In Search of the lost Nutty

'Nutty' is one of a peculiar breed of specialised locomotives that Sentinel made in the 1920s for brickworks use. Their prime requirement was to be very squat in height; very, very squat (5'2" in fact)!

Nutty lookalike - Works number 7243 built in 1928
(Photo from Sentinel Drivers' Club collection)

Built as works number 7701 in 1929 to a 2' 11" gauge, Nutty was one of about five constructed using steam waggon components.

In order to reduce the height as much as possible, the engine was mounted horizontally and the boiler very near to the ground. It also made driving a remarkably intimate experience!

No room for foot-plate passengers!
(Photo from SDC collection)

Neither of the above photos are actually Nutty; however, the next one certainly is.

Nutty in August 1971 at the Welshpool & Llanfair Light Railway
(Photo SDC collection)

The inner workings are clearly visible if you click to enlarge the picture.

I became aware of Nutty through conversations with curators of the Narrow Gauge Railway Museum in Tywyn, Gwynedd, at the terminus of the Talyllyn Railway (where I can be found volunteering on occasions). Nutty is actually owned by the NGRM but it never seems to be found anywhere near the museum!

Although originally built to a gauge of 2'11", it was re-gauged to 2'6" some years ago and it ran on the Welshpool and Llanfair Light Railway for a while. Since that time, I do not know exactly where it has been but I'm led to believe it has spent time at Railworld in Peterborough. In 2012, it made its way to the Leyton Buzzard Railway where it is on display at the Stonehenge Works station.

I visited the LBR on Wednesday 16th July 2014 and was made very welcome indeed. I wanted to poke my digital camera into Nutty's various nooks and crannies to assess its general state. I now have around 170 photos, not all are included here!

Nutty under cover at Stonehenge Works

Yes, it is chain-driven!

Side-on view

Cab internals showing the boiler

'Under the bonnet' view showing the engine beneath the water tank

Engine, water tank and boiler feed pump

Bijou accommodation for the driver!

There are clearly a number of components missing and regrettably I omitted to enquire if they existed. However, it was a good day out and many queries answered as to the construction of this strange locomotive.

Now who volunteers to restore Nutty, reduce the gauge by another 3" and run it on the Talyllyn railway?

April 2024: I've been asked for an assembly drawing of Nutty for modelling purposes. Regrettably this request came about a year ago so please accept my apologies for not monitoring blog comments.

I hope this drawing will help:

See my Reference Material page for information sources.

Sentinel Conversion Loco (and no clothes!) (4)

Mike Hart has sent some more photos about his progress restoring Gervase at Elsecar Heritage Railway.

Mike comments (28th Feb. 2013): "Today we shunted Gervase out of the shed at Great Central Railway so it could go on the pit to be weighed and have its springs adjusted. We will leave Gervase with her clothes off for ease of access and any final adjustments when we steam her up for test running. Nearly there - at last!"

These photos were taken outside Locomotive Maintenance Services at The Great Central Railway, Loughborough. Earlier photos (2), Earlier photos (1).

Front view showing vacuum brake and steam heating fittings

Off-side front

Near side showing mechanical lubricator mechanism
Compare with earlier view

Single Chain drive and gear-case
This is very different to 7109's dual chains and twin gear-cases

Off-side rear

Now how about a signal red under-belly for 7109?

Sentinel Conversion Loco takes shape (3)

Mike Hart has been keeping me informed about his progress restoring Gervase at Elsecar Heritage Railway.

In my first article, Gervase was reported as steaming for the first time in 50 years and that Locomotive Maintenance Services at The Great Central Railway, Loughborough, would be completing the restoration work.

These photos were taken by Mike during activities at Loughborough on 7th February 2013.

New Side-rodding in place

Rear Cab View

New Axle Boxes to take the white-metalled brass bearings

White-metalling in progress

6-Feed mechanical lubricator for axle-box crowns

Near-side view with cover removed

There are some dates already pencilled-in for Gervase's first few steaming appearances this year. I'll help to spread the word when the pencil has turned to ink!

Keep up the good work Mike.

Sentinel Conversion Loco Steams Again (2)

After posting the article on Gervase's restoration progress, I found a couple of photos of Gervase of old in Tony Thomas's photo collection.

Gervase at Tenterden 21st October 1969
Photo Courtesy of Tony Thomas

Gervase at Standard Brick Co., Redhill 13th January 1951
Photo Courtesy of Tony Thomas

Sentinel Conversion Loco Steams Again (1)

Mike Hart from Elsecar Heritage Railway, recently announced that his current restoration project, a Sentinel Conversion Loco named Gervase, had steamed again on June 30th 2012 for the first time in 50 years.

Gervase (1) photo courtesy Mike Hart

As well as preparing the boiler for its final certification exam, the engine unit was run, the vacuum and steam brake equipment was tested and the steam heating and all the other bits and bobs checked out. At the end of the day, a pleasingly small snagging list was left to sort out.

Gervase (2) photo courtesy Mike Hart

At the end of July the loco was planned to be moved to the railway workshops at The Great Central Railway, Loughborough, where Locomotive Maintenance Services would make and fit new axle boxes and horn guides, recondition the side rods and perform various other jobs to finally finish the loco’s restoration.

Gervase (3) photo courtesy Mike Hart

Mike’s aim is to have the loco operating at Elsecar by Christmas 2012 and ready for a trip to the Kent & East Sussex Railway Gala in May 2013 to celebrate the 50th anniversary of its first steaming at Tenterden.

