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Post by ejparrott on Jul 21, 2021 15:51:54 GMT
Look at it another way...if you've only got a little engine, you won't get asked to wear it out hauling loads of passengers.....
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Post by Deleted on Jul 21, 2021 16:08:26 GMT
Hi William
I can't help with your question 'per se' but will pass on about an interesting article I read some time ago re Belpaire boiler making vs round-topped boilers. Like you, I thought and in fact, had been told that the belpaire boilers ( I should say 'firebox' )as well known on GWR loco's were more challenging to make than round as found on LNER loco's. This was until I read an engineer's report IIRC published in 1904 at one of those hallowed ' Institutions of locomotive engineers' gatherings where it laid out how the most difficult type to make is in fact the round-topped firebox. It did go into great detail as to why this was, IIRC something to do with staying?. What really caught my eye was this was a paper from the GWR? back to model making, I suspect that for models the belpaire is indeed more challenging to make.
Pete
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JonL
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Post by JonL on Jul 21, 2021 19:06:38 GMT
Look at it another way...if you've only got a little engine, you won't get asked to wear it out hauling loads of passengers..... I wouldn't mind that, it's one of the reason I think I'd like a larger engine!
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Gary L
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Post by Gary L on Jul 21, 2021 19:41:27 GMT
Hi William I can't help with your question 'per se' but will pass on about an interesting article I read some time ago re Belpaire boiler making vs round-topped boilers. Like you, I thought and in fact, had been told that the belpaire boilers ( I should say 'firebox' )as well known on GWR loco's were more challenging to make than round as found on LNER loco's. This was until I read an engineer's report IIRC published in 1904 at one of those hallowed ' Institutions of locomotive engineers' gatherings where it laid out how the most difficult type to make is in fact the round-topped firebox. It did go into great detail as to why this was, IIRC something to do with staying?. What really caught my eye was this was a paper from the GWR? back to model making, I suspect that for models the belpaire is indeed more challenging to make. Pete Hi Pete You are right of course. The Belpaire design is predicated on the stays always being at right-angles to the plates, therefore there are no tricky oblique stresses to deal with, and the boiler should go for longer between overhauls. This was Churchward’s main justification for adopting it, with greater steam space being a subsidiary advantage. Of course in full-size, the throatplate involved costly press tools, but the cost was spread over hundreds of boilers. The same pros and cons apply in model form, but the making of the throatplate looms relatively much larger, as they tend to be one-offs. My limited experience with both sorts is that the extra steam space in a GWR type Belpaire is worth the additional expense/trouble. Others are free to disagree. Gary
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Post by Deleted on Jul 21, 2021 19:58:24 GMT
Thanks for the explanation Gary...the paper did go into a lot of detail which escapes me now, thanks for the better insight.
Regards
Pete
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Post by osiris09 on Jul 21, 2021 21:31:00 GMT
I am definitely in the camp of build something you like. For me I enjoying the building and toodling around with my kids at the track. I hate pulling passengers and only do it to help out the club. I'm not worried about huge loads and would rather a consist of scale rolling stock to people.
I have a range of sizes myself from 2.5" through to 5". Currently i'm building a 2.5" Childs 4F by Curly for my oldest son, as well as rebuilding a Pamela and a Spring Bok. My main loco is a Simplex and it will happily pull a ton behind at the local if required but i try not to do it. Because i dislike the weight of the bigger locos i am moving down the scales. I have no issue moving the big locos, im still in my 30's and have a hydraulic lift at home, but i just find them cumbersome.
Apart from knowing what you really want to build, decide if you care about towing big loads. Pulling my kids and sharing that time with them is all i need to be happy. And you don't have to limit yourself to one scale. Having a stable of locos just lets you choose something that suits the day :-)
Just a thought with SR locos. The 3.5" Pamela was LBSC's vision of the rebuilt Bulleid Pacific's prior to them actually being rebuilt. Mine has been altered to take a 3rd cylinder with conjugated valve gear and also has the spam can look of the un rebuilt style so it might be something to look at and modify or customise to suit you. I have the building notes from ME that i would happily share with you if wanted. There is also someone in the UK doing the boxpok wheel castings in 3.5" that look really nice.
