found a couple of photos including the crane. This is the clearer one https://www.flickr.com/photos/brizzlebornandbred/2056673243/ and the ship is the Harry Brown. This shows the whole scene but it's not clear enough to see the rigging. http://www.b-i-a-s.org.uk/images/tambling_Pools_Wharf_Bristol_harry_brown_Arco.jpg Difficult to be sure how it's rigged but it certainly looks like a bog standard S&P level luffing crane with a counterweighted jib and a usefully small one at that. With the toplis riigng there is usually only one lifting cable between the hook and the jib end pulley. There are two cables here but you'd need a second one to open and close the grab. It looks like there could be six lines between the two sets of pulleys so its possible that both lines follow the same reaves which would make it level luffing but that does seem like a lot of rigging. There would be no particular advantage in level luffing for the actual handling of this type of cargo but, because the load doesn't rise and fall when the jib is luffed, the luffing mechanism requires far less power so can be a crank lever rather than a luffing drum.

Hi Andy I've been doing a bit more delving and found this postcard from the 1930s of a crane at Calais that looks rather more like the Airfix type. It's not very typical though and the rather heavier crane behind it looks more typical. In the actual port they also had these cranes and from the sailing vessels behind these would be quite early Though larger these seem to have a similar jib arrangement to the Airfix model though these are grab cranes. With these I think there are two cables with relative movement between them opening and shuitting the grab. It would be hard to do that if both cables had to be reeved over four pulleys. and in any case a grab crane would probably have less need for level luffing.

Water vapour may have a stronger immediate greenhouse effect but it's far shorter lived, it tends to fall as rain, whereas carbon dioxide is cumulative. Because warm air will hold more water vapour it may tend to amplify the warming caused by CO2 emissions but they're still the real problem. That's for water vapour released at or near the ground. Injecting it directly into the upper atmosphere may be far more significant and the water vapour released by jet aircraft at high altitude may be as much of a problem in terms of global warming as the CO2 they release. That doesn't make increased use of hydrocarbons on the ground in any way harmless, especially when used in very inefficient ways such as road transport, it's just not as harmful as the same energy generated from burning coal.

The CO2 it gives off is the same CO2 that the plants making up the biomass absorbed from the atmosphere while it was growing using solar energy to drive the process. So the cycle is in ther same balance as when you eat something you've grown. Looking at the whole cycle environmental impact does make sense so yes it may be pointless to ship wood pellets half way round the world- then again it might not. If we've used vast amounts of oil derived fertilisers and fuel to grow the biomass then it probably doesn't. The reason why natural gas produces less greenhouse gas than coal per energy unit is that most of the energy in coal is in the form of carbon - there is some hydrogen and a few other things but it's mostly carbon- and the burnt carbon almost all emerges as CO2. With hydrocarbons you're burning both hydrogen and carbon, generally about four hydrogen atoms for each carbon atom, so though it does produce CO2 a lot more of the combustion products are H2O. I agree about having multiple forms of generation but a far larger proportion of that needs to be renewable- which mostly means ultimately derived from solar energy- if we're not to make the planet far less habitable for us. It's not about "Saving the Planet", the planet couldn't care less what crawls around on its surface, it is about not artifically creating a radical departure from the climatic conditions that enabled us and the species we've evolved to cohabit with to evolve and thrive.

I think high speed level luffing came with the serious development of electric cranes. Before that steam, and in busier ports hydraulic, cranes as well as hand operated cranes were the norm. Travelling steam cranes usually ran on standard gauge track rather than the portal type on widely spread rails that could straddle a line of wagons. A lot more general cargo handling was also carried out by the ship's own derricks though they continued to play a role and still do. This postcard, from the collection of a French aquaintance, shows a self propelled steam crane in action on the quayside in Dieppe sometime between 1900 and 1910 when it was posted. Similar machines were also used in Britain and they continued in use for a suprisingly long time. There were some good examples belonging to the GWR on Weymouth quay. Note the chains with screw links at the four corners of the chassis to stop the crane from toppling. In this postcard view from my own collection you can see that while two modern electric horse head level luffing cranes had been installed with Dieppe's new passenger ferry terminal in the 1950s, four of the steam cranes on their own track were still working the cargo ferries that ran their own service to Newhaven and went on doing so until the early 1960s when two more of the same electric cranes were installed. I can also remember seeing crane engines that ran on ordnary tracks still in use in shipyards in the 1960s. I assume the Airfix crane must have had a prototype and level luffing cranes were by no means universal, but I don't recall ever seeing a crane of that type mounted on a travelling portal on rails.Maybe it worked in a scrapyard or somewhere and I notice that Dapol now call it a travelling crane rather than a dockside crane. Pre WW1 an electric travelling crane would have been very modern but they did exist There's a good section on quayside crames in Mike Smith's website about railway goods. http://mike.da2c.org/igg/rail/12-linind/dock-ch.htm

