"Not to be used south of Crewe".

[kevinlms]

2 hours ago, LMS2968 said:

To be fair, designing an entire loco around the distance between adjacent water columns, where two where provided, would be asking a lot from the drawing office. There was a balance pipe between the front and rear tanks to allow the water taken at one end to fill the tank at the other end simultaneously. A more realistic criticism was that this pipe was of too small a bore so the water took and excessively long time to settle. 

 

You also need to consider that two spaced columns were provided for double headed trains with two engines, and two drivers and two firemen, one pair to each column. With only a single crew available, two columns held little or no advantage.

I don't disagree with most of what you said, but the LMS Garratt's were built in 2 batches. An initial 3 and then 3 years later an additional 30 - the largest single order for any Garratt loco.

The LMS COULD have fixed some minor issues, based on 3 years experience, but the only real change made was in the design of the bunker.

It would have been logical, to have fixed the pipe bore between the two tanks. This would have made balancing the water easier, or save moving the loco up.

[LMS2968]

Again, I don't disagree with what you say, but the balancing pipes were the least of the Garratt's problems!

[kevinlms]

3 minutes ago, LMS2968 said:

Again, I don't disagree with what you say, but the balancing pipes were the least of the Garratt's problems!

Yes BP produced an ad, promoting the fact that it was the biggest single order for the 30. Then after that, it mysteriously was forgotten!

[LMS2968]

[Wickham Green too]

6 hours ago, LMS2968 said:

To be fair, designing an entire loco around the distance between adjacent water columns, where two where provided, would be asking a lot from the drawing office. ... 

Looking at the drawing of an LMS Garratt, it's clear that the leading tank filler is at the rear of the tank - as close as possible to the rear tank ............ it wouldn't have been difficult to put fillers for the rear tank either side of the ( original ) bunker to suit the water columns at 50' or whatever apart ( a 4F is about 52' long ) - though without, therefore, much 'swing' to the  crane the driver would have to stop pretty accurately.

 

As for the balancing pipe - presumably it was intended that this would be adequately sized when picking water up from a trough ... at front end only. [ Did they go fast enough ? ]

[LMS2968]

I understand that water could be picked up successfully at 20 m.p.h. so yes, they could go fast enough.

[Michael Hodgson]

3 hours ago, LMS2968 said:

I understand that water could be picked up successfully at 20 m.p.h. so yes, they could go fast enough.

Wouldn't have been much use to the LNER Garratt though - unless they also designed an inclined water trough.

[Wickham Green too]

Probably couldn't find a suitable source of inclined water !

[kevinlms]

12 hours ago, Wickham Green too said:

Probably couldn't find a suitable source of inclined water !

They did, but couldn't work out how to keep it evenly spread. For some reason, it kept running out the lower end!