Just my musings anyway. Jeff
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Post by William A on Jul 22, 2021 10:37:41 GMT
I think it's fair to say that without Beech Hurst and the Sussex Miniature Locomotive Society in such close proximity I would continue to build in 2-1/2" without further consideration. However the availabilty of a large, friendly, and supportive club with a large permanent 5" gauge track, as well as a second ME club with a portable 5" track in such close proximity definitely opens up that possibility. There is a proviso (obviously) that whatever I build in 5" must be suitable for passenger hauling on the BH track - otherwise I may as well just stick with 2.5". I have considered smaller 0-6-0T's like Pansy and Boxhill, but discounted them out of hand. Is it worth reconsidering? Along those lines I have been browsing designs which have drawings and castings and come across one I'd not really paid attention to before - the Martin Evans 'Super Claud'. As a Psuedo-Edwardian 4-4-0 with a straight footplate, swooping splashers and an attractive potential livery in the GER Prussian Blue - is it worth looking into?
My eyes keep glancing covetously on larger locomotives like the GWR 4700s, LNER P2's and the LMS Black Fives. Please someone convince me those are terrible ideas.
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robmort
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Post by robmort on Jul 22, 2021 11:59:38 GMT
Hi Pete You are right of course. The Belpaire design is predicated on the stays always being at right-angles to the plates, therefore there are no tricky oblique stresses to deal with, and the boiler should go for longer between overhauls. This was Churchward’s main justification for adopting it, with greater steam space being a subsidiary advantage. Of course in full-size, the throatplate involved costly press tools, but the cost was spread over hundreds of boilers. The same pros and cons apply in model form, but the making of the throatplate looms relatively much larger, as they tend to be one-offs. My limited experience with both sorts is that the extra steam space in a GWR type Belpaire is worth the additional expense/trouble. Others are free to disagree. Gary In models the steam space is irrelevant as steam is created instantaneously into whatever space there is when the pressure drops slightly as the regulator is opened. I don't think the Belpaire design is worth the trouble in models as the more complex twin firebox-to-barrel plates and joints are devils to make accurately and seal after brazing. So better to make a round-top boiler with the correct outer casing.
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dscott
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Post by dscott on Jul 23, 2021 0:06:29 GMT
The Super Claud elegant and most models can be built. But remembering that the Drawings were rushed to meet deadlines of the Magazine. My elegant 2-4-0s are the Asia but not to the drawings supplied by Reeves. These were altered so that they could sell more castings. Yes and so few have been built over the years. Many stopped.
Again the Black Five is a wonderful model and owners love them. Home built ones that is. I dabble once in a while or when a machine is set up making similar stuff. Again a tender kit is ready for a quick build.
For shear ease of moving and Passenger hauling a Don Young Hunslet in 5 inch Narrow Gauge is hard to beat. I have been doing the regulator for the Western Steam Boiler on ours all week. First some Design work. Find the bits of Bronze and make to sizes and tap various holes 4 BA and 6 BA in which the taps survived. Working round the boiler openings can be a bit tricky.
David and Lily.
