Monday, 28 November 2016

Back Braking....

The activity during the last week has mainly been on the loco steam brake. With the assistance of Tommy MacDonald, Calum Titley and Roddie McRae the very heavy and awkward brake assembly was lifted back into place and bolted up. The linkages were then reconnected and adjusted. The new grease lubrication points were charged with grease. We will hopefully now have a steam brake that contributes a bit more to the stopping power of the loco than at any time since her British Railways days..

With the brake completed I was able to have a look at a couple of steam leaks in the cab. These have been attended to and will be checked out when we next steam the loco.

Colin Vaughan is starting to press Rileys for news on the replacement tender tyre forgings which are now becoming overdue relative to the six week delivery lead time that was quoted when they were ordered...

The heavy lifting squad - Tommy MacDonald, Calum Titley and Roddie McRae relaxing after getting the loco brake cylinder back into place under the dragbox..

To help take the weight of the brake cylinder (approx 200 kg) we used the ubiquitous blue rope - a turn around the trailing axle and then over a convenient bar placed across the cab leanouts made quite a difference..

The steam brake cylinder fully back in place and all pipework reconnected and ready for a steam test...

The brakes adjusted....

The loco waits behind closed doors on one of these beautiful cold and very sunny late Autumn days in Strathspey..

Waiting in the shadows.....

Something that I hope we'll see again in 2017... CR828 and 46512 on a special double headed working for the benefit of the Strathspey Railway members and supporters..

Saturday, 19 November 2016

Taking a brake...

 It's been a busy time with 828 since the last update on the blog. We've had her in steam twice to check out various repairs and also had the Trustees of the CR828 Trust, the legal owners of the loco, at Aviemore for their AGM. Not all of the Trustees could make the journey to the far North and those who did expressed their satisfaction with the work that has been carried out on the loco. At the AGM Ian Stanworth, SRA Chairman, was elected as a Trustee. The SRA has been very consistent over many years in providing financial support to 828 and it seems fitting that the SRA Chairman should be a Trustee. 

John Greig has been making and fitting more new and improved worsted trimmings to the motion parts - he has made them to give an increased rate of oil flow to ensure adequate lubrication for the new bearings on the big ends and eccentrics. Once the loco is run-in the flow can be reduced.

The oak planks donated by the National Trust for Scotland courtesy of Aidan Bell at Inverewe Gardens have been marked out and cut roughly to size as the new wooden packing for the front buffers. Final machining is being undertaken by a neighbour of Keith Holyland in Auldearn. The finished spacers will be fitted shortly.

Some time was spent recently adjusting the loco brakes. It can be fairly said that the loco steam brakes have never contributed a great deal to the stopping power of the engine. The tender steam brake has always seemed to provide most of the brake power. I discussed this several years back with the late William Peaston who had driven members of the 812 Class in BR days when he was a Driver at Greenock Ladyburn Shed. His recollection was that the steam-braked locos were better 'stoppers' than the Westinghouse air braked versions. He was therefore surprised that we found 828 to be a poor 'stopper'. We may have uncovered the reason for this. BR removed the Westinghouse air brakes from 828 in the mid-1950s and fitted the steam brake that we have today. When the loco was steamed last week it was partly to test the brake following adjustment. The result was disappointing; there was a great deal of leakage past the brake piston and the brakes were very slow to release. A decision was therefore taken to remove the brake cylinder from under the dragbox and strip it for a full examination. This revealed that one of the two piston rings was too tight in the cylinder due to lack of ring gap clearance. The gap was adjusted and the piston, which had been very difficult to move, became a very good sliding fit in the cylinder. We also found that the bellcrank lever that transmits the force from the brake piston to the brake pull rods had seized on its pivot pin and required excessive force to make it move. With something of a struggle the pin was freed and the bellcrank removed. With everything cleaned up we decided to fit grease injection points to the bushings to prevent this problem recurring. The Caley had provided an oil hole in the bellcrank but this was found plugged with coal dust and no oil had penetrated to the pin for a long time..

Colin Vaughan has been pressing Rileys for an update on delivery of the correctly sized tender tyres. As before, the order has to be placed via West Coast Railway Company Ltd. Rileys have been pressing them for an update but none is available thus far. Hopefully we will hear something before the end of November..

Looking smart outside the Shed and getting ready for another steam test on 11th November..

In flight...! Nathan Lightowler demonstrates 828 in action for the CR828 Trustees at their AGM on 12th November..

CR828 Trust Chairman, Jim Spy climbs aboard the Trust's loco on 12th November. Some other guy gets into the picture too..

John Greig fitting new trimmings to the RH Big End on 11th November..

Roddie McRae with a wheelbarrow load of oak planks and one of the old spacers for the front buffers..

Marking out for cutting the oak to size..

Roddie McRae putting a coat of paint on the new LH Driving Hornblock..

The loco steam brake cylinder - bolted to the underside of the dragbox. Because of the geometry of the brake pull rods the piston moves upwards to apply the brakes. This is a reversal of the practice adopted by the LMS and BR where the brake piston pushes downwards to apply the brakes..

It's a heavy lump...! Roddie McRae removes the nuts while Colin Vaughan and Calum Titley take the weight of the cylinder..