I think Stothert and Pitt generally called them high speed level luffing cranes so I guess the clue is in that. The economy in electricity consumption of not lifting the load when luffing in was one of the main attributes claimed in the various patents and the direct crank linkage for the jib movement would have been a lot quicker than a luffing drum . There was an interesting variation on that in the Toplis' lifeboat davits (for multiple lifeboats) as used on the RMS Arundel Castle for about half of its boats (qv The Engineer May 13 1921) Here, the lower power needed to winch the boats out could have been vital if the ship's main generators had been disabled as they likely would in a sinking. The davits could be powered by a small emergency generator on the boat deck or even manually. The cranes were always associated with manual cargo handling yanking bags and boxes in and out of the holds or baggage, post and even cars on and off ferries. I'd like to know what was the smallest such crane they supplied as that would probably be the best subject for a model.

I've now found Thomas Mannock's patent application (1922 GB196450A) and he used a single line between the fixed pulley and jib head I tnink using equilateral triangles but his diagram should make it clear. I don't know if the luffing is quite as level as it is in the Toplis system. This has advantages for heavier loads in that it puts less wear and tear on the hoisting line which only passes over two pulleys rather than four and is far simpler if multiple lines are needed at the hook. I'm still trying to figure out how such simple types of rigging were ever patentable.

Hi Andy In principle yes though as Simon has calculated it's not quite so simple. Toplis' original patent actually suggested that you could achieve the same result with different numbers of lines. The key ratio is between the variation in length between the two sets of pulleys and the vertical rise and fall of the jib head. For three lines (and I've not come across any other number actually being used) that would only equate precisely to the ratio between the tower height and the jib lenght if the jib was vertical so for the nornal range of jib angles the best ratio seems to have been found empirically. I had assumed that Toplis had come up with a set of solvable equations to describe his system but I don't think he did and assume he actually found the best tower height graphically. The 1960 article in The Engineer also mentioned two other level luffing systems one patented by Mannock in 1922 and the other by Walls in 1928. I'll now try to find those. Simon, congratulations on your evening's work, it's more than I managed in weeks of head scratching and scribbling in notebooks on the Tube but I was looking for an analytical formula when I clearly should have been seeking a numerical solution.

Chris Mead has a couple of rather large dockside cranes on his Overlord layout based on Southampton at the time of D-Day but I'm pretty sure they were scratchbuilt. Scale Link do have a N scale fret for a dockside crane which might be level luffing but I could only find the fret and no pictures of the assembled model on their site. There are some European models from I think Faller and Artitec but they're either horsehead or in the case of Artitec (in 1:160 scale) something that looks rather like an articulated horsehead jib but is actually fixed. The Airfix crane annoyed me as a kid as I bought one, assembled it and realised it had little in common with any dockside travelling crane I'd ever seen.

