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Post by niels on Nov 20, 2016 9:45:02 GMT
9Fs are the nicest UK locomotives and it is a pity they are not running over Shap. Their long rigid wheelbase is to blame. More than 13000 german 2-10-0 locomotives have had coupled wheel spacing within 10mm of 9F and could go anywhere. Their truck and first driver is/was united in a linkage so that first coupled wheelset can displace 25 mm each side. Crosshead must pass front coupling pin of course so cylinder spacing is 2190mm. 9F was britsh and placed cylinders 2032mm apart to have diameter enough and stay within loading gauge. Bye-bye sidewards flexibility. To be mainlined again an easy solution is to remove the font coupled wheelset,put flanges on drivers and put a boggie up front. Driving on to the now front driving wheelset like Midland Compounds will allow cylinder spacing of 1905mm. Compound 2 or three cylinder is best. The 2 cylinder is my best bet and is a max 22 inch high pressure cylinder on left outside and a max33 inch low pressure between frames. If boiler is angled sligthly lengthwise view from driver side is improved and weigth distributin OK. Lionel Flippance made a phantasy locomotive and won some IMLECs and my scheme will be better. Whats wrong?
Kind regards
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mbrown
Elder Statesman
Posts: 1,713
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Post by mbrown on Nov 20, 2016 19:48:39 GMT
Lionel's loco wasn't exactly a fantasy - it was very closely based on the 2-8-2 design schemed out by Riddles's team prior to opting for the 9F. The various books by E S Cox on the BR Standards explain why the 2-8-2 was put to one side in favour of a 2-10-0 design - the main one was about weight transfer tot he trailing truck under heavy load which would take weight, and adhesion, off the coupled wheels.
So not so much a fantasy, more a "might have been".
Malcolm
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Post by marshall5 on Nov 21, 2016 9:17:41 GMT
Actually, Niels, the 9F's long wheelbase is not the reason why they are banned from Network Rail lines but their flangeless centre driving wheels. In recent years Network Rail have been raising check rails across the system, and where they used to be level with the running rail, they are now several m.m. above it. Consequently there is a perceived risk, that on a curve, the flangeless wheelset will 'climb over' the raised check rail and cause a derailment. There is a long, very long, 'discussion' on the subject over on NatPres. Cheers, Ray.
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Post by niels on Nov 21, 2016 10:35:32 GMT
Lionel's loco wasn't exactly a fantasy - it was very closely based on the 2-8-2 design schemed out by Riddles's team prior to opting for the 9F. The various books by E S Cox on the BR Standards explain why the 2-8-2 was put to one side in favour of a 2-10-0 design - the main one was about weight transfer tot he trailing truck under heavy load which would take weight, and adhesion, off the coupled wheels. So not so much a fantasy, more a "might have been". Malcolm Hello Malcolm I have read all of the COX books many times and I (being 71) play how to do a better job. The 9Fs was mostly the work of mr Jarvis. First nonconventional feature was the balancing scheme that made 90 miles/hour possible. It was up til then common practice to use some fore and aft balance to counter snaking. Mr Cox did it on Clans and Brittanias. Mr Bulleid had modified a Schools class to have none of that and his 4-6-2 has none either. The result is that 5 feet drivers can safely do 90. The next was that a widebox boiler over 5 feet driving wheels can be just as efficient as widebox boilers over 3 feet carrying wheels. If we go back to mr Beames proposed 4-6-0 and 4-8-0 schemes and cancel the Stannier transfer,UK will save a lot of man hours and coal.Pollution and all that. It is just phantasy but I cannot se what UK locomotives actually built after 1935 would have done a better job. Apart from 9Fs. My other phantasy is how to make a better Darjeling locomotive. I bougth a profile publication fifty years ago and have often wondered how to make something better. Piston valves and compounding is the only time possible improvement in my eyes. I recently got a Orenstein and Koppel reprint catalouge from 1910 and there was a picure of a very beautiful 0-6-0 with Klien Lindner axles. I have fallen deeply in love with that design and after some webcrawling I found out it had run the Matheran railway to everybodys satisfaction for 75 years. Thats the design that could have relieved the DHR class Bs . If You want to se the catalouge mail me Your adress and enjoy it a month or two. Do You know what is happening to the Matheran 740? I think I can still manage to make a 3D-CAD model if I can find a drawing.
