INSIDE MOTION News and Views from the

TYNESIDE SOCIETY of MODEL and EXPERIMENTAL ENGINEERS

No. 12 February 2021

Preamble

I‟m not sure if it‟s too late now to wish you all a Happy New Year, or a bit premature given that CV-19 still has a firm grip on all our lives. That we will come out of it eventually is certain, but at what further cost to our lives and liberties remains to be seen. In the interim, we all soldier on as best we can.

The Naming of the Club Platform and Signal Box

In the last copy of Inside Motion we asked for Platform/Signal Box names as a fitting memory to our late Chairman Jim Stephenson - something with a suitable railway theme. The only name that came up was “STEPHENSON HALT” which was suggested by both our editor Mike and Stu Davidson.

With the passage of time it was thought that new members would not know the history behind the name so Stu suggested we put together a Blue Plaque explaining all ….

The plaque will be screwed to a wall inside the signal box. A large name sign will be made and attached to the signal box front. Peter Newby

People

I was inundated by two responses to “spot the nonsense” in the December issue. Honourable mention goes to Jim Scott who was first in, and Michael Dibb, the only other member who played. Both expressed scepticism that Stephenson‟s canary was called Trevor. As it is not recorded that GS even had a canary, we‟ll never know for sure.

Junior Engineer Sam Yeeles has had another photograph selected and published in Heritage Railway magazine‟s January issue.

RSH 0-4-0ST No.7098 “Sir Cecil A Cochrane” powers away from a snowy East Tanfield with the Christmas Eve “North Pole Express” in December 2020

Member’s Musings

Lining Boiler Bands Dave Nesbitt

When coming to the lining on 46205 I have used different methods, i.e. transfers on the tender and cylinder covers and a lining pen on the rest of the engine. When it came to the boiler bands I was inclined to use transfers but reluctant as the scale boiler bands on a Princess Royal are noticeably more narrow than the 5" gauge bands commercially available. If I used scale boiler bands then the transfers would overlap the band, with the only option to slit the transfer down the middle and overlap in the centre ! Not something I fancied, so I decided to try the lining pen. Rubbish results followed trying to get the fine orange lines onto the edges of the band, so it was scratchy head time.

Luckily the diameters of the three bands were very close to the diameter of the Myford faceplate with the idea of mounting the lining pen onto a magnetic stand on the cross slide and then line the bands fastened to the faceplate. The lining pen handle was drilled out and a bush fitted to allow the pen to pivot on the rod mounted on the magnetic stand. This worked ok but even the small clearance on the pivot meant the pen could move sideways enough to spoil the line - hence the very important lacky band fixed to the magnetic stand and pen which eliminated this error. See photo.

Even on the slowest back-geared speed the spindle rpm was much too fast, so I made up an adapter to go into the battery drill and onto the end of the lathe motor drive. This attempt was carried out with the wife Cath on the drill and me watching the pen. It was sort of successful but the drill speed control was unstable and not easy for her or me in the time it took to complete one revolution of the band. In the end, pushing or pulling the countershaft to drive the spindle whilst looking at the pen was a very smooth and controllable way of lining the bands, with the added bonus of the ability to space the lines accurately using the cross slide engaged onto the lead-screw. I used a Peter Spoerer lining pen with a 0.025" stylus for the orange and a 0.050" for the thicker black centreline (two passes).

Happy Lining !

