Category Archives: Campaigns

Autumn Engineering Update

Autumn Engineering Update


Welcome to this autumn engineering update from the General Steam Navigation project.  Progress has been made on various engineering fronts on the project over the past few months and with some of our background efforts about to bear fruit we’ll have some brilliant work to share over the coming months.


The boiler tubes are gone! After many months of hard work by our small band of volunteers, the job is done. Work has continued on removing rust from the inside of the firebox, descaling the inside of the boiler, and generally cleaning the inside of the boiler and firebox ahead of a planned inspection later this year. Still to do is sourcing the right tool for removing the thermal-syphon inspection plugs, so that we can wash out the boiler, and then plan the inspection.

Crank axle

Progress with the crank axle has been limited in the past few months; geopolitical events has caused the price of steel to become volatile, after discussions with our friends in the B17 project & A1 Steam Trust, with whom we were planning to place a group order for A4T forgings for the stub axles, we are pausing the ordering process until we have greater certainty over the price. Whilst it is disappointing to not be placing an order for these crucial parts of our locomotive, it feels more prudent to wait, saving us money in the long run. During this self-imposed delay, we are using the time to produce the engineering justification for manufacture of the stub axles in A4T & the sweep webs in 817m40, so that when we are happy with prices, we can proceed.


Work on the frames continues at a good pace with our volunteers working hard to clean up the frames in preparation for assessment of their condition. With over 50 years of grime to remove on the frames its not a particularly glamorous job but is very important and we are extremely grateful to all our hard workers. We have also removed the brake cylinders from the frames as they wont be required for an original condition Merchant Navy. The cylinders will be cleaned up and stored should a rebuilt Bulleid require them in the future.

Sponsorship component of the month

For those that want to make a more tangible contribution towards putting the steam back in General Steam Navigation we have relaunched the ‘Component Sponsorship’ scheme.

Each month the Society will highlight one particular component. The scheme will allow generous sponsors to cover the cost of individual parts that range from few pounds to several thousands.

Our generous sponsors will receive a certificate describing the part sponsored, be named on the roll of honour on this website and gracious thanks from all those who wish to see General Steam Navigation back in operation.

This month we are starting with the steam chest covers for the outside cylinders. The steam chest covers are a relativity simple component to produce being machined from plate steel.  35011 will require 4 of these in total with the covers being fitted to the front and rear of the cylinder on both sides .The cost of these covers are £250 each. For a full list of the currently available component and how to sponsor them please visit the component sponsorship page. 


The question that has been asked a few times, both within our project, and outside it, is why we are considering modifications to the exhaust, especially as Bulleid pacifics had a reputation for being free-steaming, if hungry locomotives. The reason is buried in that last statement. Consider how a steam locomotive, especially its combustion system works: exhausting steam in the smokebox produces a draught, sucking air into the firebox for the coal to burn. How much air the locomotive supplies to the fire will impact its fuel combustion. Too little, and you have rich combustion, which releases a lot of heat from the coal, but at the expense of high fuel consumption. Too much air, and you have overly lean combustion, which is cleaner (less production of carbon monoxide), but it can lead to high fuel consumption as well, as the extra air cools the hot air from the fire, reducing the heat transferred to the water in the boiler, meaning more coal is needed to be burnt to produce the same heat transfer to the steam. The reputation, coupled with data from the Rugby reports, suggests that at most of the steaming rates GSN is likely to operate, the combustion is too rich. The perfect air:fuel mass ratio for stochiometric combustion of coal is approximately 11.2:1. It is normal to supply more air than is necessary, to ensure all of the fuel sees sufficient air, normal practise for combustion of coal is to have approximately 30% extra air, so the ratio becomes 14.6:1. Data from the Rugby reports show the original locomotives ran with a ratio of between 11:1 & 17:1, with drop off in performance for steaming rates above 18,000lb/hr, which is where we can expect to operate. The rebuilt design exhaust was much less variable to incomplete combustion, and had higher air:fuel ratio. The data also suggests that these locomotives need to run with significant excess air, far more than the 30% recommendation. The rebuilt design can actually be seen to be broadly similar to how 71000 operated in BR service, suggesting that we can achieve similar performance with 35011 if we can emulate the performance of 71000s twin Kylchap design. By redesigning the exhaust, we should be able to achieve two things: (1) maintain closer to 50% excess air across the power range, reducing fuel consumption and (2) increase the total flow area of the blast nozzles, reducing the cylinder back pressure.

