Blog Archive

Wednesday, May 30, 2018

The NG/G16 Countdown Begins!

With a projected completion date of mid-2019, the race is on to get our re-gauged South African NG/G16 class Garratt assembled and tested. A lot has been happening, so here's a snapshot of progress to date:

Once the cross shafts and the reverser stand were complete, the reach rod brackets and reach rods were overhauled. The existing reach rods have been modified to allow packers to be inserted fore and aft of the reverser stand, making adjustment far simpler.

Below you can see the outer end of the forward cross shaft, and the reach rod extending back towards the reverser stand.

Much of the engine unit lubrication pipework has been run, including oil pots and dividers. Above and below, the inner pony truck centering spring oil lines.

Above, lubrication lines feeding the cylinders installed, along with the draincocks, linkage and operating cylinder.

Below, the engine unit foot plating being installed, and in the background, the tank support timbers fitted to the angle frame.

Above and below, the inner end of the reverser shaft within the boiler cradle stretcher casting, showing the inner live steam ball joint installed.

The boiler has been clad in expanded mesh, before the insulation layer was added, and the steel cladding sheets fitted. The cladding sheets, all laser cut and rolled new, have been sprayed black, ready for the boiler bands and cut-out surround pieces to be fitted.

Below, some of the various pockets which surround the washout plugs and cover transverse stay heads have been sprayed in primer, ready for painting, and will finish the cladding off neatly when fitted.

The firedoor surround, firedoors, and operating lever & linkage has all been refurbished and fitted to the backhead. The backhead corner cladding is the original, repaired as necessary and fitted.

With most of the cladding fitted and sprayed, the boiler was lowered back into the boiler cradle and secured in position.

Work on the smokebox continues, with the fabrication and fitting of the spark arrestor platework, including table plate, and the removable sections to allow access to the tubes and superheater header behind. The smokebox front plate has been fitted and the smokebox door has been machined and will soon be ready for fitting.

Another significant part to be manufactured recently is the Lempor exhaust nozzle. Based on a design by the late Phil Girdlestone, CME of the Alfred County Railway in South Africa, this complex fabrication incorporates the 4 blast nozzles, as well as a separate chamber and nozzles for both the blower and Westinghouse air compressor exhaust.

Finally, on the 24th April, the 2 engine units were rolled up the workshop and positioned next to the boiler cradle, which was craned over and slung between them. This will allow the completion of all the pipework fabrication and, whilst the engine units may have to come out for short periods to manufacture and fit certain parts, it is intended that the locomotive will stay in this state as the build progresses to completion.

Saturday, February 3, 2018

NG/G News For Febuary

Over the past few months, we have been progressing a lot of different tasks, in order to keep the project moving along at a good pace:

  • Installation of the sanding gear on the engine units (above and below) has reached the stage where the engine needs to be assembled before it can progress further.
  • Cowcatchers and stabilisers have been completed and fitted.
  • Exhaust piping on both engine units is complete (above), as are the steam ball joints.
  • Work has been carried out on the fire hole door surround casting, doors and linkages, ready for test fitting.
  • Overhaul of the Westinghouse air compressor is progressing.
  • The rocking grate steam cylinder and operating levers have been completed (above) and attached to the boiler cradle.
  • Brake pipework is being manufactured for both the engine units (above) and the boiler cradle, including the train pipe and piping up of the brake cylinders and main reservoirs.
  • Turbo generator bracket has been fabricated and fitted to the cradle.
  • Hand brake bracket is complete and has been fitted to the boiler cradle (above).
  • Components for the screw reverser have been refurbished or manufactured (above), the stand has been modified to suit the revised cradle frame geometry, and the whole assembly fitted to the cradle.
  • Work continues on the valvegear, with nearly all components overhauled and fitted, including the new die-blocks and lifting links.
  • Triple valve mounting bracket has been manufactured and installed on the boiler cradle (above).
  • The custom designed lifting bracket for the rear of the boiler (above) has been delivered following testing, and has already been used to lift the boiler from the cradle ready to be insulated and clad.
  • Mechanical lubricators have been fitted following overhaul (above), along with atomisers and much of the pipework, and work has commenced on the lubricator drive components.
  • Design work for the cab is complete, and the drawings and being checked prior to placing an order for fabrication.
  • Drawings for the chimney and the fill-in ring that goes inside the cap have been issued, and the machining work is currently underway (above).
  • The ring seals which surround the pivots, preventing the ingress of dust, dirt and moisture, have been manufactured and delivered. Pivot covers and associated parts are being refurbished or manufactured as required.