Trial by Injector

Michael Mee Steam trains have always held a fascination for me since I was very young. When we used to live close to the main line from the Channel ports to London, Mr Bullied‟s Merchant Navy Class often put in an appearance, awe inspiring ! Then there was the day Dad took me to see a friend who had a 5” garden railway, no less, and a whole day spent driving a Speedy ! The seed was sown. Decades later at sea, a fellow engineer produced a set of drawings for a Martin Evans tank loco which he was building and the penny dropped - I could build one of these. After all, had I not been trained to fix ships when they broke down (which they did from time to time, sometimes quite spectacularly) ? My own Speedy took shape, all made at home including the boiler, except the injectors, which later proved to be a little problematic at times. Still, it did have the axle pump, but that had its problems as well. It was quite powerful and would quickly fill the boiler and have to be re-circulated, it also depressed the steam pressure somewhat. It was fed from both tanks but only re-circulated to the left tank, so that overflowed, as the other tank went dry, not ideal and what happens when stopped? Use one of the injectors if they would condescend to work, or the hand pump. No - that‟s too much like hard work. I did years ago come across a little gem of one of the tricks that was tried, fullsize, before injectors were invented, the engine was run up against the buffers and the regulator left open to keep the wheels turning and thus the axle pump going!!! The wear on the wheels and track must have been terrible, still I suppose it did stop the boiler running dry and exploding in the station! But back to the injectors. It is well known that steam engines have a soul and a mind of their own, some days at the track will be wonderful, all will go well and on others it will take a right huff and nothing will go right, and in my experience it‟s usually the injectors in a bad mood. So what goes wrong ? Simple as an injector may seem, it really is quite a sophisticated device. For instance, take the steam cone - it‟s about 1/2” long, the inlet taper of 13deg narrows down to the orifice at about .040” dia and then opens up again at 9deg. So it is a surprise to find out that on leaving the cone the steam is travelling at well over the speed of sound and I‟ve seen that in two different sources ! Around the cone exit is feed water which is picked up by the steam and hurtles in to the combining cone where the mixture condenses into a mass of warm water travelling somewhat slower, from there it enters the discharge cone where speed is traded into pressure and then into the pipe-work leading to the boiler check valve. The warm water is still travelling at some speed, sufficient to lift the check valve and enter the boiler. There is quite a delicate heat balance going on here, too much steam or too little water and condensation is not complete, the flow is disrupted and hot steamy water comes out of the overflow. Too much water, the flow rate is low, not enough to enter the boiler and you get a jet of water from the overflow. It is also vital that all these nozzles and cones are perfectly in line, anything not flowing straight will disrupt the flow, concentricity is important. Scale has a similar effect, so it is useful to pickle the individual pieces in dilute citric acid annually, particularly the steam cone. Manufacturing errors can upset everything, its important that all the internal parts are perfectly made and correctly spaced from each other or it may function badly if at all. The worst I have seen is where the cones were not machined, just a drilled hole through the various parts.

Speedy‟s injectors were a cantankerous lot, sometimes O.K. sometimes not, a very moody bunch! The problem was eventually solved when I heard about Chiverton Type Injectors, they are made by Len Steel in small batches and sold by PavierSteam, there was a 16oz vertical one left, fitted it to Speedy and instant success, you could even put the steam on first. It also coped well with the warm feed water that tank locos suffer from. Try www.paviersteam.com/fittings-accessories/chiverton-injectors/ By this time I had a copy D.A.G.Brown‟s book Miniature Injectors, inside and out which is a mine of information and suggests that if you can make the parts perfect to the nearest thou it will work and he gives drawing for several sizes. The Merchant Navy, Brockell Bank Line, by this time already had a pair of Chiverton type vertical injectors, but was in need of a brake vacuum ejector and there was one in DAG Browns book. The Bullied locos have a few funnies about them one of which is steam brakes on the loco and vacuum on the tender, it was worth a try so an afternoon in the workshop and much to my surprise I had a perfectly working ejector, it is now on the loco. On this engine, vacuum puts the tender brakes on, I know this is the wrong way round, but it means that one simple steam valve works everything and the whole loco stops without needing the hand brake on the driving truck. Buoyed by success with the vacuum ejector was it possible to make an injector? Worth a try, nearly everything is covered in the book. The first thing is to make a jig to hold all the body parts together while soldering them together, no problems there. Now come the taper reamers and this is a bit of a testy job, you will need 13deg and 9deg tapers and the 9deg needs to be accurate, but setting the topslide over to 4.5deg needs a bit of cunning to get it accurate, this is detailed in the book, then there is halving the tapered bit and hardening it is a test of skills. One thing I did not find in the book was how to set the depth collar on the taper reamer. Eventually the penny dropped, taking the 18oz injector, the steam cone requires an orifice of .041” dia at .180” in from the cone outlet, the answer is to machine a brass button of .180” thick and once a pilot hole is through, use the taper reamer to enlarge it until a .041” gauge will just go through ( the chuck end of miniature drills is handy here ) then lock the depth collar in place. It‟s worth noting here that the injectors are dimensioned for 80psi boilers, if using on 100psi the .041” orifice is probably better reduced to about .038” --- .039” It restricts the steam quantity a bit to suit the rest of the injector. The rest of the parts just need thou perfect machining and accurate positioning within the body. One other point found was that when machining the cones the first cut to produce a flat end to drill the pilot in will need a needle file brushed over it to get rid of the microscopic pip which will throw the drill off sideways, normal pilot drills are too big here but might be used to make an accurately centred dent which the drill can centre in. It was found that if accurately centred the pilot hole drill would not wander even down to 1/2” depth. ( new quality drill used here ) Not bad for a 30 thou drill. I made two of these injectors reckoning that the first would probably be a disaster, but no, both worked perfectly, nearly as good as the Chiverton Types. So it is possible to make your own injectors, just follow the instructions and be thou-perfect with the dimensions. I can see no reason why those of us in the club with machining experience could not make injectors, they are not difficult but do need care and precision. Go on give it a try, it‟s not really a black art.