Working Weekends

Our current plan for working weekends in 2022 is as follows:
15th /16th October
12th /13th November
10th /11th December
14th /15th January 2023
11th /12th February 2023
11th /12th March 2023

As always, any members who would be interested in being involved with the engineering of our project, please do get in touch. Our CME Dr Steve Rapley does need some support on the engineering of this project, especially at the moment with weld design, so if you have any experience in this area, please do get in touch. Similarly, if you have any question or comment on the Engineering report or the engineering in general, please do  get in touch at by email to Dr Steve Rapley here.

To help us achieve our goal of an original condition Merchant Navy we’ll need your help, you are able to support us in many ways if you are not already a Society member you can sign up for membership for currently only £15 per year here, or donate to the Society here, consider sponsoring a component here or even better become a shareholder here.

As always thank your for your continued support

Become a Trailing Truck Transformer

#OnThisDay in 1955 General Steam Navigation entered the Eastleigh works for a heavy intermediate overhaul. It was during these works when her cast trailing truck she was built was changed for the fabricated design she still has. The fabricated design was fitted to the final ten Merchant Navy’s with the first being 35021 New Zealand Line with 35011s being the last remaining example with all fellow surviving Merchant Navy’s having the earlier cast design. The General Steam Navigation Locomotive Restoration Society aims to restore this unique component in 2021.

This is your chance to be part of an exclusive club and aid the overall restoration of General Steam Navigation by becoming a Trailing Truck Transformer.

The Trailing Truck was removed from the frames at the same time as the successful boiler lift on 2nd October. The estimate for the full refurbishment and overhaul of the Trailing Truck by specialist contractors is £15,000.

We are offering a maximum of 30 members the opportunity to purchase a ‘Lot’ for £500. Members are welcome to purchase as many ‘Lots’ as they wish up to the maximum target amount.


Members of the Fund Group would receive a number of benefits including:

  • Certificate of membership of the ‘Trailing Truck Transformers’
  • Name engraved on a suitable brass plaque attached to the refurbished Trailing Truck
  • Regular updates on the refurbishment of the Trailing Truck
  • An invitation to a VIP day at the Swindon and Cricklade Railway to see the completed Trailing Truck once it is returned to the railway.

The work

With the trailing truck now removed from GSN, we have undertaken an assessment of the work that will be required to restore it to mainline running standards. This will involve a full strip down to allow us to understand the condition of the frame metal work, which is likely to require non-destructive testing to determine the soundness of the existing material.

The axle will also require removing, but depending on which contractors we decide to use for the overall work we may need to remove this at Blunsdon to enable it to be sent separately for repair with the wheels being re-profiled; whilst the axle bearings will also need assessing and possibly refurbishing.

The frames will also require sandblasting to remove all the old flaking material and paint, with the corroded sections of the framework and rear platform being cut out and replaced with new material. Finally the framework, axle and wheels will need to be primed, undercoated and painted prior to being re-assembled.

To become a Trailing Truck Transformer see our dedicated page here…

We understand that £500 is a lot of money and for people who wish to support the trailing truck but are unable to join the Trailing Truck Transformers club you can help us by donating to our Wheel Set appeal on our JustGiving page here.

Alternatively you can make a donation however large or small into our newly launched Putting Funds into the Frames campaign here…

Any and all donations would be gratefully appreciated.

35011 General Steam Navigation fund opened for the transportation and tyre profiling of the bogie and trailing truck wheelsets.

On 2nd October 2020, the boiler of Ex-SR Bulleid Merchant Navy Class, 35011 “General Steam Navigation” was successfully lifted from its frames for the first time since 1959 and the separation of the trailing truck from the frames. The General Steam Navigation Locomotive Restoration Society is now seeking funds to help overhaul the front bogie and trailing truck wheelsets.

35011 front bogie at Eastleigh Works 1959

It is  estimated that the trailing truck axle will be machined by a contractor off site in early 2021. This is where we need your help we are fundraising to help cover as much as the cost as possible with the target being set at £3,500.

The unique in preservation fabricated style trailing truck of 35011

Supporters can donate to the cause via the Society’s JustGiving page at

Work on 35011 will now be directed to the restoration of the chassis, trailing truck and the front bogie and further fund-raising campaigns will be launched in due course.

You can help support us in many ways if you are not already a Society member you can sign up for membership for only £12 per year here, or donate to the Society here or even better join us as a shareholder here.

As always thank you for your continued support.

