Museum of Steam Power and Land Drainage
Steam Articles
Articles appearing here are written by members of various participating organisations, including Westonzoyland, Steam Scenes, West of England Steam Engine Society, East Anglian Traction Engine Society, Torbay Steam Fair. The articles may be freely published only by the participating organisations.
As I may have mentioned once or twice, when occasionally I feel the need to earn a living, I help out with Rule's Steam Gallopers, usually driving one of the lorries and building up/pulling down. (Incidentally the Foden is worthy of a Road Test in its own right, pity it's not steam...)
Anyway, one evening Michael Rule phoned me to say that he was opening for three weeks in London, but that he couldn't spend the whole three weeks stuck down there, so would I be able to go down and drive the centre engine while he was doing other things. He said, "I thought you would know a bit about steam engines, and if it all went wrong you could look at it and figure it out and not panic." Hmm. Anyway, I had recently been laid off by the bogroll firm so I said I would do it.
The Gallopers were built by the famous manufacturers, Savage of Kings Lynn, for travelling show-woman Maggie Collins in about 1893. They then went to the Collins family-owned seaside park at Seaburn, Sunderland until the late 1970s, after which they was put into store. They were purchased in semi-derelict condition by EATES member Derek Rule, who with his son Michael, rebuilt the ride and restored it to steam power. This work was carried out between 1984 and 1992.
The centre engine was built by Robert Tidman & Sons of Norwich possibly for Studts of Cardiff for use in a set of gallopers now at Butlins, Bognor Regis. The engine attended many early EATEC events in the ownership of Vice President Smudge Smith and his father.
Tidman's were based in Rosary Road, Norwich. Robert Tidman founded the business in 1847. Much of his early work covered the installation of small boilers and general millwrighting. After a few years Tidman's premises comprised blacksmith, boiler maker's and engineer's shops, constituting what had now become known as Bishop Bridge Iron Works. One lasting testament to their work is Norwich's Foundry Bridge, which was erected by them.
Probably Robert Tidman & Sons became best know for their fairground machinery, and for many years a machine of some sort was always in progress at Bishop Bridge Works. Of course as well as building the machines, they built the engines to power them. City of Cardiff (interestingly, Tidman's did not number their engines) was built in 1918 and is one of only ten Tidman centre engines now listed in the Traction Engine Register.
Prior to the London job starting, we were out at Tring and Warwick, which gave me an opportunity to watch the ins and outs of driving this thing - it all looked very easy, although my first attempt at shutting the regulator resulted in the ride going backwards, apparently a result of too many heavy people on one particular stroke...
Of course the first thing with any steam engine is steam, and that requires a fire... So I had to learn how to light up. Prior to doing this, it is necessary to ash out, as on any engine, and every 3-4 days the tubes should be swept. Due to the small size of this engine it is easiest to clean the firebox out by removing 3 firebars through the firehole door, and shuffling the others across. As well as ensuring a clean grate it also rotates the firebars. The ash is then raked from the ashpan, put a bucket and tipped into a convenient builder's skip...
Unlike the engines we are all used to, there is no forced draught on a centre engine, because the smoke has to go sideways before it can go up. In order to make it go up the chimney rather than back out of the firehole door it is necessary to light a second fire in the bottom of the centre pole, while the main fire gets going. There is a door for the purpose in the bottom of the pole, which when not in use is securely sealed with a gasket of old newspaper...
It's quite worrying, using diesel and rag to set fire to something very old, very lovely and largely wooden. But I had good advice, such as "Don't get ash under the ashpan, it will get hot and set fire to the truck..." Reassuring indeed...
The fire is started using newspaper (a copy of The Sun is about the right amount), sticks and a sprinkling of Homefire Ovals (which burn really well in this engine, mine hates them!)
Fire is one thing, but you will not get very far without water. In this case it is stored in plastic 50 gallon drums under the back of the centre truck, sucked up through a rubber pipe. The engine is fitted with a Buffalo lifting injector, which works "usually" and a pump, which works "sometimes".
