Bluebell Railway Atlantic Group
As work on the boiler continues, fabrication of its clothing is the main preoccupation of this report from Fred Bailey.
As no doubt you have seen in previous updates, we are reasonably comfortable with the machining of components, and the fabrication of heavy lumps of metal, but when it comes to the thinner sheet metal required for the details related to the boiler clothing sheets, then we are into a specialist area.
I have spent quite some time trying to find a company to make such items as the decorative mud hole door surrounds, the mouldings that fit to the boiler clothing but cover in the front corners of the firebox, plus that which encircles the backhead. Also we need a proper outer dome cover and some other parts that will not be seen (very unfortunately), these being the pockets that are inside the boiler clothing where the latter is cut away to clear the tops of the driving wheel splashers. Also we needed that company to have the capacity and capability to do this work at a sensible price. This work is far from being mass produced body panels and involves a mix of pressing onto simple tooling followed by skilled handwork for final forming and finishing.
The company now doing this work for us were very keen to put this through their apprentice school as it provided an ideal opportunity to learn the hand crafts on components with a function and use, not just an exercise. Just this last week two of the apprentices involved in this work together with their Training School Manager and Welding Supervisor visited us in Atlantic House and delivered the first components. To say I was impressed is an understatement!
The company to whom I refer is The Premier Group in Coventry. A number of the photographs that follow were taken by Mr. S. Burdett of that company and I will acknowledge his photographs accordingly. Note to other locomotive projects: please do not inundate them with work until ours is finished!
I am going to start with a few pictures showing part of the manufacturing process.
Right: The first stage is to make male and female plastic tooling and then form the dished portion with a rubber press. (S. Burdett, The Premier Group)
Below: After this the dish is clamped to the tool on an angle plate for the marking out of the shaped holes that pierce the component to allow the bridge on the mudhole door on the boiler to protrude. These doors have to be able to be removed without taking this surround off of the clothing sheet. From this point all of the work is down to manual dexterity. (S. Burdett, The Premier Group)
Next are the two finished articles, one seen from the inside, the other the outside. (Fred B.)
Below is one of the pockets to take the splashers, after pressing using the male and female tooling, but now mounted on the male tool and robustly clamped down with a solid backing piece to prevent distortion ready for the corner radius to be hand chased.
Next we have that corner being hand chased by one of the apprentices. (Both: S. Burdett, The Premier Group)
Now, looking into the pocket itself on the finished article. We will be drilling the fixing holes in this part once we have the clothing sheets properly located. But that is some way off as yet!
They are very difficult to photograph, but as these pockets fit to the boiler clothing, the whole item is curved, the pocket as well as the flange around it, to let it match both the boiler itself as well as the clothing sheet, although not touching the boiler itself. (Both: Fred B.)
Here we have the start of one of the firebox mouldings, being formed on the English wheel. This is a real black art and I think something that can only be learned by practice, practice, practice. By pushing and pulling the sheet metal between the two rollers, one above and one below the sheet and with some pressure between them the metal is slowly stretched on one side more than the other so making it deform into a curved shape. The art then comes in knowing in which direction one rolls the sheet to increase or decrease the curvature in the direction required. The whole shape is then matched to sheet metal templates. I may well detail this more in a later update. (Right and below: S. Burdett, The Premier Group)
The second photo below shows our visitors from The Premier Group. Left to right: John Watkins, the Training School Manager (also seen on the English Wheel), Lewis Prewett, Sheet Metal Apprentice, Gary Horton, Welding Supervisor, and Toby Casey, Sheet Metal Apprentice. (Fred B.)
Moving on to my more normal topics, the boiler is now fully riveted and we have done some preliminary low pressure air tests to look for obvious leakage.
We designed and had built a mini hydraulic squeeze riveter specifically to put in the rivets around the fire-hole door. There is insufficient room to manouvre a pneumatic rivet gun so this was our answer. Although I did some simple FEA on the 3D model of this item, with a 25 ton ram applying the squeeze onto a very hot rivet I wanted to make sure it was up to the job, so did some tests to check on the deflections especially at full load. Fortunately they were very similar to the results from the model.
Below is the riveter in position having just put in another rivet. Keith was adjusting the riveter's position inside the boiler and once all set I was heating the rivet, putting it in the hole for Keith to grab and hold with another pair of tongs whilst I got the underside snap in the riveter onto the rivet head. Once there he could dispose of his tongs and guide the upper snap onto the rivet. I meanwhile had my head next to the riveter frame and my foot on the valve operating the ram. All done as quick as possible. I hope you will forgive me for not getting an "action" photo! This also explains my deflection test!