Gervase (4) photo courtesy Mike Hart

Sentinel works no. 6807, Gervase, is the only known remaining potentially serviceable Sentinel ‘conversion’ loco. It was originally a Manning Wardle but adapted by Sentinel in 1928 to use a vertical boiler and vertical twin cylinder engine of steam road waggon design.

Although the cab and engine housings bear a resemblance to the Fry's type of 100 HP Sentinel, there the similarity ends - it has side rods instead of chains linking the front and rear axles.

This is a really interesting project and I am looking forward to visiting Elsecar to see it in action.

Click here for a couple of historic photos.

200HP Pre-War Sentinel Locos (2)

The 1920s were not well known for mass production and, of its type, Sentinel 7109 was the first of not very many, only 14 in total. 7109 was actually a basic design around which variants and enhancements could be made to suit particular customer's requirements.

Two 200HP design variants were made to suit the Somerset & Dorset at Radstock where a low bridge required reduced maximum height. These were the Radstock Sentinels with their lowered cab roofs.

However, another pair of 200HP specials, with works' numbers 8147, 8148, was delivered in 1929 to the LNER. Eventually designated as Y10s, they were specifically intended for use on the Wisbech and Upwell Tramway.

On these, a second, front-mounted cab was added to make them capable of being driven from the front in either direction. Tramway standards of the time dictated that 'skirts' and 'cow-catchers' should also be fitted for public protection.

Twin Cab Design with Cow-catchers

Knowing 7109 inside out, I've always found these twin cab variants fascinating. In particular, being aware of what it's like under 7109's engine covers, it would not be a nice place to work! There are hot pipes and non-elbow-friendly protrusions all over the place! These locos were withdrawn from the W&U Tramway after only a short service and one can only speculate the reason. However, subsequently, they were transferred to Yarmouth docks where they gave many years' good service.

I have recently been sent a 1933 instruction manual covering the various LNER Sentinel Locos and Railcars. It includes a diagram of the layout of this Y10 double-cabbed loco. (Click the diagram to enlarge it).

General layout of both front and rear cabs

It shows how the front cab regulator lever was connected across the top of the central water tank to the regulator valve itself in the rear cab. Obviously, this loco could not be single-man operated whilst driving from the front as a fireman was still needed by the boiler at the rear.

Various identities have been suggested for Sentinel 7109 when it gets into service; however, a variant with a front mounted cab is one I had not considered until now!

100 HP Sentinel Locos (Fry's Type)

I've been asked for information about the Fry's Sentinel loco which was rescued and returned to its original home area in 2010. Avon Valley Railway are doing the restoration work.

As a late addendum to '100HP Pre-war Sentinel Locos' posted in 2011, the following pictures are taken from the 1931 Sentinel catalogue '"Sentinel" Patent Locomotives'. It includes the following details of the Fry's loco type (Click the pictures to enlarge):

The Fry's Loco

100HP Loco as used at Fry's in Keynsham

See page 53!

Old catalogues do come in handy sometimes!

The Power of the Double-Engined Sentinels

What can you do with a Sentinel locomotive rated at 200 HP?

John Hutchings, of the Industrial Locomotive Society, kindly sent me a copy of a very interesting letter recently (September 2011).

Recall that Sentinel 7109 was the first of a series of eight pre-war double engined Sentinel locos with the unusual curvaceous profile. Being a first-off, its performance needed to be marketed to potential customers and so it was delivered to the LMS at Newton Heath, Manchester for evaluation.

The letter below describes the tests and shows how impressed the observers were with 7109 at the start of 1928. (Click the picture to enlarge it for reading).

Sentinel 7109 performance
(Letter courtesy of John Hutchings, Industrial Locomotive Society).
(Note: this was retyped by JH as the original is in poor condition).

So these are the results of the actual tests done on 7109 which inspired the S&DJR Co Ltd to purchase their two similar locos for use at Radstock.

Clearly, you can do quite a lot with a 200 HP loco so long as you don't want to do it too quickly!

200HP Pre-war Sentinel Locos (1)

Sentinel 7109 is a 200 HP type; however, Sentinel also produced various other 200 HP types before they settled on the 7109 configuration. One such type proposed was the double centre-engined type shown below. However (see comments below the posting), this type was never apparently built although others were (but I don't have diagrams for them!).

Double Centre-engined 200 HP Locomotive

The front engine was intended to be linked to the front axle and the rear engine to the rear. Those specified to be low geared (and hence high torque) also had their engines locked together to prevent wheel-spin on one axle.

Compare this to Sentinel 7109 with its engines at the front (and check the comments below).

Sentinel 7109 - A balanced double-engined 200 HP locomotive

Both the types and others could be built with double gearing; however, 7109 is only single geared.

100HP Pre-war Sentinel Locos

I found a wonderful book recently named "Sentinel" Patent Locomotives that covers much more than just Sentinel 7109. Although it was reprinted in 1974, my copy was the genuine article published by the Sentinel Waggon Works in 1931 as a kind of technical marketing catalogue for pre-war locomotives.

For example, here's a LNER Y3 type in drawing format.

Y3

And the Y1 type; however, the difference is not apparent except to those who looked underneath. 

Y1

The Y3 had a gearbox below its engine to enable two levels of capability whereas the Y1 drove directly from the engine's crankshaft. The Y3 was thus the more flexible locomotive.

Sadly, no Y3s have survived.