Bath Queen Square

[Compound2632]

44 minutes ago, queensquare said:

These  little locos  were underpowered by the 1920s and must have been thrashed at times,

 

Let's be honest about it: they were underpowered by the time the last one rolled off the production line in 1902; the H-boilered version started to appear in Johnson's last year in office. (Larger boiler = more steam but not more tractive effort, though I should check if there was any further increase in boiler pressure from the 160 psi of the last Ms.)

[phil_sutters]

1400 hits - now 1401 - congratulations!

[bill-lobb]

48 minutes ago, Compound2632 said:

 

Let's be honest about it: they were underpowered by the time the last one rolled off the production line in 1902; the H-boilered version started to appear in Johnson's last year in office. (Larger boiler = more steam but not more tractive effort, though I should check if there was any further increase in boiler pressure from the 160 psi of the last Ms.)

I often see comments that class 2 locomotives were underpowered - that includes the 2Ps.  However when the LMS decided in the 1940s to replace their old 4-4-0s and 0-6-0s with mixed traffic 2-6-0s they built 2 designs - 2MT & 4MT. They must have seen plenty of work that a class 2 locomotive could do more economically than a larger one.

 

Bill

[Oldddudders]

Logically no loco is actually underpowered per se - but many locos may be underpowered for the task they are asked to perform, which I infer was the S&D case in question. And the LMS rationale for building 2MT locos was obviously replicated in the 1950s, with BR building 78xxx and 84xxx classes. 

[5944]

1 hour ago, bill-lobb said:

I often see comments that class 2 locomotives were underpowered - that includes the 2Ps.  However when the LMS decided in the 1940s to replace their old 4-4-0s and 0-6-0s with mixed traffic 2-6-0s they built 2 designs - 2MT & 4MT. They must have seen plenty of work that a class 2 locomotive could do more economically than a larger one.

 

Bill

Wasn't a lot of the reason for 2MTs due to weight considerations, rather than minimal power? The thing that confused me is why did BR decide it needed both 2-6-0 and 4-6-0 4MTs, as well as tender and tank versions of 3MTs. 

[DK123GWR]

12 minutes ago, 5944 said:

Wasn't a lot of the reason for 2MTs due to weight considerations, rather than minimal power? The thing that confused me is why did BR decide it needed both 2-6-0 and 4-6-0 4MTs, as well as tender and tank versions of 3MTs. 

If I had to guess (and this is a guess, based on the characteristics of the locos rather than how they were used):

-The driving wheels on the 4-6-0 are 5ft 8, rather than 5ft 3 on the mogul. So the 4-6-0 was perhaps better suited to higher speeds, and the mogul to heavier goods work and faster acceleration.

-The 3MT tender engines have a tender (so larger range) and the 3MT tank engine was a tank engine (so didn't need to be turned). One was probably suitable for long-ish rural branchlines, and the other for suburban work which didn't require a 4MT, or for much shorter branches which lacked the equipment to turn locos.

[Compound2632]

21 minutes ago, 5944 said:

Wasn't a lot of the reason for 2MTs due to weight considerations, rather than minimal power? The thing that confused me is why did BR decide it needed both 2-6-0 and 4-6-0 4MTs, as well as tender and tank versions of 3MTs. 

 

I had rather gathered it had to do with keeping the staff of four locomotive drawing offices occupied!

[t-b-g]

I think people forget sometimes just how many secondary railways there were and how many locos were needed to operate them. Not necessarily branch lines or suburban services, just lines that went from one place to another, through a few other small places, that never warranted any more than a 3 or 4 carriage train. If you look at the LNER, the number of 4 coach sets (Brake 3rd, 3rd, Composite, Brake 3rd) must have outnumbered the ECML express trains many times over.

 

They were worked from pre-grouping days by 0-6-0 or 4-4-0 types (or similar smaller locos) that were sometimes around 60 years old by the 1930s/1940s.

 

As the locos became life expired, the need for replacements led to the more modern smaller types being introduced. Many lines had weight restrictions, small turntables or other restrictions and the bigger and more powerful a loco was, the more expensive to was to build and run.

 

It is easy to look back at 75 years ago and say what we think the railways should have done. None of us were making the decisions than and I would be surprised if we can make a better decision now than they did then other than by the use of big doses of hindsight.

 

 

[Dunsignalling]

On 13/02/2022 at 10:26, bill-lobb said:

I often see comments that class 2 locomotives were underpowered - that includes the 2Ps.  However when the LMS decided in the 1940s to replace their old 4-4-0s and 0-6-0s with mixed traffic 2-6-0s they built 2 designs - 2MT & 4MT. They must have seen plenty of work that a class 2 locomotive could do more economically than a larger one.

