Sir Sagramore, 3.5” gauge Maunsell King Arthur

[Florence Locomotive Works]

Very very glad I was able to find out what happened to the engine I spent far to much time gawking at on the Station Road Steam website! Its probably the greatest piece of work I've seen come through there. Will you be steaming the engine "in anger" on a club track so to speak?

 

Douglas

[CF MRC]

Yes, Douglas, my engines are never shelf queens.  It will run at the North London SME, which has quite a challenging track.

 

Today was the day of the rivet / bolt for Sir Sagramore.  On the prototype, the top of the cab was designed to be removable for improved access during heavy shoppings.  Most of the bolts representing the fixings are round headed 10BA, permanently fixed and dummy, but some are slotted to allow dismantling the cab.

It will make lining out a bit more challenging but shouldn’t be too bad, considering the fairly large scale. 

Tim

Edited February 18, 2022 by CF MRC

[CF MRC]

I have re-united the cab with the rest of the loco, returning to the rather cooler big workshop to do so. It still fits!

 

Tim

[richard i]

Looks great but the boiler bands look a bit thick and melty 

richard 

[CF MRC]

Where would the world be without cable ties though…?

 

Tim

[CF MRC]

The original name, Sir Percivale, is no more, he’s changed to Sir Sagramore.  The only surviving engine of the class, Sir Lamiel, is undergoing a major restoration.
https://www.sirlamiel.org.uk/index.php/2022/02/10/777-sir-lamiel-progress-report/
I therefore thought it a very good cause to help a little, so I’ve joined the funding round table. This has meant that the engine has changed name, Sir Sagramore being an available name that I could use and an engine that was photographed many times when new.




The engine is looking quite racy with the full cab. In true Stalinesque form, I have airbrushed out the old name in the title …

Tim

Edited February 18, 2022 by CF MRC

[St Enodoc]

On 12/02/2022 at 05:47, CF MRC said:

It will run at the North London SME, which has quite a challenging track.

That's at Colney Heath, IIRC?

[CF MRC]

Yes it is indeed. The line is about 1km long, with some good gradients and curves. 
 

Tim

Edited February 19, 2022 by CF MRC

[St Enodoc]

2 hours ago, CF MRC said:

Yes it is indeed. The line is about 1km long, with some good gradients and curves. 
 

Tim

Thanks. I remember it from over 50 years ago, when my Dad took me to a couple of open days there.

[CF MRC]

3 hours ago, St Enodoc said:

Thanks. I remember it from over 50 years ago, when my Dad took me to a couple of open days there.

It celebrates it’s 60th anniversary this year. 
 

Tim

[CF MRC]

After a bit of a diversion to other bigger and smaller projects, I have returned to the NBL works. 
Sir Sagramore has a hydrostatic lubricator, which needed a 180 deg (in line) globe valve to isolate the steam feed when required. Commercial examples are rather crude. Ian Jaycroft had made the top half of a valve but I couldn’t find the globe itself in any of the bits bags. 

The bottom half was turned up in the lathe with a small hole for the valve seat and a larger tapped hole for the valve spindle body. 

This was set up in the drill, having filed two flats on the sides of the valve body. The angled holes were drilled by eye. 

The gods were being benevolent as both holes ended up in the correct place. 

Two pipes, threaded 3/32” 60ME, with a flared base were made. The openings to the valve chamber were also increased in size with a dental bur. These were then blocked off with Tippex and the assembly clamped together. 

Two large endodontic files were used to open out the feed and delivery channels, visible above and below one another. 

The sub assemblies can now be seen. After silver soldering the shape of the valve was established using burs, stones and abrasive rubbers.  

The delivery hole can be seen at the top of the pipe. 

There may be ‘proper’ ways of making globe valves, but this one passes the ‘puff’ test. 

Tim

 

[CF MRC]

It’s quite difficult to work out how someone else intended to make an incomplete model. The livesteam manifold on Sir Sagramore clearly needed two plugs at each end but it was only fairly thin copper pipe that they could fix into. Using silver solder at this late stage would have been much too risky for the assembly. 

Consensus at the NLSME was that if a high temp soft solder was to be used then a screw thread would be advisable to give auxiliary retention to hold the plug. 

The pipe just about took a 7/32” 40 TPI ME thread, but a plug made to that size was much too loose (A 1/4” 40 ME tap would have been much too big for the wall thickness). The solution was to make a 1/4” 40 ME plug with the die tightened up and wind it in with force using a large pin chuck.  This swaged the copper pipe, increasing its size for the plug which was then soft soldered in place with Comsol. 

The expanded pipe size is just discernible on the RHS

Bit naughty really, but there is no way those plugs are coming out any time soon.

Tim

[CF MRC]

The original injector steam feed pipes had an un-prototypical swan neck exit from the boiler valve. 

I therefore made a right angle fitting to neaten up the plumbing. 

Original valve at the top. The right angle extension was threaded 3/16” 60 TPI ME at each end. A 90 degree chunk of metal was removed with a diamond slitting disc. It was bent to shape with frequent annealing and then silver soldered. 

Still not strictly correct, but Ian’s original valves are a work of art which I wanted to keep.

Tim
 

[CF MRC]

The injectors on Sir Sagramore were originally partially made by Ian Jaycroft. Unfortunately, both were incomplete and a challenge to finish. 

On the RHS I have therefore fitted a ’Chiverton’ 16oz injector from Paul Pavier. The water feed pipe to the boiler clack had a right angle fitting made, a requirement of having limited space. The internal passage is polished to aid water flow.