Below we see all of the rivets in position. In addition to the heads one can see the plates were heavily countersunk on both sides (as made by the LNER).
Finally for this update, Keith looking for leaks with a flare - we have progressed from having our hats blown off, as you can see. Our old compressor has worked overtime at this, but about 10 psi or so can tell one a lot, and now we are using soapy water so that the bubbles show up the lesser leaks. The superheater flues are as yet only expanded and not belled or beaded. We will do this after the hydraulic test. No doubt on a full hydraulic we will find more leaks, but this method is a lot drier and certainly finds the worst of the problems early on.
We have also made up temporary low height "track" ready to wheel the tender chassis and the boiler outside, but due to our position in the yard and the other projects taking place around us we are likely to meet with some delay in moving the tender chassis and boiler. There are always jobs we can work on however and they all move the project forward.
Fred Bailey supplies an update, with photos illustrating the current state of this project.
First of all I must apologise yet again for the big gap in our updates, but the boiler work is not that photogenic and involves a lot of hard work (for us older folk) with a good deal of grunting and a pot or two of perspiration. However we have not all pushed off to pastures green but have been beavering away on the boiler, plus a few other bits and pieces.
The overall result is that we are getting quite close to its hydraulic test. That will take place out of doors later on in the year as we have no wish to flood our workshop, which has no pits or drainage. It does not matter how tight the boiler is, everything near will get wet. I hope this little update will be of interest to those of you following and hopefully supporting this project.
The photo on the right is of the throatplate, now finally riveted to the foundation ring, and with new stays fitted where required in the welded-in patch plate. Also in view are the rather awkward curved mud hole doors with their bridges. All new of course to fit the patch plates.
The first below shows the right hand side of the firebox. The studs that hold the blowdown valve still need to be fitted, and of course so will the valve itself. This is finished and in stock.
All the small tubes and the superheater flues have received 2 coats of a graphite-rich coating prior to fitting as mentioned in my last update, but it is quite a time consuming (and not to mention messy) job, but hopefully it will be worth it in due course. A quick calculation shows that we have covered roughly 1/10th of an acre with graphite paint!
The picture on the left was taken through one of the superheater flue holes, looking towards the firebox, and shows all of the small tubes in place with the exception of those that are in amongst the flue tubes. As the top of our tender chassis which sits in front of the boiler is higher than most of the small tube holes, each one had to be inserted higher up than needed, then threaded through a lower hole at the firebox end, prior to shuffling to and fro before arriving in its final place.
The flues weighing in the order of 1.5 cwt (76 kg) needed to be handled semi-mechanically, and below is the last one about to be put in to the boiler - a red letter day for us, but only the start of another process - expanding! One might be able to make out a tool filling up one of the tube holes and this is an expanding toothed collet that grips the inside of the tube and allows one to turn the tube to screw it into the thread in the copper at the firebox end.
On the right, a volunteer member of the "Old mans' gang" that makes up our build team getting value for money out of his membership of the gymnasium that is The Bluebell Railway - about £20 per year for Senior Citizens at the 5 year rate. Just think what proper gym membership must cost - all that exercise to get aching muscles for no result! Here we have another flue expanded, so a few aches, but with a positive worthwhile result!
I will not go through the rest of the tubing in detail, but suffice to say, below is the front tubeplate with all the flues and tubes expanded. Unfortunately further very skilled processes need to be applied to the tube ends, especially in the firebox, but these will be carried out after a pressure test. If done beforehand and a leak is found on test it makes a further expansion of the offending tube almost impossible.
The next view below shows the backhead with most of the blanking plates and the regulator rod and its gland installed ready for testing. Unfortunately we are still waiting for the special frame for our new small hydraulic riveter to be made by one of our local sub-contractors. As usual, you find a company that produces good work, who then become known and busier and then their deliveries start to slip. The space available around the door ring (which needs riveting) is rather too limited to use two pneumatic riveting guns, a squeezer is more compact, not to say quieter.
