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Discussion Starter · #1 ·
It is my understanding that all steam locomotive drivers required counterweights to assist in the conversion of linier motion to rotational motion. Some outside frame locomotives had cast or separately applied weights on the wheel itself, some had independent counterweights fixed to the axles outside the frame and some had a mixture of both. Does anyone know of any engineering reason that one method would be prefered over another or why methods would be mixed? The Oahu Railway's Mikados (similar to the D&RGW K-28s) and the two early Baldwin 2-8-0s (#76 & 98) had counterweights outside the frames fixed to the axles at the main rod connection only. The remaing drivers had counterweights on the spokes. All other outside frame OR&L locomotive counterweights were on the spokes. Just wondering why.

Jeff Livingston
Kaneohe, Hawaii
 

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Jeff,
I don't know if this is true or not, but it made since to me. Someone told me, or I read (don't remember which) that the weights acted to counter act some of the stress on the connecting pivot points between the rods and the outside axel. Not sure if I explained it right, but any way, it was sort of like you have the pressure of the rods driving against the connector that was sort of cantelevered off the wheel,,, where is with inside frames all that strees was taken up by the wheel itself.
I figured and probably wrongly so again that the counter weights were reduced on some of the OR&L engines because they were simpled and the connectors weren't subjected to the same amount of force as a compound engine can deliver?
 

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Discussion Starter · #3 ·
Rick,

Good possibility. Stress would appear to be transferred from an outside/separate counterweight to the axle vice the wheel structure. But why would one method be chosen over another or mixed? The only compound locomotives simpled by the OR&L were #22 & #31 and they had counterweights on the wheels only.

Jeff
 

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Jeff and Rick,

The primary purpose of counterweights are to counter the centrifugal forces (rotational) produced by the WEIGHT of the connecting rod(s) and cylinder rod when the locomotive is in motion. The forces of the cylinder rods getting to the wheels is the function of the PIN the rods are connected to. They are unrelated forces relative to the simple / compound cylinder configuration.

Hope that helps.

Bob
 

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Bob,
Thanks, that is what I was trying to say, but couldn't remember exactly how it was phrased, with the exception that I was told (or read) that those same centrifugal forces exerted an unequal amount of stress on one side of the connecting pin and the bearing surfaces. I'm thinking that does not mean the rod connector but the connection to the axel itself.
Also what about Jeff's other question. Why were these weights removed or reduced on some of the other OR&L engines?
 

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Dear Sir, When the coupling rods are fastened to the wheelsets via crankpins then usually the counter balance isn't needed the wheel balance weights counter any inside motion rods, inside cranks for big ends and for sheaves for working the valve system. When the engine has outside frames depending on the top speed the engine will run then the size of the counterbalance weights could be increased and these balances are for the side rods. I have two model 4-4-0 locos with outside frames and balance weights but my 4-2-2 single dosn't seem to need them?
reciprocating was a term we were taught when we were cleaners meaning converting a horizontal back and fore motion to a circular motion
Jim Brodie.
 

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Discussion Starter · #7 ·
Bob, James,

Thanks for the replies. (James, please do not call me Sir. That was a different life). I'm aware of why the counterweights were needed, either wheel mounted or external, but wondering why specifically on outside framed 3 foot narrow gauge locomotives on the OR&L some would be all wheel weights and some mixed external and wheel. There seems to be a common factor in the mixed counterweight locomotives that the single external counterweight is on the axle with the main rod connection and those wheels with only side rod connection have wheel weights. I can see where it might be desirable to get as much weight outside the frame for stability but that doesn't seem to be the reason. At least on the OR&L.

Jeff Livingsotn
Kaneohe, Hawaii
 

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To Jeff, yes Sir I won't forget Sir.
I just noticed your address.! Where were you some eleven years ago when I had ten days holiday at Wiakiki Beach?
regards the mix of balance weights I would need to see a photo as maybe some of these choo choo's had three cylinders?or axle driven feed water pumps.
Me mam said if I couldn't touch me forelock then I had to say Sir and if I didn't do as me mam said she would clag me
Yours ever so humble one of the serfs from the middle of the North Yorkshire Moors.
I jest a bit of humour makes the world go round.
Jim Brodie....potential platform edge white line painter !
 

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Discussion Starter · #9 ·
James,

Eleven years ago and more I was right here in Kaneohe. Why didn't you call? As soon as Shad gets the new picture posting thing going I hope I can get pictures up again. Since the last change I have failed consistantly. Take a look at a K-28 and you'll see that the first, second and fourth axles have counter-weighted wheels and the third axle has an external counterweight. With the exception of some appliance differences and oil rather than coal fuel, the OR&L had four of the same locomotive. The first two Baldwin Consolidations owned by the OR&L dating from 1878 had the same set-up. All the other OR&L locomotives had all counterweighted wheels only. No three cylinder locos except the two Shay's and no axle driven feed water pumps. Since I'm just an old retired Navy guy and not knighted, sir is unnecessary, and how come you didn't drop by during all that time I was in Holy Loch?

Jeff Livingston
Kaneohe, Hawaii
 

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Mr Jeff (Sir) I didn't get to Holy Loch 'cos my working area was from North of the Thames to Edinburgh and from the East and North East coast to about the middle of the country and although I didn't need a passeport to go to Scotland if I took any of their work I might have had a haggis hoyed at me.
I have a cousin who lives in CA he was on Flat tops during his Navy service. I've only ever been skipper on Princess 32 or 38 motor cruisers and that on the Calledonian Canal from Inverness to Banavie.
On our railways our K classes only went up to 5 so unless I know how to open a photo from somewhere I don't know what a K-28 looks like.
More later as Modom is calling..........Jim.
 