Thanks 34C & Simon. US patent 460649 is a way of mounting the operator's cab on a horse's head crane so that it's close to the end of the jib. It looks pretty terrifying for the crane driver but I suppose they're used to being suspended in mid air. Cranes and the Toplis system in particular have long been a favourite with adult Meccano enthusiasts and somewhere I've got the plans for a simple (ish) demonstration model that allows you to adjust the height of the fixed pulleys to investigate the optimum ratio. I think though that I now know why none of those articles really explain why the Toplis system works. Thanks to an article in The Engineer, from 1960 which finally gve me the date and number of the original 1912 Toplis patent application, I now have that patent and if anyone's interested it is United Kingdom Patent 1912 22704-A (http://patent.ipexl.com/GB/191222704-a.html ). The application describes the principle in very general terms and there is none of the complex trigonometry that a full mathermatical description of the system would require so I suspect that the precise relationship between the jib length and the height of the fixed pulleys was arrived at by a certain amount of trial and error (or empirically if you want to be posh about it) What is odd is that the basic arrangement of four pulleys is so simple that you wonder why every ship's bosun since Sinbad wasn't already completely familiar with it. I rather suspect they might have been. However, analysing it completely is a rather different matter and while it would be an interesting exercise for anyone with a real grasp of this sort of maths it's well beyond my ability. The equations derived in the April 1960 article in The Engineer (pp 735-738) by Dr. E Lightfoot and M. Girgraph MSc.are fiendishly complicated and even then they used an empirical equation supplied by one of the crane manufacturers. They applied a computer (not easy to get time on in those days) actually a Ferrranti Pegasus, to find the best pulley positions by number crunching the variables to produce a graph that would show the optimum values. If anyone is interested the 1960 article is available online from Grace's Guide to British Industrial History which includes scans of The Engineer from 1856-1960. However, if you're interested in engineering I must warn you that once you go in there you may never be heard from again !! http://www.gracesguide.co.uk/Main_Page

This came from our topic on slide rules and trigonometry. It was rather off-topic for that discussion but since it seemed to attract a high proportion of RMWeb's mathematicians I thought I'd try to get an answer. . This is a question that's been bugging me for years and though there are plenty of descriptions I've never found a satisfactory explanation. I know how this device works but I've never seen a satisfactory explanation of why it works. Creative Commons This crane is one of four preserved in Bristol but almost any model of a tradtional British port needs at least one or two of them. It's a dockside crane built by the Bath company Stothert and Pitt using their Toplis Level Luffing system. Though this is quite a large one smaller versions were to be seen at places like channel ferry ports, to handle the gangways,mail and baggage, but anywhere where general cargo was handled and there are still a good number of them in Southampton Docks. When a crane's jib is raised and lowered- "luffed"- to bring a load towards or away from the crane it also moves up and down. With the dericks on board a ship that's no real problem as you can simply hoist the load to a suitable height and then swing the derrick round to bring it on or off the ship. For a dockside crane though, designed to handle cargo as quickly as possible, you really want to bring the load as directly as possible between the ship's hold and the quayside. Level luffing means that as the jib is raised and lowered the load remains at the same level which makes handling far easier and so faster. Outside of Britain and in more modern cranes the horse head system seems to be more commonly employed and it is based on simple geometry. The Toplis system seems to have been patented in 1914 by Claude Toplis, Stothert and Pitt's Chief Engineer, applied for his patent in October 1912 and you may be able to see from the photo that it works by having pulleys at the end of the jib and also on a pylon above the cab where the machinery is housed The load is on a hook at the end of a single hoist cable but, instead of that cable being run straight out from the hoisting drum, it first passes over a pulley on the tower to a pully on the end of the jib then back to another pulley on the tower before finally returning to a second pulley at the end of the jib and down to the hook. The hoisting cable is therefore tripled between the two sets of pulleys. This diagram is based on one in an old Meccano guide with only the hoist cable shown (in red) The ratio between the height of the pylon above the effective base of the jib T and the length of the jib J is critical if the hook is to remain level but I've never seen a mathematical description of the system. The principle is simple. As the jib is lowered or raised the distance between the two sets of pulleys increases or decreases and that pulls in or pays out enough cable to compensate for the rise and fall of the jib. What I can't figure out is the maths that determines that the hook is completelly level and what range of jib movement it works over. Anybody got enough maths to figure it out? The diagram is very simplified and real dockside cranes normally had counterweighted jibs and, because the load didn't rise or fall, luffing required little power and was often driven by an arm connected to the jib rather than by a winding drum and cable. This also made operation much faster. The other thing I never understood was why, when dockside cranes like this were a familiar sight in almost every port or quayside large or small up and down the country, Airfix produced a kit for a "dockside crane" (now I think in the Dapol range) that was completely different and so untypical that model railway quaysides that used them never looked quite right.. .

