Sunday, 25 September 2016

German Forgings...

Great News...! At long last the tender wheel tyre forgings have arrived at Carnforth. After what seemed like endless delays the good news was phoned through from Rileys to Colin Vaughan on the afternoon of Friday 23rd September. Rileys will uplift them on Monday 26th September and hope to complete all fitting and machining by 7th October (estimated). The SRC will arrange transportation to collect the wheels and get them back to Aviemore as quickly and safely as possible. By that time the tender will be on the jacks in the Carriage Shed waiting to get lowered onto its wheels (hurrah...!!).

Meanwhile there is still work going on at Aviemore Shed. One unpleasant job has been to get at the injector shut-off valves inside the tender tank. The tank has a well at its front and deep in that well are set two shut-off valves operated from a pair of short levers on the tender front. The purpose of the valves is to allow the water supply from the tender to the loco to be isolated so that, for example, the tender can be uncoupled from the loco without having to drain the tank down. When 828 was last in operation it was noted that neither shut-off valve was functioning correctly. The valves can only be accessed by physically entering the tank and crawling forward through the tank internal framing to get to the well. After ventilating the tank thoroughly for a long period we made a controlled entry and confirmed that the valve operating rods were intact and functioning. Close examination showed that the valves weren't travelling fully and that some resetting was necessary. The work was carried out successfully by Tommy MacDonald and we are now able to rely on them once again.

The decision to reconnect the Westinghouse Brake Pump and operate it for demonstration purposes meant that we had to be confident that isolating cock on the boiler backhead (faceplate) was in good order. It has been fully stripped down and refurbished and should now provide a reliable means of on / off control for the Pump. By the way, if anyone has a Westinghouse Pump Governor in their attic it would be good to hear if you are willing to donate it for use on CR 828...! The Governor presently fitted to 828 has no internals. It will allow the Pump to be operated but only under manual control and without being connected to an air receiver. 

Our colleagues in the C&W Dept handed over a pair of wooden packing plates for the front buffers and these have been fitted. Because of material restrictions the new ones had to be made in two halves and glued together. They will do the job although they are a little undersized. However, one of our regular Volunteers, Aidan Bell, has very kindly offered to provide us with two fully-sized offcuts of oak that can be used to make another pair of spacers. These are due to be collected on 26th September from Wester Ross and will be machined to fit in the next few days.

The wooden packing plates provided by the C&W Dept. Note that John Greig has commenced repairs to the buffer beam paintwork.. Note also the absence of any inset access hatch on the fall plate (see bottom picture of CR 827..)

Inside the tender tank, Tommy MacDonald checking out the RH injector shut-off valve. The valve is normally protected by the dome-shaped strainer that Tommy has removed and placed on top of the operating rod. It's an awkward place to get to and one place where size really matters...

Close-up of the shut-off valve in the open position. The operating rod lifts and lowers the valve to open or close the flowpath. Interesting to see how much scale has deposited in the well since the tank was recoated at the last heavy overhaul completed in 2010.

Interesting picture borrowed from the Dunbar Collection showing the cab layout of CR 827 while the loco still carried its original boiler. There are quite a few differences from the LMS-pattern boiler fitted to 828. A couple of obvious ones being that the injectors were originally placed closer to the boiler centreline than they now are. In the next picture below of 828 you can see that the Westinghouse steam cock is now positioned inboard of the RH injector whereas 827 has the reverse arrangement. Note also that the cylinder drain cock operating lever was originally placed on the RH side of the cab in the vertical plane whereas on 828 it's on the LH side operated by a horizontal lever

The Westinghouse isolating cock undergoing refurbishment. The valve plug (a tapered cock) is being lapped into its seat using grinding paste to ensure a good metal to metal seal. To the right is the RH Injector with the slacker hose connection at the top. To the left is the RH gauge Glass..

A magnificent picture of CR 827 borrowed from the A.E. Glen collection. This picture dates from 1918. There are some interesting differences between 827 then and 828 now. Note that the fall plate (piano lid) above the front buffer beam has an inset hinged cover to give access to the steamchest lubricator - now long gone from 828 but something that we plan to reinstate if we can acquire or remanufacture the correct lubricator..

No comments:

Post a Comment

Note: only a member of this blog may post a comment.