What are the cylinders for on Merchant Navy class tenders

[Monjac]

I am sure this a really easy question to some but can somebody tell me please, what the cylinders on the tenders of Merhcant Navy, BB Class etc are for.

[Scrapman]

They are to do with the brakes,a lot of the larger Southern locos had them. I think they used vacuum brakes but not too certain about that. Some of the LNER locos had cylinders on there tenders as well. Usually one but certain classes had two. I'm sure somebody out there will come a long with more detail soon.

[PhilH]

They are vacuum reservoirs for the braking system which relies on the difference in pressure between one side of the brake cylinder piston and the other. The reservoir is provided so that there is always a source of vacuum available to operate the system.

[The Stationmaster]

They are vacuum reservoirs for the braking system which relies on the difference in pressure between one side of the brake cylinder piston and the other. The reservoir is provided so that there is always a source of vacuum available to operate the system.

 

 

So it could truly be said that they are there for nothing

 

(I'll get me coat....)

[Tom Bayford]

And on Some Bullieds thers 3 tanks and others there are 4 tanks:unsure:

[Bulleidnutter]

A crude rule of thumb the Lighweights had 3 cylinders and the Merchants had 4 cylinders. But with the amount of tenders Bulleid made for his pacifics that rule may not apply all the time.

[Tom Bayford]

A crude rule of thumb the Lighweights had 3 cylinders and the Merchants had 4 cylinders. But with the amount of tenders Bulleid made for his pacifics that rule may not apply all the time.

 

For instance Manston has 4 on a 4,500 gallon tender and Eddystone has 3 on a 5,250 Gallon tender and some drivers beleive that the 3 larger cylinders fill up quicker and release quicker than the small 4 on the small tender

[Mallard60022]

For instance Manston has 4 on a 4,500 gallon tender and Eddystone has 3 on a 5,250 Gallon tender and some drivers belieive that the 3 larger cylinders fill up quicker and release quicker than the small 4 on the small tender

 

Great fun getting the correct tender for Merchants if renumbering! There were also different covers (or not) for the cylinders

There's plenty of info around on this though so you should get the correct tenders for BBs and WCs as well if that's what you need.

36E