Anywhere with a street level entrance above platform level could be a candidate for this. Ealing Broadway District Line comes immediately to mind. It was a separate District Railway station immediately north of the GW/CLR station with a short train shed (gabled roof) which still exists and its own station buiding at street level, now a short row of shops but still carrying the District Railway name in their stonework. Street level is well above platform level so stairs near the end of the platforms led to the station building and there was AFAIK no pasenger circulation behind the buffers. It's essentially the same arrangement as in Cyril Freezer's original Minories plan except that one face of the island platform is shorter so there is side access to the Central Line platforms 5 & 6 and the up slow GWR platform 4. There is a photo of the original DR train shed and footbrige in the LT Museum Collection here. http://www.ltmcollection.org/photos/photo/photo.html?_IXMAXHITS_=1&_IXSR_=OBiA9lXzGON&IXsummary=results/results&IXsearch=Ealing%20Broadway&_IXFIRST_=19 Nowadays you can reach two of the District Line platforms 7 & 8 from the rest of the station at platform level but the far platform (9) only via the footbridge. The station as a whole is frankly a complete mess and is due for significant revision with CrossRail but the original District Railway station within it is actually fairly complete.

As someone said on this thread about two years ago, we all took lot of photos of steam and largely ignored diesels and particularly DMUs but we even more rarely took photos of the rest of the railway except as background to the endless front three quarter views of locomotives, film was after all expensive. For French railways one of the best sources of other photos have been those taken for the weekly Vie du Rail (railway life) magazine which was aimed at cheminots and their families rather than enthusiasts (it included TV listings, recipes and fashion) so had a lot more photos of rail workers doing their jobs and useful images like traders loading their carts in the goods yards or crowds of pasengers. Vie du Rail stil exists, though it's changed somewhat, and publishes coffee table books of its photos though most of these do tend to emphasise trains but was there ever an equivalent publication in Britain that would provide that sort of thing and might still hold a photo archive somewhere? I think the equivalent anachronistic looking image from SNCF was a steam loco hauling a prestige train made up entirely from "Inox", i.e. stainless steel, coaches but they arrived a lot earlier and steam disappeared rather later than in Britain. Apart from Wagons Lits you sort of expect a European steam loco to be at the head of a line of dark green coaches and I rather suspect that the more modern and brighter paint schemes appeared because carriages were not having a constant stream of coal dust, oil and ash dumped on them.

I hope I'm not opening a can of worms here but, since both use a nominal gauge of16.5mm and, so far as I know, similar wheel profiles and B to Bs on most proprietary vehicles, is there any reason why I shouldn't use 4-SF rail standards for 1:87 scale? This struck me yesterday when I was investigating some ancient Pecoway FB and more modern SMP bullhead points built to BRMSB specs (whatever they were at that time). Fairly modern European H0 stock that does show some wheel drop through modern Streamline points passed over them far more smoothly presumably thanks to the narrower crossing clearances. Obviously the sleeper dimensions are different but the critical rail dimensions should surely be the same. I'm not by the way suggesting the use of NMRA's HO standards, it's H0 I'm thinking of not American HO.

Hi Ian So far the comparisons I've made with relatively recent examples indicate a far greater degree of consistency than I'd expected. For instance, I've just stacked six assorted (left right and code 100 & 75) large radius points on top of one another and they line up perfectly. as do the divergence angles of a mixture of all three radii. There have been changes in manufacturing over the past fifty years or more and If you use second hand points made some time ago and possibly a bit distorted in service then there probably will be differences. However, anything reasonably new and straight out of the box does seems to be spot on with their full size planning templates (something that I'm not aware any other manufacturer provides). I've also planned out trackwork using XtrkCad and AnyRail and not noticed any real differences when setting them out physically.

