Doncaster Details

[john coffin]

I guess you have to understand the way early brake gear worked on GNR locomotives. Doncaster had a cross shaft across the frames about 2 feet 0.5 inches behind rear driving wheel, then the lever to the brake actuating screw is about 16 inches behind this cross shaft. The brake screw is then angled forward by about 10 degrees so that it comes through the top front of the bunker where an L shaped arm, similar to those on GNR tenders operates the brake by being turned clock wise or anti clockwise to release. The L handle is angled forward too.

As you have said before it is a pain that old photographers did not take photos from overhead very often, so we cannot be sure from the drawings as to what the arrangement on the top of the bunker is.The drawing shows a half end elevation, which suggests that there is not a safety casing around the
screw gear, but there is small excuse for a tool box to the outside of it. So, you have to assume that they were very careful when loading coal,
and frankly they used not to go fast enough to worry about shaking the coal around. Useful also to know that the coal hole is on the cab floor standard
18 wide round cornered item for GNR.

Other things to take note of, a horizontal regulator with two vertical rods going up to the safety valve levers.

Paul

[drmditch]

Thank you again Paul. I think I can see how to fit the handbrake control now. It needs to be done with care,or it will look like one of those things on a model which are correct but 'look wrong'! Clearly I will have to make the little toolbox as well!

Unfortunately, I've made the coal hole in the bunker about 20" wide - but it is only visible from the side - so I'm not going to worry about the .66mm!

Just to check, is the regulator 'pull-out' or 'rotate'. I'd assumed the former, but mine seems to have gone a little crooked somehow. That is easily straightened however - if I can find the broad-nosed pliers!

Have you been able to see my discussion about the reversing lever ?

It's not fitted yet, so can be scrapped/rebuilt if required.

What a lot of detail to do on such a little engine!

Just goes to show how engineering practice varied. For a Gateshead/Darlington engine I have far more published information, and of course several local examples to go and see!

[john coffin]

regulator is as I said, across the cab pull out,
whilst the reverser is certainly similar to that which you have created.

The joys of an open cab!!!!

Paul

[drmditch]

Thanks again for your help
What a useful institution this forum is!