Boiler Lift “Sponsor an inch or more” prize draw winners announced

At the successful lifting of General Steam Navigations Boiler from the frames on Friday 2nd October, the prize draw as part of our  “Sponsor an inch or more” appeal also took place and the winners are detailed below.

Graham Muspratt makes the draw as the boiler is lifted using part or 35011 as the draw pot

The “Sponsor an inch or more” fund raising appeal was launched back in March this year and  very quickly raised the funds to cover the cost of the crane hire for the boiler lift.
The society would like to express our thanks to all whom to  took part and contributed to this major milestone in the restoration of General Steam Navigation back to her original 1950s condition.

The draw for prizes was made at significant points during the boiler lift and winners are:

  • Crane set up and ready to lift – GSN Pint Glass – Shaun Bradbury
  • First Inch lifted – GSN Mug – Ian Comley
  • Maximum lift point of the boiler reached – A years free Society Membership – Alex Clements
  • Boiler lifted clear of frames – A Graham Farish N gauge Merchant Navy Pacific model – Michael Hampton
  • Last inch of lift completed – GSN Mug – Andrew Charmer-Stevens
  • Boiler in new resting place – A Bachmann 00 gauge H2 Class locomotive – Alex Clements
  • Crane released from boiler – GSN Pint Glass – Simon Shutt
  • Boiler lift success – Bottle of Veuve Clicquot Champagne – Andrew Stokes

All the winners will be contacted by email on the next few days to make arrangements to send the prizes.

The major boiler lift milestone allows the project to more onto the next  exciting stages of restoration and details of how you can get involved with future fund raising campaigns and be a part of the success of the project will be announced soon.

As always any support would be gratefully appreciated. You can sign up for membership for only £12 per year here, donate to the Society here or even better join us as a shareholder here.


35011 General Steam Navigation boiler lifted for the first time in 61 years – a major milestone reached in the restoration project.

On 2nd October 2020, the boiler of Ex-SR Bulleid Merchant Navy Class, 35011 “General Steam Navigation” was successfully lifted from its frames for the first time since 1959.

The boiler was built by North British in Glasgow in January 1941 and has been attached for a total of 61 years since its last overhaul in July 1959.

The lift of the boiler followed a successful fund raising “sponsor and inch or more” campaign and prize draw to cover the cost of the suitable crane hire to lift the boiler.  A fully tubed boiler weighs 24 tonnes,  however the tubes, despite the restrictions due to Cocid-19,  were removed by volunteers of the society reducing the weight to around 20 tonnes.

“It’s a very exciting time for everyone involved in the 35011 General Steam Navigation restoration project,” said Andy Collett Chairman of the CIC. “The removal of the boiler is a big turning point as it allows us to commence the restoration of the chassis, which will be a big project in itself, taking several years to complete.”

Vice Chairman of the Swindon & Cricklade Railway, Allan Bott welcomed the positive news. “It’s great to see 35011 take the next big step in its restoration journey. It brings a much-needed boost following our forced closure due to COVID-19. With the line re-opening to passenger services on Sunday 4th October, our customers can now come and see 35011’s progress following the successful boiler lift.”

Work on 35011 will now be directed to the restoration of the chassis and further fund-raising campaigns will be launched in due course.


March Update 2020 – Boiler Lift Appeal

 Boiler lift “Sponsor an inch or more” and prize draw.

As with all things in life what goes up must come down… and the boiler is no different. It will need to be lifted clear of the chassis, swung away, and then lowered to its new temporary location.

The approximate cost of the crane hire will be £1500 that also equates to approximately the distance in actual up and down travel of 150 inches of the boiler by the time it has been raised to clear the chassis and lowered again.

We are therefore offering supporters the opportunity to sponsor a part of the lift for as little as £10 per inch, of course supporters can also sponsor multiple inches!

How to “Sponsor an inch or more”

To “Sponsor an inch or more” head to our campaign ‘JustGiving’ page here  to complete your sponsorship.

Free prize draw

Every “inch or more” sponsored will be entered into a free draw to win a number of prizes, be drawn at random at pivotal points during the boiler lift, including: model railway locomotives in N and 00 gauges including a star prize of a Graham Farish N Gauge Merchant Navy Pacific locomotive, a year’s free membership of the GSNLR Society, General Stream Navigation merchandise and other prizes.

The more inches sponsored increases your winning chances.