Concurrently with all the boiler work, one of our regular volunteers has completely stripped and rebuilt a four-feed Detroit sight-feed lubricator. This has needed a lot of new parts, some made by him, some purchased and others made by our volunteer turner. This is the advantage of having a small but good team who all work together. On this fact a lot depends. It is hard enough tackling these projects without having "people" problems. They are the most destructive of all. The main thing is although a serious project it must also be fun!
This is all one can see of the Westinghouse pump and its new governor, now the front footplating is in place and the pump covers installed!
Another job we could not put off any longer was drilling and tapping new holes for the front boiler support and for the centre grate support and also the drilling and burning out of old original studs that held the rear side expansion brackets and the ashpan. All of this work entailed working upside down under the boiler's foundation ring. (We do not have facilities in Atlantic House to turn boilers over). In the first photo below one can see the pilot holes that have been drilled with our small magnetic based drill.
These holes needed to be opened out to a size larger than the capacity of the smaller drill, so we used our air drill, as seen in the middle photo below. With limited room between the floor and the foundation ring some drills had to be considerably cut back and reground, but tools such as these have to be expendable up to a point - pun not intended! Even after all of this the remains of the studs needed further attention from the oxy-acetylene to get the last remnants out.
My last picture shows the safety valves bolted down on to the boiler. (They are shown with the gagging links fitted to allow for a hydraulic test to a pressure beyond its working steam pressure). These links are replaced with the final safety links after the hydraulic test. Also in view is one of the upper inspection doors with its cover / clamp plate. These door cover plates are about flush with the clothing sheets so are not too conspicuous. Only boilers for the C1's built after about 1936 had these doors. Prior to that and in common with the Brighton engines the boilers had plugs in these positions. The later doors are tricky to fit, but provide excellent access for inspecting the firebox crown and all of the crown stays etc.
Fred Bailey supplies another update, with photos showing recent progress on this project.
The component sponsorship list has also been updated.
On the right we have a view of the chassis with the smokebox door and its surround sitting on the smokebox saddle. Its true position is about a foot nearer the front of the engine, so that the Westinghouse pump will actually be under the smokebox. Hardly ideal for maintenance purposes but to fit it to the smokebox side would severely limit forward visibility and might also foul the loading gauge, and space between the frames is (and was) taken up with loads of other equipment. Hence the position selected by the LB&SCR for the pumps on the H classes of Atlantic.
As stated earlier the boiler has been our priority and the first row of rivets around the foundation ring have been removed and are now re-riveted by our two boiler smiths from the main workshop assisted by a couple of us from the Atlantic crew. Work on boilers is a job that is not only hard physically, but demands a great deal of thought, planning and (although not realised by the majority) precision. The folks that do this work day in and day out are the only reason you can see preserved steam ANYWHERE today! So be thankful there are such people prepared to do this work and we ought to go out of our way to ensure we keep their services.
The photograph below, although a little blurred (there is not time to pose for cameras), shows a rivet about to be put in its hole prior to being double gunned down. This means two hand held rivet guns being used, one on each end of the rivet. The remaining rivets in the upper row have now been removed although a good few were in no mood to come out without a fight, but never the less we are now ready to finish the foundation ring riveting once we can obtain the assistance of our (younger and fitter) boiler smiths once they can find a gap in their more important work in the main loco workshops which obviously must take priority.
The second photo below shows the 'J' pipe, on top of which sits the regulator, and the main steam pipe going out through the front tube-plate. We have conducted a pressure test on the joint between the 'J' pipe and the steam pipe and it seems to be satisfactory, so the studs to take the superheater header have now been installed, so filling up the holes that can be seen around the steam-pipe.
On the left is a picture of the start of the check calibration on one of the movements within the Westinghouse Duplex pressure gauge. This is being carried out on a dead-weight pressure gauge tester that works via a "sack" containing water that is pressurised by the oil used in the tester itself. This then ensures that the oil in the test machine does not come into contact with the gauge internals. The outer needle is not fitted whilst checking the inner one as shown.
A little while ago we produced some 3D CAD models of the various cast parts that go towards the making of a Westinghouse air pump governor. The patterns and castings were then made and machined. These together with all of the many other parts have now been produced by others with the result we now have in stock a brand new Westinghouse pump governor, seen in the first photo below. The machining and assembly, not to mention the "tinkering" required, have produced an excellent item that we are told works like a dream as it has been tested in service on an engine.
