What's This For?

http://www.talyllyn.co.uk/sites/default/files/imagecache/main/img/No.4.2-djm.jpg

What are the doors on the back of the cab for? Is there not enough space to shovel in coal?

 

I'm more inclined to think that it's so you can use the fire irons and clinker shovel. The Corris engines originally had a large round hole but No 4 has since been modified. Many locos had a smaller hole higher up in the cab back for withdrawing the regulator rod. Hope this answers your question. Ray.

 

It is useful for using the clinker shovel but not necessary. It's quite helpful to keep the cab cool on a down train as No.4 can get hot. No.7 has similar doors too.

 

Is it for sweeping the tubes that are inaccessible at the smokebox end because the blastpipe is in the way?

 

That makes makes sense. (Now it seems obvious.)

I would imagine that opening the doors would make a heck of a lot of difference for the crew. I think No. 3 also has those doors.

 

That could be. They may use a flexible tube cleaner.

 

The tube cleaner is just a normal steel rod with a brush on it.

 

Ah, I see.

 

As Neil has said, they are there to aid shovelling out the fire. The Corris engines ( 3 & 4) originally had circular ones with a plate that fitted over the hole on the inside. When No.3 was rebuilt in the 1960's the rectangular doors were fitted. I seem to remember fitting them but I could be wrong; it was a long time ago. No.4 followed suit at a later date. Again, as Neil said, they were handy on warm days.

 

Thanks for the info!

 

It is a pet hate of mine the doors being open as I think the sight of a pair of legs through a whole in the back of a cab as an engine appears under Wharf bridge is not the best first impression to give customers. Equally I always tried to keep cab windows shut as it improved the image for the passengers. Why spend time polishing if the first thing you are going to do is open so thay are not seen?

I reckon the doors are just a simple hangover from Corris or the early TR days before the cabs were enlarged. In those days they may been needed for crew to use a clinker shovel etc but I cannot remember in recent times seeing anybody use a clinker shovel on 3, 4 0r 7. As you will be aware most just use a the loco's own shovel.