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Post by niels on Nov 21, 2016 10:47:26 GMT
Actually, Niels, the 9F's long wheelbase is not the reason why they are banned from Network Rail lines but their flangeless centre driving wheels. In recent years Network Rail have been raising check rails across the system, and where they used to be level with the running rail, they are now several m.m. above it. Consequently there is a perceived risk, that on a curve, the flangeless wheelset will 'climb over' the raised check rail and cause a derailment. There is a long, very long, 'discussion' on the subject over on NatPres. Cheers, Ray. Hello Ray and thank You for letting me see the shining light of NatPres. I am gonna enjoy many,manyhours there. And make some noise I think. Can a 9F just have flanges on driving wheels and set records over Shap? There will be at least my ticket money to grab then.
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mbrown
Elder Statesman
Posts: 1,713
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Post by mbrown on Nov 21, 2016 19:58:25 GMT
Thanks Niels,
Coincidentally, I am much more of a Darjeeling fan than a 9F (or any BR Standard) fan! Personally, I am not convinced the Matheran locos could have made a better job of traffic on the DHR than the B Class. The Klein Lindner axle arrangement is great in theory but poses some interesting problems concerning the weighting on each wheel and the general stability of the loco.
The B Class was perfectly suited to the traffic available - and as that tended to decline after WW2, nothing more powerful was needed. There were various attempts to modernise the B Class - mainly to eradicate the need for a crew of 5... In the 1960s, they tried sanding gear and vacuum brakes but these were clearly unsuccessful and it remained more economical (and safer) to rely on additional staff. Then there was the more recent attempt to introduce oil burning which was a ghastly fiasco!
If we go any further discussing the DHR, we ought to start a new thread - but the relevance to the BR Standards is that locos are designed to suit the traffic that either exists or is forecast - a good example of getting this wrong was the LMS Garratt design which could pull trains that were longer than the available track could accommodate in loops etc.
The design of the BR Standards (and the DHR B Class) was determined by commercial considerations - the cheapest loco that could do the job envisaged for it. Fortunately, we model engineers have different constraints and can do as we please!
Malcolm
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Post by niels on Jan 25, 2017 21:27:39 GMT
Still dreaming of mainlining a tired 9F. I call it Viktoria. It never shows connecting rods. The benefit is that it is different; and easy to give front couled axle sidewards flexibility.
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Post by niels on Feb 5, 2017 18:56:53 GMT
A better picture of Viktoria. Mid coupled wheelset have flanges and front coupled wheelset in a Krauss-Helmholtz truck giving tracking not worse than a Pacific. If made in 1935 most future design was superfluous. The knowledge that two cylinder compound cannot be bettered at speed was known 1938(fig 7 page 6). journals.sagepub.com/doi/abs/10.1243/PIME_PROC_1947_156_058_02
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Post by niels on Feb 8, 2017 19:40:03 GMT
A change of drive system for Viktoria. There is nothing like cool crossheads Power classification 9P/10F
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Post by jordanleeds on Feb 14, 2017 5:59:31 GMT
If it ain't broke don't fix it.. 9fs have their place and sadly the mainline isn't it, may have power on tap but your limited on coal and water capacity and the infrastructure is no longer there for servicing locos. The tours that do operate with steam are very much a logistical nightmare in this ever increasingly busy railway. An example of this is on YouTube showing two separate rail tours climbing snap running block on block with each other being followed by a pendilino .less than 5 mins behind.
If ten coupled is your desire you can do no wrong than looking at the lickey banker 0-10-0 affectionate known as big Bertha.
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Post by niels on Feb 14, 2017 9:26:06 GMT
If it ain't broke don't fix it.. 9fs have their place and sadly the mainline isn't it, may have power on tap but your limited on coal and water capacity and the infrastructure is no longer there for servicing locos. The tours that do operate with steam are very much a logistical nightmare in this ever increasingly busy railway. An example of this is on YouTube showing two separate rail tours climbing snap running block on block with each other being followed by a pendilino .less than 5 mins behind. If ten coupled is your desire you can do no wrong than looking at the lickey banker 0-10-0 affectionate known as big Bertha. It is just a mental game to see how much more power could have been made inside british loading gauge. My favourite now is a sligthly altered WD 2-10-0 five inch gauge design. www.gracesguide.co.uk/images/7/73/Er19591009.pdfThe boiler of the WD was as good as the 9F and my inside two cylinder compound scheme would have allowed a fore and aft balance as good as four cylinder french compounds or the A4.
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