At long last we have now made a start with the painting and installing of the boiler tubes, as seen below. Each tube gets two coats of Apexior prior to installing it into the boiler. This is quite a slow job - the painting and drying of the tubes a few at a time taking a lot longer than their fitting. The superheater flues will be slower still as there are handling problems due to their weight to be considered. Putting them in their holes is the easy part as they all then have to be expanded and beaded. "Fun" to come!
Fred Bailey supplied this update in early May, so apologies for the time taken to get it online.
It has been some time since we have provided an update on the Atlantic, because the progress that is being made is generally not very showy, but does provide the basis for the next major stages. Obviously the boiler is our priority but various small items have added up to a further delay.
The replacement plates with new openings for mud hole doors are now fully welded into position, the welds have passed their stringent examination satisfactorily and new copper stays to replace those removed with the old plate are now in position and await final heading.
We are now ready to start riveting the foundation ring, but due to our team's more senior age profiles we are awaiting a time when one or two of the younger, fitter, skilled boiler team members from the main works can assist us. Unfortunately they are very busy working on boilers that are needed to provide the motive power to service the core business of the railway. We hope to get underway in June with this work.
The first photo shows a sight not seen for a long time. We have cleared all of our material stocks off of the top of the tender chassis and put the larger components on one side to allow us to start preparations for tubing the boiler. We intend using a special coating on these tubes to give them a good start in life within our boiler. There is quite a lot of work here as all 134 small tubes and 32 large tubes, all 16 feet long, need to be thoroughly de-greased and then given two coats of the preservative "paint". The first few tubes can be seen laying on the tender floor. We were initially intending to raise the boiler to tube it, but we have found that this will not now be necessary.
The photos below are an earlier view of the two steam pipes in the base of the smoke box saddle (round flanges) leading into the valve chests and in the centre the exhaust exit flange, and a later view showing the blanking plates to help protect the top of the valve chests from ash etc. and the upper blast-pipe now in position - although it will be removed when adding the boiler and smoke box to the chassis.
At the rear of the engine (as seen on the left) more pipes are getting installed along with another air reservoir that provides the air to power the reverser.
Also in the cab (right) we have been fitting the spectacle plate window frames and (not shown) the catches that keep them closed.
Below is the valve, mounted on the cab side above the reverser, that operates both the clutch to lock the weigh shaft and applies air to the reverser to assist in reversing the engine. No air assist is required to put the engine in forward gear.
The double Ramsbottom safety valves, below, are now virtually complete. These will be pressure tested shortly to prove the body integrity and then will be re-assembled and approximately set for the blowing off pressure. Once that is done, washers are made to go between the counter-bore in the body and the underside of the adjuster to ensure that no further adjustments can be made that would increase the set pressure.
For some time the chassis has looked complete, and in essence it was, however it is not complete until all the fixings are tightened and retained. This operation is best left to be done as one operation moving methodically from part to part. Steam locomotives try from the first moment they move to reduce themselves to their component parts by whatever means possible and this is where the very smallest of components become the most important.
It is difficult to show the amount of work involved in doing this work but this next picture below shows an easily accessible example outside the frames. This is the big end cotter and taper bolt with its nuts behind it. Note the cotter has pinch bolts in the side, plus a cotter fitted tight to the underside of the rod, which in turn is split pinned. The taper bolt has a nut and locknut again with a fitted cotter and split pin. This sort of thing can be found throughout the chassis especially between the frames where it can't be easily seen.
Work has started on fitting up the smokebox door and its surround. The hinges were rescued off of the smokebox that came attached to the boiler all those years ago. With some slight modifications they seem to fit very well to our new smokebox door. The hinges would be difficult and expensive to manufacture today, being forgings with twists and bends to make them fit the door.
A fund raising appeal for the money required to complete the project was launched in 2000, and a combination of gifts made via the Bluebell Railway Trust, and standing orders set up to provide a steady income to the project have provided funding for the present work. However, more is still needed to complete the project, and the best way in which you can help is by setting up a small, regular, standing order to the Bluebell Railway Trust under Gift Aid, since this enables the Trust to reclaim the basic rate tax you have paid, and (if you are a higher rate tax-payer) enables you to reclaim some tax as well.
Would you like to sponsor a specific part of the locomotive? The latest component list is available, from which you can choose a wide variety of important parts of the locomotive. You may prefer to use the combined Sponsorship and GiftAid form available as a pdf.
A combined Donation, GiftAid and Standing Order form is available as a pdf document.
For further details contact David Jones.