Safely landed on the Shed floor we can see the piston peeping coyly out of the cylinder and very reluctant to move..

Colin Vaughan admires the upturned cylinder...

Piston stripped for inspection on the bench in the Shed fitting shop..

Reassembled with both piston rings now having the same gap clearance when fitted in the cylinder

Colin Vaughan applying some heat to help remove the brake bellcrank pivot pin..

The pivot pin driven almost completely out...

The refurbished brake cylinder awaiting refitting to the loco..

Brake piston rod top-end rebushed by Nathan Lightowler..

Tapping out the bellcrank for a grease nipple to assure correct lubrication of the pivot pin.

Job done - grease nipples fitted to the bellcrank and the brake piston rod pin..

Under the loco drilling and tapping the bellcrank hanger bushes for grease nipples..

With the bellcrank removed the hangers (riveted to the loco frames) lie on either side of the brake rigging pull rod. At the top of the picture is the trailing axle and forward of it is the rear of the ashpan..

Bellcrank back in place and lubrication assured...

Low sunlight on a very cold Autumn day (18th November) catches 828 as she watches 46512 outside in the Shed yard getting ready for a test run....

Sunday, 30 October 2016

Maybe Next Month....

The waiting continues but the work hasn't stopped. While we wait for the replacement tyres to arrive with Ian Riley there is an opportunity to get on with other work on the loco and the tender.

On the tender we've been able to refit the brake hangers and fit new brake blocks. This should have been a very straightforward job. Where it became awkward was when we found that the new brake block castings didn't quite fit the hangers. The blocks have a clevis cast into them into which the hanger should slide and then the securing pin pushed through and locked with a split pin. Bob Edwards, the man from the RPSI, drilled the pin holes through the new blocks and we set about fitting the first one and that was when we found the problem. The solution adopted was to remove all six hangers and skim them by about 0.060" in the milling machine. This should have been pretty straightforward but the Caley (or the LMS) chose to make the hangers from a very hard grade of steel. Using Nathan Lightowler's best cutting head and a lot of new tips we finally managed to get a fit for all of the hangers and the new brake blocks are all safely fitted...

On the loco we took the opportunity to strip the old paint off of the smokebox and the chimney so that they can be repainted with high temperature gloss black. This was done using a needlegun. The chimney needed some filling to recover the elegant curve of the Macintosh design. The end result looks very nice particularly after the smokebox door was repainted.

The smokebox door closure mechanism has not looked completely satisfactory for some time so we decided to try and improve it. The problem lay in the tendency for the locking screw to droop below the boiler centreline and give a rather untidy appearance when viewed from the side of the loco. Correcting this involved some remedial work on the "dart" that pulls the door tight against the internal crossbar inside the smokebox. An improved guide tube was made and fitted and the overall result looks much better.

We hope that the replacement set of tyres will be with Ian Riley before the end of November....

Tender brake block correctly fitted to the RH Leading brake hanger..

Bob Edwards and Nathan Lightowler finding out just how hard is the steel used by the CR for their tender brake hangers. Even Nathan's biggest and best multi-tipped milling cutter struggled to do its job..

Fitting the new springs to the centre axle was easier than renewing the brake blocks...

The smokebox and chimney minus their old paint (the chimney cap didn't need the old paint removed)

Filling the imperfections in the chimney casing and the doorplate rivets..

Rubbing down the filler...

The chimney ready for painting...

Partly painted chimney...

Roddie McRae painting the inside of the smokebox wingplates..

Alan Murphy painting the fallplate (piano lid) that covers the cylinder and steamchest front covers..

Smokebox painting completed but the door lock removed for maintenance..

The "dart" receiving attention..

Job done...! Painting completed and the door lock back in place complete with the famous Caley star..!

Tuesday, 4 October 2016

Sackcloth and Ashes...

Well, what a come down after the previous post. A message on Monday 26th September from the Shed to say that Riley's had collected the tender tyre forgings and found that they are oversize on their inside diameter and can't be fitted to the tender wheels. And why - an incorrect measurement on my part when Riley's asked us to measure the wheel centre diameter after we removed the old tyres back in May. The only way forward is to order another set of forgings from the German supplier and hope that they will be delivered more quickly than the present set. There is also a financial consequence although it may be possible to sell the forgings on to another heritage railway concern... Depending how things go with delivery of the replacement set of forgings we may be able to rewheel the tender and complete the running-in of the loco during November.

On a brighter note I collected a set of sawn oak pieces from the National Trust for Scotland estate at Inverewe Gardens. This kind donation was arranged by Aidan Bell who helps to manage the estate and also finds time to Volunteer at Aviemore Shed. We planned to machine a pair of buffer beam spacer plates from the pieces although I have been subsequently advised by Keith Holyland that they may not be suitable due to the presence of sap wood at the diameter where the bolt holes would be formed...

One piece of good news is the arrival of a new pair of tender springs ordered by the SRC to replace the rather tired existing set on the centre axle.

Hopefully the next update will have more positive news to report...

Aidan Bell, National Trust for Scotland handing over four offcuts of oak from a tree that was undergoing dismantling at Inverewe Gardens

CR828 with the oak offcuts. One of the original spacer plates is perched on top of the pieces..

The new springs for the centre axle on the tender. The buckles will be fully painted and lined out correctly..

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..