The injector has fairly large fixings so it is placed low down (as per prototype) and has a simplified water supply.  The bottom water feed pipe again has a bespoke 90degree fitting to keep the plumbing neat.

The moth-eaten steam supply pipe at the top is just a placeholder: I’m awaiting some more 1/8” pipe to reinstate this. 

There will be a discrete accessible water control valve fitted in the tender giving a well streamlined water flow. 

Ian’s original set up with the incomplete miniature injector had plumbing that was a bit of a snakes wedding, with generally rather small bore pipes for the water feed. The handle for the water control valve was very small and quite inaccessible within the cab. I may, however, try Ian’s arrangement (duplicated) on the LHS, where access to the water valve is better, as the engine only needs one reliable working injector, there also being hand and axle driven pumps to get water in the boiler. Reverse engineering the injector could be very challenging, but probably worth a go. 
 

Tim

Edited October 18, 2022 by CF MRC

[CF MRC]

Attention has now turned to the steam supply to the oil reservoir of the sight feed lubricator.  This pipe was roughed out for shape with some thick electrical single core cable. 

The actual pipe was made in two halves with the little globe valve in the middle. The bending was done by hand with frequent annealing. 

I couldn’t resist putting in place some of the other fittings. The backhead will have a false cover, to which will be attached the firebox door, pressure gauge, and injector steam valves. The round head bolts on the regulator gland will be replaced. with something more appropriate. 
 

Tim

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Edited November 6, 2022 by CF MRC

[D-A-T]

I like the screw reverser. Very neatly done. 

[CF MRC]

3 hours ago, D-A-T said:

I like the screw reverser. Very neatly done. 

Beautifully made by Ian Jaycroft, the original builder. 

Tim

Edited November 6, 2022 by CF MRC

[CF MRC]

After a few hours work a 1” pipe now links up the blower valve with the boiler hollow stay. Not exactly greased lightening progress, but making all the fittings takes a bit of time.

 

 

I think the back head cleading will probably follow - that should be fun.
 

Tim

 

Edited November 6, 2022 by CF MRC

[CF MRC]

The back head cleading was initially sketched out using a paper template. 

This was then transferred to 0.6mm thick brass and cut out using a dental engine, a diamond disc and TC trimmers.

Ian Jaycroft made a superb quarter-round brass bezel.

The two components will be soldered together to make a more solid structure, so that there aren’t any gaps. The firebox door assembly (visible in the previous posts) will be bolted through the cleading.

 

Tim

 

 

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[CF MRC]

I have had a busy few days working on the back head for Sir Sagramore. I decided to use 16BA bolts to secure the quarter round-bezel to the cleading rather than soldering: much more controllable.  The firebox door assembly was also bolted on. The restraining bracket for the door arm will probably be beefed up a bit - I don’t think it will otherwise survive my poor aim when firing…

. 

The cleading was fixed to the back head with a couple of short 10BA bolts into some stays. This then allowed for the pressure gauge and LH injector steam valve spindle mounting to be attached using 14BA slotted screws (I might change these to hex bolts). 

The routing of all the pipes is a real snake’s wedding. 

Other than a few small jobs, it just needs the RH injector valve spindle support making and some restraining collars on the shafts to more or less complete the top end fittings. 

 

Tim

[CF MRC]

Sorry to be a bit of a broken record but the cab of Sir Sagramore has now got to a stage where the top end is virtually complete (and I need a break from plumbing). Just need to tighten up a few screws and move on to a larger scale interlude this weekend.

Replacing the front section of the cab improves the appearance considerably.

 

Tim

[CF MRC]

Back to big stuff for a while. The original water control for the RH injector on Sir Sagramore was fiddly and deep inside the cab and not at all practical. With the new injector’s streamlined plumbing I thought a water valve towards the back of the tender would be more practical. A commercial valve has therefore been adapted to fit the water pipe below the tender tank.  

The handle was made and located with a taper pin so that it can be removed for photos. Once it is chemically blacked I don’t think it will be too conspicuous. 

I think it should be reasonably convenient to operate.

Fortuitously, the taper pin rotates against a positive stop cut into the inside of the valence - which makes positioning it much easier for ‘off’.

The next job will be to re-make the tender brake wheel, which currently has four spokes and it should have six. 

 

Tim

 

 

 

 

[Kylestrome]

On 14/11/2022 at 12:37, CF MRC said:

The routing of all the pipes is a real snake’s wedding.

 

Tim, how do you make all the bends in the copper pipes without them going flat or kinking, or is that not a problem?

 

David

[CF MRC]

One can use pipe bending springs and other devices, but I generally just bend them by hand for the smallish diameter pipes on this engine. They are constantly being  re-annealed though. If you don’t do that they will distort. 
 

Tim

[CF MRC]

For the tender brake wheel on Sir Sagramore a steel disc was turned up and drilled on a rotary table. A styrene spoke template can also be seen resting in the wheel face. 

This plastic template was used to mark out the spokes using the obligatory gramophone needle. 

The material between the spokes was fretted out within 40 minutes.

After cleaning up with files

The final finishing, e.g. rounding the spokes used steel burs, stones and a rotary steel brush. 

Here it is In-situ. Awaiting a knob and a steel 10BA nut. Ian Jaycroft’s gear drive to the brakes is beautifully engineered, with two quite large bevel gears. It could be made smaller with a gear set from a contra-angle dental hand-piece: but there are other more pressing things to be getting on with…

Herewith the spinning knob for the handle. 

 

Tim

Edited March 31, 2023 by CF MRC
Add handle