Sunday, January 7, 2018

Rising From The Mud

The more eagle-eyed reader of Puffing Billy's in-house magazine, 'Narrow Gauge', might have noticed a dramatically photo-shopped representation of Belgrave yard plateau lurking in the centre spread of last September's edition. The photo gave the impression of a clean, dry and level yard!

Sadly, at the time, this didn't reflect reality; the mud, the dirt, the hastily dug drainage channels to empty the puddles of oily water.

However, things can change in a short time, particularly with planning and the right allocation of resources, and thanks to some hard work by Jason Bell and the W&W boys, we now have a nice new concrete hard standing, covering all 3 workshop roads. This includes grid covered surface drains, designed to control run off and ensure a much more pleasant working environment for workshop staff, loco crews, or anyone simply trying to cross from one side of the yard to the other.

Not only that, but the Belgrave locomotive running shed has had new front doors manufactured and fitted. Not before time too...the old ones must have virtually fallen off!

It's All backwards, What's With That?

The discovery of a broken side control spring on G42's hind engine unit was soon followed by the dawning realisation that with the engine facing the 'Down' direction - towards Gembrook, as all our engines do - the workshop wasn't long enough to get the pony truck in question over the drop-pit in the workshop.

This necessitated a stopover at Emerald whilst the loco was  carefully placed on the turntable and turned to face the 'Up' direction. Luckily, at that time, the 2.30 departure from Belgrave terminated at Emerald, giving plenty of time and some added interest from the passengers.

Obviously this was more exciting that we realised, and Social media was a-Twitter with photos and comments from local Puffing Billy fans!

After turning, the loco crew were faced with the rare challenge of not only running "backwards" all the way to Belgrave, but then having to dispose of the Garratt the wrong way round.

Above, a rare photo of G42 - facing the "wrong" direction - poking out from behind the new boiler of NG/G16 129, and below, the pony truck suspended in mid-air over the drop-pit whilst the spring is replaced. 

The new spring awaits fitting (above). Note the design, with one spring inside another; the original spring design and material section would be prohibitively expensive to replicate today, so we have achieved the same result using two springs of different diameters.

Below, Senior driver and G42's biggest fan Graeme Daniel, poses with the Garratt on the turntable at Emerald shortly before backing onto the train for the trip back to Belgrave.

Thursday, December 14, 2017

Carriage Project Part I - Calculations & Concepts

I think it’s safe to say we can skip the why’s and wherefores’! Anyone familiar with Puffing Billy will know that passenger numbers are through the roof and our little trains are struggling to cope with the ever-increasing demand. At the same time, as much as we try and dissuade them, our marketing department insist on jetting off to the next growing overseas market, building relationships with tour operators who send us yet more passengers!

Two years ago, the Rolling Stock Branch, looking ahead as always, published a paper which identifies the current capacity constraints, and when they occur. The report, put together by Rob Reed, a Puffing Billy fireman and engineering student on work experience, details the times when all rolling stock is utilised, and during those times, how often we reach full capacity, as well as various operational ideas to increase capacity without the availability of more carriages.

The remainder of the report involved calculations to try and ascertain the maximum practical carriage length, and how this compared with the existing carriages in terms of capacity, weight and cost. If you consider that every carriage must have two bogies, 2 sets of couplers & draft gear, and 1 Westinghouse combination brake unit, then if you are trying to keep the train weight down whilst maximising passenger accommodation, you would try to make your cars as long as possible.