Hi David The two points in the lowest picture in post 31 are small and medium but the scan of the frog end in the first two images are of the same large radius point with lines added to the second image to clarify the curvature. I never suggested that the frog end of the large radius point WAS the same as the small and medium, quite the opposite in fact. What makes comparing all three of them not apples and aubergines is that the large radius ends up with exactly the same final divergence angle as the small and medium but uses a curved crossing and curved rails beyond the nose to achieve that. I think that does have some effect on the movement of vehicles passing over pointwork. You were asking for a scan of the code 75 large radius point and I've now found that I do have a couple of them so here they are. The timbering and overall geometry is identical with the Code 100 equivalent. The crossing gaps (though not the check rail gaps) appear to be slightly finer with code 75 but that may be an optical illusoon because when I've actually measured them I've been able to find very little actual difference and they seems to be using a 1.25 mm gap

David Your small and medium radius points appear to be from different periods and are both fairly old and from a time when the crossing clearances were far greater than they are now (I've got a few of those in the planning box and the crossings/frogs look horrible) You should also be aware that on old points, especially if they'e been bashed around a bit, the stock rails can creep a little and that, possibly combined with slight manufacturing differences may explain why you're getting kinks on straight crossovers. Current production is completely in line with the printable templates they offer so I'd suggest that rather than just looking at the spec. sheets you print those off and compare the older points you've got with them. The large radius point I scanned for post 31 was actually a Code 100 electrofrog but it did confirm what I already knew about the shallower frog and the curved rail beyond it. I don't have a code 75 large radius point but For all three radii Peco use the same base mouldings for both rail sizes so only the rail section, possibly the crossing clearance and the height of the plastic check rails are different. To check that I've just printed off the code 75 large radius template and laid a code 100 point over it and it lines up perfectly. Apart from those for the 83 line, the templates on Peco's site are scans of actual production items and their mass production now seems to be very consistent with the same final divergence angles. If you're using older examples to make crossovers and they're not lining up properly I'd suggest checking the stock rail position and if necesssary a few strokes of the file to square them up. You'll need to cut the rail ends anyway if you want to create a narrower six foot way (2 metre way nowadays) between parallel tracks.

Hi David Despite the Peco template I half convinced myself that a Peco large radius turnout I was looking at last night had straight rails from the crossing V to the heel. When I put it on the scanner and blew up my own image I was easily able to detect the curvature. You should be able to see the slight curvature on the oriignal image but drawing a straight line along the gauge corner should make it clearer. measuring the crossing angle from this with a protractor gave about 9 1/2 degrees and a final divergence angle of 12 degrees. I also managed to half convince myself by eye that there was a slight curvature in the point rail of a couple of Code 75 medium points but this was an optical illusion. I've been looking at several small and medium radius points and though there are slight differences between those manufactured at different times, those from about the same time are identical from the throat to the heel end as this scan of two code 75 points of similar age should show . If you look closely at Streamline points you'll also notice a surpisingly large commonality of components. On these two points everything including the first few timbers, apart of course from the curvature and position of the diverging switch and stock rails, is identical from the throat end to just before the loose heel (where the switch rails are hinged) as is everything from the diverging end to the crossing (frog) throat, it's in the middle that they differ. By the way. looking at your collection of old points I too have a box of these I use for trying out track plans (and for reminding myself not to use slips !!). Don't assume that they're as they were originally supplied.

Comparing some of mine I can't see any difference apart from the rail section. Apart from the plastic check rails, the sleeper mouldings also appears to be identical. The only other difference I can find is that the wipers welded to the code 100 switch blades to improve electrical contact are missing in code 75. Peco presumably assume (or have found) that modellers choosing code 75 are advanced enough to switch frog polarity. That applies to simple turnouts but the code 75 three way point is asymetrical so different from Code 100. Peco's templates for Streamline are photographic or possibly scanned images of the relevant track items; that does show a difference between code 100 and 75 and the termplates ARE different. The 83 line templates are drawings rather than actual images so presumably were prepared before production items were available. David: The large radius points are curved beyond the frog though I had to scan one and print out the enlarged frog end to see it clearly. Martin's figures are correct, the angle at the V is about 9 1/2 degrees and the final divergence angle is 12 degrees. The short and medium turnouts are straight between the V and the end and the geometry of that end of them is identical.