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Dear Mr Jeff - Mr Brodie and I come from an era when we were taught that if you had not been personally introduced, then good manners dictated that you call people 'Sir' or 'Mr' when communicating at long distance- as indeed, we are doing so here on this site.

Although not a Yorkshire lass, my mother, too, would, and indeed did, have fetched me a good clag round the ear for forgetting my manners.

You will notice that on MY posts, I do the same as the redoubtable Mr Brodie. :)

I was called 'Sir' for almost twenty years of my military service, and I don't miss it one bit.

tac [formerly Sir, and now nobody at all]
 

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Discussion Starter · #12 ·
My Dear Tac,

Lest you misunderstand, I too was raised in a home where manners mattered and still do. As to being properly introduced, I believe that those of us who frequest these forums do so without the need of formal introduction as we are drawn together by a common interest where age, rank or seniority have no bearing. My aversion to being addressed as "Sir" is based on that belief as I am no better a being than the next. I too was addressed as "Sir" for seventeen of my twenty-seven years of active duty haveing come "up through the ranks" and don't miss it any either. If the tongue-in-cheek exchange regarding the use of the word "sir" lead you to believe that this Colonial did not comprehend the requirements of dignified correspondence I apologise for causing the misunderstanding. Perhaps I would have been better served by responding "Don't call me Sir, I work for a living".

Jeff Livingston
Kaneohe, Hawaii
 

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Dear Gentlemen My tongue in cheek replies are an escape for me used to gentle leg pulling at work sometimes to relax a situation as when I would climb into a loco cab and the driver would be thinking why is he here ? More later Modom needs me....Jim
 

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Sir Brodie,
Where was you when I was in Edinborough in 1975 trying to get work on the NA pipeline? ;)
 

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Discussion Starter · #15 ·
Rick,

If you have a picture handy of #76 or 98 would you post it so Jim can see what I mean about the counterweights? I'll send you a couple also.

Thanks,

Jeff
 

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Dear Richard (Sir) I was instructing at the school of transport at Aldesbrook House GERegion no I was an inspector at Newcastle and very much so involved in the rail150 moving steam engines around towards Shildon and I believe about that time there was that tragic accident when the tunnel collapsed on those poor workmen. We were only working with drivers as far as Berwick and passengers continued by bus.Jim
 

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so we didn't get to Edinburgh for some time.(Richard) Sir I too was never accoladed and not entitled to Sir except when I was company commander which to real soldiers maybe would have regarded it as F Troop! but many of the Southern locomen used to say Guv and Midland men you got your title "Inspector" Scotsman it was a smile you had to earn their respect. In the area where I did my training(19 years) I sometimes got referred to as Pet,back to cranks mechanical not people looking forward to seeing photos of 76 and 98, are these engine numbers or classes? My poncuter can receive canny sized photos as I am on broadband but we in Rosedale East are eleven miles from the GPO sub station so things tend to run rather slow. I also prefer people to type slowly as I am a slow reader.
regards to everyone Jim Brodie...........The James is my Sunday name or if in bother from Modom.
 

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Correct me if I’m wrong, but does an outside frame loco allow for a larger locomotive?

So especially for narrow gauge, the loco were starting to get so big they would have become unstable so having a wider frame allowed for more weight over a larger width.

If you dig my drift???
 

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Primarily, the wider outside frame design allows for wider boilers (more importantly, wider fireboxes). One of the key components to a boiler is the grate area, essentially the size of the fire. The larger the grate area, the more fire, hence more heat, hence more steam. On locomotives where the firebox is located between the frames, the fireboxes had to be quite narrow, thus restricting the size of the firebox. That limited the size of the boiler that it could efficiently heat, which in turn limited the size of the locomotive.

The outside frame design design came before it was common to put trailing trucks on narrow gauge locos (in truth, trailing trucks had just begun to appear on standard gauge locos, too). The trailing truck allowed the wider fireboxes to sit on top of the frame, rather than having to sit between it. This had the same net effect as widening the frame, so locos developed along the two separate paths. The trailing truck was a relatively "late" development because they came about after coal became the dominant fuel. Wood-fired boilers need a much deeper firebox, making it impossible to put an axle beneath it for support.

An outside frame loco really didn't add anything to stability. The rails were still 3' apart regardless of where the frames were. The Uintah inside-frame mallets were every bit as wide as the D&RGW's Ks.

Later,

K
 

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Sirs The GWR in 1899/1902 had 81 2-6-0 standard gauge tender locos with belper fireboxes the locos designed by Mr W Dean lasting until 1949 and also there were 4-4-0 outside framed locos by Dean and Churchward 1899-1910 which lasted until 1951(Bulldogs) and 4-4-0s 1901-1903 one of these called City of Truro and now preserved touched 100mph in1904. I have three models of these 4-4-0s and the Single in 0 scale and my other outside framed loco is a 1 3/4" gauge 0-4-0 named Harriet used to be a spirit burner now converted to Butane by a good friend in Canada and permanently living with him. It kept chewing my platform walls! Although the GWR engines were outside frames their firboxes fitted inbetween no attempt was made for a Whooton type of firebox but the boilers steamed quite well. The GWR engines were also draughted to burn Welsh Steam Coal. Once at Paddington with a driver and Fireman on a Castle Class I felt decidedly uncomfortable as the engines tender was so low sided. being brought up on NER engines we always had high sided tenders......................Jim Brodie
 
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