The cost of all these parts in comparison to the total cost of a carriage is also considerable, so there are several potential benefits to an increased length.

At this point is should be mentioned that, whilst reducing weight is beneficial, losing too much can have a detrimental effect. The Nadal formula, or L/V ratio, relates the lateral force of the flange against the rail to the downward force exerted on the rail by the wheels. If these forces are not considered at the design stage, there may be a tendency for vehicles which are too light to climb the inner face of the rail and come off the track.

So, where did that leave us? The report was issued to management and the Board, with a recommendation that the any new rolling stock be of a standard 11 metre length, some 4 metres longer that the original VR carriages, and giving a seating capacity of 42 passengers.

Our existing wooden bodied NBH carriages weigh somewhere in the region of 5 tons, with a capacity of 28 people, giving a mass per person of 178 kg. An 11 metre carriage with a capacity of 42 passengers would give an approximate mass per person of only 177 kg, despite the change from timber to steel construction.

At this point we were asked to put come concept designs together, based on the previous steel-bodied NBH cars, open carriages being considered the most popular with our passengers. This we duly did, and feedback received was that 11 metres was thought too much of a jump in length from our existing rolling stock, and would look out of place within a consist.

Back to the drawing board – or 3D CAD software in this case – and the result was a 9-metre carriage, this being the same length as our existing extended NBH carriages, 51 & 52, with seating for 34. An NBHC variation was included, combining an NBH with a guards compartment and wheelchair accommodation.

Various options were put forward at the concept stage but not incorporated into the final design, including:
  • Two seating options, the first with longitudinal bench seats as per the existing cars, and the second with 2+1 transverse seating and end doors to allow for walk-through functionality. The walk-through option would allow for future inclusion of food and drink service on the trains, access to toilets, and maybe even a buffet or bar car. It was also considered advantageous to make access to seating easier, particularly for people with reduced mobility. 2 + 1 seating would negate the need for squeezing along the narrow gap in front of a bench seat already occupied with adults, kids, bags etc.
  • End windows, which you might have picked up from the images, were originally just added to the disabled access end of the proposed NBHC type carriages. It was envisaged that these combined guards/disabled access vehicles would operate with the guards compartment on the in-board end, creating the effect of an observation end, and hopefully a much-improved visual experience for our disabled visitors.
  • In a further iteration, and for consistency, these end windows were added to both ends of the NBH and NBHC type vehicles, with a view to increasing passenger security and safety. Whilst we can’t have a conductor in every carriage, guards and conductors must be as vigilant as possible, and these end windows would potentially allow staff to keep a better eye out along the train.

As part of the Rolling Stock Branch project control process, all groups and individuals considered to be stakeholders in the project were consulted, including the management team, Emerald Tourist Railway Board, Passenger Operations, Traffic Branch Committee, Puffing Billy Preservation Society Executive Committee, and the Heritage Advisory Committee.

Several consultation meetings collected much useful feedback which was taken into consideration as the concept design was firmed up into a final iteration. In particular, much discussion surrounded the layout of the guards compartments in the NBHC, seat layout and design, access and egress issues, and, most importantly, classification and numbering!

After many months of work, the Emerald Tourist Railway Board approved the detailed design, costing and manufacture of 12 new passenger carriages, 8 to be of the NBH type, and 4 to be of the NBHC type, all mounted on a standardised, light-weight 9 metre underframe and newly manufactured 'Fox' type bogies.

To be numbered 24 to 31, the new NBH carriages will weight approximately 6400 kg, and accommodate 34 passengers, giving a mass per passenger of about 188 kg.

The 4 new NBHC carriages will be numbered 1 to 4, and have an approximate mass of 6650 kg. With a capacity of 24 people, or 12 and 6 wheelchairs, this gives a mass per person of roughly 275 kg.

General Arrangement - NBH Class Carriage

Floor Plan - NBH Class Carriage

General Arrangement - NBHC Class Carriage

Floor Plan - NBHC Class Carriage

Part II - Coming Soon!