 

Bill

It also depends on where in the Class 2 spectrum the loco fits. The Ivatt 2MTs were probably "almost Class 3" and the 4MTs firmly in the upper half of their own bracket (once the double chimneys were removed). There's a lot more than nominal tractive effort involved in a good performing design.

 

The Ivatt tanks seem to have been regarded as pretty much equal to their lacklustre Stanier 3MT predecessors and superior to the Fowler version.

 

The tender 2MTs were generally expected to perform better and handle increased loads over the antiques they replaced. They seldom failed to deliver by all accounts.

 

John

 

 

 

 

Edited February 16, 2022 by Dunsignalling

[Compound2632]

7 hours ago, Compound2632 said:

Let's be honest about it: they were underpowered by the time the last one rolled off the production line in 1902; the H-boilered version started to appear in Johnson's last year in office. (Larger boiler = more steam but not more tractive effort, though I should check if there was any further increase in boiler pressure from the 160 psi of the last Ms.)

 

Checked. The H boilers were pressed to 175 psi, so a significant increase over the last Ms. (Many Ms were built with 150 psi boilers which first came in with the Neilson Goods; earlier Johnson classes were built with 140 psi. I presume that as time went by, the stock of boilers would eventually only consist of 160 psi ones for the remaining engines not rebuilt with H boiler or, eventually, with Belpaire boilers, either as 3F or 2F.

[queensquare]

Structures have replaced locomotives on my fireside bench and the subject matter has moved a lot further west!

 

I want to get these to the stage where I can use them to  demonstrate some painting and finishing techniques at Missenden in a few weeks time. Further progress on these will be over on the North Cornwall thread.

 

Jerry

 

Edited April 2, 2022 by queensquare

[queensquare]

Another work in progress I shall be taking along is bridge No 1 over the Lower Bristol Road. I’ve been asked about building a viaduct - this one has embossed plastic stone abutments, brick paper arches on a ply core and a plate girder which will be either plastic or brass - all on a curve and rising gradient so covers a number of bases!

 

Jerry

 

Edited April 2, 2022 by queensquare

[tapdieuk]

Looking good Jerry.

Are these bridges the last gap before the track is in a continuous run from Queen Square to the Colliery? 

 

Will

[queensquare]

3 hours ago, tapdieuk said:

Looking good Jerry.

Are these bridges the last gap before the track is in a continuous run from Queen Square to the Colliery? 

 

Will

 

Sadly not Will, there are a couple of other smaller bridges to do as well. Most of the trackwork is made it's just a case of laying it, wiring, connecting the point mechanisms........ :-)

 

jerry

 

[Sithlord75]

1 hour ago, queensquare said:

 

Sadly not Will, there are a couple of other smaller bridges to do as well. Most of the trackwork is made it's just a case of laying it, wiring, connecting the point mechanisms........ :-)

 

jerry

 

You've got until June............. 

[queensquare]

7 hours ago, Sithlord75 said:

You've got until June............. 

 

It'll be finished by  June, just not saying which June!

 

Jerry

[richard i]

7 hours ago, queensquare said:

 

It'll be finished by  June, just not saying which June!

 

Jerry

What a kind lady June is. My female friends won’t help me lay track. 

[Argos]

9 hours ago, queensquare said:

 

It'll be finished by  June, just not saying which June!

 

Jerry

In which case can you not be more optimistic and have it done by May? 

[Caley Jim]

1 hour ago, Argos said:

In which case can you not be more optimistic and have it done by May? 

But will May make as good a job of it as June?  

 

Jim

[Compound2632]

14 minutes ago, Caley Jim said:

But will May make as good a job of it as June?  

 

She May do. Get April to lend a hand too.

Edited February 16, 2022 by Compound2632

[St Enodoc]

2 hours ago, Compound2632 said:

 

She May do. Get April to lend a hand too.

Careful...

[Sithlord75]

Having three ladies helping lay track seems to be risky to me.

[Dunsignalling]

9 hours ago, Sithlord75 said:

Having three ladies helping lay track seems to be risky to me.

They might gang up and give you your Marching orders. 

[Oldddudders]

9 hours ago, Sithlord75 said:

Having three ladies helping lay track seems to be risky to me.

Especially since someone once wrote "June is busting out all over"!

[Roger.s]

10 hours ago, Sithlord75 said:

Having three ladies helping lay track seems to be risky to me.

Three of them will delay it until July comes

 

Roger