Note: the prize draw is registered with Plymouth City Council in accordance with the Gambling Act 2005 for non-commercial Society’s

Click here to sponsor an inch

AGM Cancelled

We also regret to inform you that we have had to cancel our Society and C.I.C. AGM’s planned for Saturday March 28th. The Swindon and Cricklade Railway have cancelled their Steam Gala and all trains until at least the end of April as a precaution against Covid-19 and your Board has decided that we should follow their very sensible lead.

We hope to be able to arrange the AGM’s for a later date when the current situation resolves itself and we shall announce a new date in a future edition of The Packet and will be writing to all shareholders as well. We apologise for any inconvenience caused to any of you who intended to attend the AGM’s but I am sure you will understand our decision under the circumstances.


Our volunteers have also been hard at work removing various components off the locomotive including the rear and middle brake hangers on the right hand side, the remaining parts of the slide bars from both sides, the outside exhaust steam pipes, the reversing screw and the regulator operating bar from inside the boiler. All of the removed components are then assessed, put into storage and if they are a component that is exclusive to the rebuilds they are offered to other Bullied owners group.

Trailing Truck

 Work was not just focused on removing components but also saw our volunteers test fit some of the components the Society had made last year. The main highlight was the trail fitting of all the components for the trailing truck. The spring beams were successfully installed with the hangers. The Society needs to acquire some new springs but was able to use the bogie springs for the test fiting. The axle box cover and dust cover were fitted which gave us the slight of a fully equipped fabricated trailing truck for the first time since the 1960s when GSN had the covers removed at Barry. The Society would once again like to thank all the members who sponsored the various components for the trailing truck.


The main focus on the work on the locomotive has been centred around detubing the boiler ready for the boiler lift. As it stands all of the bigger boiler tubes have been removed from the boiler and our volunteers have a start removing the small tubes.

The boiler lift will be part of a big on-site move so getting the boiler prepared and the funds in place beforehand will be key. Once again if you like to help fund the boiler you can “Sponsor an inch or more”  by donating to our campaign ‘JustGiving’ page here  to complete your sponsorship.

As always thank you for your continued support.

General Steam Navigation setting course for the Swindon and Cricklade Railway

35011 sets course for the Swindon and Cricklade Railway

The General Steam Navigation Locomotive Restoration Society are pleased to announce that they have agreed terms to move locomotive 35011 to the Swindon and Cricklade Railway in Wiltshire.

The Society restoring Merchant Navy class locomotive 35011 General Steam Navigation are working to retro convert the locomotive to its 1950s specification before the class were rebuilt into the more conventional form by British Railways. This includes restoring the iconic air smoothed casing along with Bulleid’s oil bath encased valve gear incorporating chain drive. Once complete, General Steam Navigation will be the first engine to be restored to as-built condition within the ranks of preserved Merchant Navy class locomotives.

By relocating the group and the locomotive to a publicly accessible site near Swindon, restoration will be able to step up a gear, with a target to complete the rolling chassis within the next five years. The Swindon and Cricklade’s Blunsdon station will become the new home for 35011.

The General Steam Navigation Locomotive Restoration Society was formed towards the end of 2015 with the aim of restoring 35011. The Society has made great advances since then, but volunteers were keen to find a permanent restoration  base for the locomotive.

“We are delighted that we can finally announce that the locomotive will be moving to The Swindon and Cricklade Railway in the near future” said Simon Shutt, Chairman of the General Steam Navigation Locomotive Restoration Society. “This move will enable us to take the project to the next step and escalate our efforts to put the steam back into General Steam Navigation.”

Working in association with other locomotive groups based at The Swindon and Cricklade Railway, the plan is to remove the locomotive boiler for the first time since it was withdrawn by British Railways, to allow thorough restoration of the locomotive frames and wheel sets.

“We are pleased to welcome this group to The Swindon and Cricklade Railway” said Mick Lay, chairman of the railway. “By relocating General Steam Navigation to the Swindon and Cricklade Railway both parties will benefit.” said Mick. “General Steam Navigation will be a valuable and useful locomotive when we extend to Cricklade and also help raise the profile of our railway while 35011 is restored. In giving General Steam Navigation a permanent home, we hope it will provide mutual support to our volunteers and the team working on her.”

The cost of the move has been priced up just under £9,000 which is where we need your help. We are fundraising to help cover as much as the cost as possible with the target being set at £4,000, the more money the Society can raise the more money that can be spent on components and help restore this mighty beast. If you can donate please consider supporting  the Society by visiting our Just Giving page below thank you.