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Gary L
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Post by Gary L on Jul 23, 2021 0:22:27 GMT
Hi Pete You are right of course. The Belpaire design is predicated on the stays always being at right-angles to the plates, therefore there are no tricky oblique stresses to deal with, and the boiler should go for longer between overhauls. This was Churchward’s main justification for adopting it, with greater steam space being a subsidiary advantage. Of course in full-size, the throatplate involved costly press tools, but the cost was spread over hundreds of boilers. The same pros and cons apply in model form, but the making of the throatplate looms relatively much larger, as they tend to be one-offs. My limited experience with both sorts is that the extra steam space in a GWR type Belpaire is worth the additional expense/trouble. Others are free to disagree. Gary In models the steam space is irrelevant as steam is created instantaneously into whatever space there is when the pressure drops slightly as the regulator is opened. Exactly. Though you should perhaps explain why that is irrelevant in a model but not in full-size. Except let's not, because the argument raged in full-size too- clearly Gresley (to name but one) had the opposite opinion to Churchward, but that of course just demonstrates how Gresley -fine engineer though he was- was sometimes sadly misguided And I say ' exactly', because it is in steam creation that (IME) the Belpaire has an advantage, precisely because of " whatever space there is" -or the lack of it! As you put more water into a round-top boiler, the evaporation area in the best (hottest) location over the firebox reduces rapidly as the water level approaches the boiler crown. In a Belpaire the evaporating area remains much the same until the boiler is practically full. This leads to faster recovery of steam used, irrespective of water level; or more 'reserve space' as the full-size engineers sometimes put it. If you are able to control your water level so it never varies, this is might not matter. If you are a newbie driver, I think you will find it does, and the Belpaire is more forgiving. Clearly therefore your concluding paragraph will only be true if you are of the Gresley school, and you make your own boilers and you haven't mastered the Belpaire construction... I wouldn't dream of making my own boiler, so I can loftily disregard the complexity of Belpaire firebox construction! There are enough expert boilermakers out there to relieve me of such concerns! So to disguise a round-top boiler as a Belpaire seems, from my entirely biassed and partial perspective, to be a sad case of dressing mutton up as lamb, spoiling the ship for a ha'porth of tar, or any one of several other clichés. But the great thing is, you are free to disagree, even if, like Gresley, you are wrong!
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dscott
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Post by dscott on Jul 23, 2021 0:52:32 GMT
Was it just me trying to drive a Poly which has very small wheels and a round topped Boiler which also could be bigger. She was not quite right in places and seemed to spread oil all round the track. Our Electric Beast does not slip due to shear weight but it was the poly.
One day we will be able to go head to head with a Jinty up against a Simplex converted to a Fowler complex. Similar size boilers but the Simplex a round top. Simplex cylinders smaller which is one of the reasons for the Super Simplex... Or was it designed only to be built on a Super Seven? The Fowler Complex is incredibly heavy and chunky being of a narrow gauge style.
David and Lily.
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Post by William A on Jul 23, 2021 9:52:10 GMT
spoiling the ship for a ha'porth of tar Gary, thank you so much for your thoughts on this. Very thought provoking - I keep looking at cost and seeing where money can be saved, but I am always overlooking the fact that the time investment required makes iterative cost changes almost moot. And thank you Mr. Dscott for your appraisal of the Superclaud.
I'm still leaning towards the MoK as said, but I figure I may as well ask while I'm still at the point of being able to make a choice - is there any quantum leap of complexity with three-cylinder locomotives? For example, the Martin Evans' "Royal Engineer" unrebuilt Royal Scot.
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JonL
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Post by JonL on Jul 23, 2021 13:16:10 GMT
I don't have a locomotive with inside cylinders but I think I'm glad: it was a job enough getting the timing right (well, right enough for me, the proper engineers on this forum would have it perfect which I haven't achieved yet) on outside cylinders and valve gear when you are a novice.
Anything with cylinders inside the frame is going to give you more work to setup and probably make, that's not to dissuade you, if you want it enough you will find a way.
As I've said before, I'm not an experienced model engineer, but I'm learning.
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Gary L
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Post by Gary L on Jul 23, 2021 14:00:07 GMT
spoiling the ship for a ha'porth of tar Gary, thank you so much for your thoughts on this. Very thought provoking - I keep looking at cost and seeing where money can be saved, but I am always overlooking the fact that the time investment required makes iterative cost changes almost moot. And thank you Mr. Dscott for your appraisal of the Superclaud.
I'm still leaning towards the MoK as said, but I figure I may as well ask while I'm still at the point of being able to make a choice - is there any quantum leap of complexity with three-cylinder locomotives? For example, the Martin Evans' "Royal Engineer" unrebuilt Royal Scot.