The Old Man’s Link

Martin Ashley

I seem to remember from reading the various tales of the old railwaymen that Top Link drivers whose legs (or eyesight) had gone were put out to grass in the “Old Man‟s Link”. A bit like the days when we had “remedial streams” in schools that were taught “by PE Teachers whose legs had gone” (I quote from an in-service training day I attended during the non-PC early 1990s, with all relevant disclaimers).

Moving from the Top Link to the Old Man‟s Link basically meant moving from commanding a Royal Scot out of Euston (ok - A2 out of the „Cross for Green Engine people) to a Jinty pottering in the goods sidings at Crewe.

Covid has prompted me to join the Old Man‟s Link ! It‟s an idea that‟s been fermenting for some time. A 94-mile round trip to the Club has always been a disincentive, and loading a large main-line engine (until recently a B1) back into a workshop that you can‟t reverse a car up to at the end of it is even more of a disincentive for regular running. So, for this year, I added a spur to an engine shed on my short garden line. It‟s now just a matter of unlocking the doors of Shed 52D and wheeling her out. It works beautifully with my 0-4-4 Ajax/Achilles, but that has a pole reverser. Problem with the B1 is that it can almost take longer to wind from full forwards to full reverse than it takes to run the length of the line !

Then the penny dropped. Being a GL5 member, I thought “why not do what GL5 do – shunt trucks !” I can‟t extend my line across the village green (much as the occasional admiring bystander would like me to) but I can extend the network of sidings. So, the B1 has been duly traded in for a proverbial Jinty and I‟m now on my third wagon project whilst marking out the trackbed for a start in March when, hopefully, the weather is dry enough. I‟ll write another article on the pitfalls for a beginner builder of 5” gauge wagons when I have enough convincing photos of No. 3, an LNWR cattle wagon. All I can say at this stage is that I wish I‟d acquired a copy of Doug Hewson‟s amazing HMRS book Constructing 5” Gauge Wagons before I‟d started nos. 1 and 2. Meanwhile the picture is of wagon number 2 doing duty on the Christmas Eve beer train.

Of course, I hope to bring the Jinty to the club just as soon as it‟s allowed as it‟ll be interesting to see what she‟ll do on the main line !

. Quite Interesting

Jim Scott Poplars have flowers carried on catkins, and pollen from male flowers on one tree is transferred on the wind to female flowers on another tree. Female and male catkins look very similar but male catkins soon drop off after releasing pollen, whereas female catkins turn green when fertilised and then later release white seeds which litter the ground like cotton. The four Grey Poplars near the station comprise both male and female trees, but I can't tell you which is which. We also have several White Poplars at the far west of the site, suckers from these can be found coming up a considerable distance from the parent trees. Also, as part of the Brewery landscaping, a fairly rare (to these parts) Black Poplar was planted in the north boundary hedge.

This photo was taken on 30th June 2020. Not snow of course but a carpet of airborne seed from the female Poplar tree.

Postamble

Thanks as ever to those contributors who have made this issue possible. I was fortunate to have a

couple of items “in hand” from December – otherwise this would have been a rather thin affair.

I really would rather have too much material than too little, so to your New Year Resolutions add

“Send Mike Something”.

Meanwhile, keep well and keep busy.

Contact information

Newsletter Editor – Mike Maguire – mike.maguire@btinternet.com

Club Secretary – Linda Nicholls – lindanic@sky.com – 01 670 816072

Website – www.tsmee.co.uk Webmaster – John Rowley – webmaster@tsmee.co.uk

Headquarters and Multi-gauge Track – Exhibition Park, Newcastle upon Tyne NE2 4PZ