Some of the aspects of the engine looked familiar to me, gauge glass, pressure gauge, and lubricators are all pretty much as standard. However there is no reversing lever, and the regulator opens through an arc, rather than the wheel favoured by Savage. The duplex layout makes for very clear lines which are pleasing to the eye, and the Tidman engines are particularly well proportioned.
The engine is very simple and straightforward, oiling points are obvious and accessible. A large mechanical lubricator is fitted, along with a displacement to each cylinder. Drive for the ride is taken from the end of the crankshaft via a nylon gear, which I would guess is neither Savage nor Tidman original but is more than up to the job.
Working pressure is 100psi, in practice the engine is run around the 75psi mark. After getting the fire going on Homefire we switched to Andy Polish Special. The main problem with this is some of the lumps are huge and do not fit into the Tidman's tiny firebox, but it is nearly as good as the Homefire and a lot cheaper! I could tell when steam was rising as "the leak" started - as a result of a dodgy gasket which has now been replaced, steam was coming out under the casting which holds the regulator etc.
My first effort at driving drew me to the conclusion that whatever I did to the regulator had little or no effect on the speed of the ride, but eventually I started to get a feel for it. Once the (hopefully many) riders are in place, a blast on the siren and the regulator is cracked open. Being duplex, in theory there shouldn't be a dead centre situation where the engine won't start. In practice occasionally it won't start (though it only did it to me once) and you have to ease the flywheel round a little. So, supposing all goes to plan, the ride starts nice and gently, and gradually increases speed until the horses start to swing out on their sliders, when the regulator is eased back to maintain a speed that is about right, with the horses around halfway out. That of course is the theory, in practice the speed varied from ride to ride. As a general rule, when the kiddies start going white and crying it is going too fast...
On one occasion while coaling up, I stood up and felt something brush the back of my head, when I realised everything spinning around me was a blur, I realised I had knocked the regulator open with my head, and shut it down quickly. Luckily the passengers at the time were enjoying the speed!
I was surprised how much one ride takes out of the engine, in terms of pulling steam and water down. This problem is much reduced once the engine is properly hot, after about an hour or so, the pressure is kept high and the injector used little and often. I had not used a lifting injector before but found it very easy, despite the lack of packing in the tap taking the skin off my hand by the end of the stint.
My firing problems were not helped by the firebars, which are best described (in a family magazine) as "tired" - fifteen years old and banana shaped. Michael advocated taking one out, as one was cracked anyway, and this I duly did. Not long into the following day I noticed that one of the others had fallen in half and was sitting in the ashpan. A big lump of coal kept in the resultant gap enabled me to complete that day's running, and when I raked through at the end of the day the one next to it had collapsed as well! Ferreting about in the Foden found three BRAND NEW spares! The following morning I fitted all of them, and the original cracked one I had removed before, and things were much improved - and I still had a spare, even if it was nearly in half as well!
The following day saw much more success, with a full set of bars, only a slight hangover, and a steady stream of punters. I soon realised that the engine is at its best once it is hot enough to singe the hair on my legs, which is also a great help on a cold December day. The rubber pipe only needs transferring to another drum once in the day, when all other frantic attempts to get the injector to lift have failed. The drums were filled from a convenient tap on the London job, but at other times we have to open a hydrant and run long lengths of cheapo garden hose to fill them up.
I found driving the centre engine completely different to engines I have driven before but was amazed at how quickly it responded to coaling-up or the injector - you can literally watch the needle and the water level change - but if you don't pay it proper attention it can soon catch you out. I'm not entirely proud of the fact I made the safety valve lift for only the second time since the boiler inspection, but there you go. I must thank Michael for the enjoyable experience, and I must also make special mention of Tom and Mike (Panda) for their assistance (and the drinks!) -and if you're ever hungry in Southwark, we recommend Hot Munchies, more for the comedy value than the catering...