I've never owned a loco with inside cylinders, so I'm scarcely qualified to say... except insofar as that was a conscious decision, with reasoning behind it... In the manufacturing technology sense, as required to build it, there is not a huge difference except in two areas. The cylinder casting (whether a single or twin inside cylinder doesn't matter) will be a big lump, because it doubles as a frame stretcher. You need to be sure you will have the equipment to machine it. Second is the crank axle, and it is not the job for a novice, although many experienced machinists have produced satisfactory ones. Maybe not a quantum leap exactly, but both add to the challenge of manufacture. Then you have the assembly and service aspect. An outside-cylindered loco with no inside cylinders has everything hung in the most convenient location to access... and even then, some operations are a bit fiddly. Hide it between the frames, and even small repairs and replacement of parts can require major dismantling. The GWR favoured outside cylinders with inside valve gear for locos bigger than 0-6-0. The argument was that this gave optimum access, because a connecting or coupling rod could be taken off without disturbing the valve gear or its settings. This might have been true, but when you add inside cylinders as well (Stars, Castles and Kings) the superb mechanism became a driver's and fitter's nightmare for even the simplest lubrication tasks. But this wasn't a GWR-only nightmare, because the combination of inside cylinders and inside motion was a common feature on practically every British railway, not least the Southern. Bear in mind that your fingers will have to work in places where a full-size engiineman could insert his whole body. HTH Gary
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JonL
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Post by JonL on Jul 23, 2021 15:22:51 GMT
Gary echos my sentiments exactly, but more eloquently!
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uuu
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your message here...
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Post by uuu on Jul 23, 2021 15:59:44 GMT
Isn't Maid of Kent either inside cylinder, or sometimes inside valve gear, with outside cylinders? So one version requires cranks on the axle, and the other is still awkward for valve setting etc.
So, although the three cylinder will undoubtedly be more complex, it may not be much more so.
Wilf
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Post by William A on Jul 24, 2021 12:42:28 GMT
Thank you Gary and Jon, that does help. Best to keep my head down for a while!
uuu- The Maid is inside slide valves, with either inside or outside cylinders.
For the Maid, the platework modifications I'm positing can be seen highlighted in blue in this picture (the source is the L-class axle loading diagram superimposed over a Maid of Kent drawing):
I included the shortened smokebox just because the it's a distinctive difference in the Maid/L1 and any SECR locomotive. I believe it needs to move in by about 7/8". There's nothing in the smokebox drawings which clashes that I can see - it looks like fresh air until the petticoat pipe for the exhaust.
Having seen this photo - I'm finding it very hard to consider any other loco now...
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Post by steamer5 on Jul 24, 2021 21:43:38 GMT
Hi William, You could always free lance it…….one inside & one outside cylinder……one of our past members was looking at doing something along those lines.
Ok I’ll get my hat……..
Cheers Kerrin
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Post by coniston on Jul 25, 2021 22:36:25 GMT
If you're keen on SR loco's have you looked at Martin Evans Ashford? his take on Maunsell U class. 2-6-0 outside cylinders, belpair firebox and the ones I've seen seem to perform very well.
Chris
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Post by cplmickey on Jul 27, 2021 7:52:01 GMT
I don't think the Belpaire design is worth the trouble in models as the more complex twin firebox-to-barrel plates and joints are devils to make accurately and seal after brazing. So better to make a round-top boiler with the correct outer casing. I've only ever made one round topped boiler so not a great deal of experience of these but I don't remember it being any easier than the belpair boilers I've made. In fact the first boiler I ever made was a 3 1/2 inch Hall made on my own with no experienced guiding hand (didn't know anyone then) and that came out fine. The next one I did was a 5 inch Manor and although larger and heavier needing an assistant for both heating and lifting and I didn't find that a problem either. My assistant was my mate from down the road so no experienced guiding hand there either. I'm no expert but in my opinion the trick is preparation (like most things) and not trying to rush it. My next boiler build will be a Dart so yet another belpair boiler. But this time using laser cut formers which is far preferable to having to make your own from scratch - now that I do find difficult. Ian
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