Brighton Atlantic: 32424 Beachy Head

Not that anyone has the first idea what an 'ume' is!

 

The answer is the same as it was 9 months ago last time you asked (page 36 of the thread) - only one boiler was ever at Sheffield Park.

http://www.bluebell-railway.co.uk/bluebell/locos/atlantic/background.html

Tom

 

That I do agree with Miff.

 

Regarding adhesion, as ever, it's more complicated than that.
In theory, a loco should be more sure footed if more of its wheels are driving wheels, and more of the weight is on those wheels.
In reality, lots of other factors complicate the picture so much that individual designs and locos often don't perform as would be expected based on those simple rules.
Likewise wheel size should make a difference, and does to calculated tractive effort. But lots of loco types defy their apparent theoretical performance, in both directions!
On Atlantics I'd recommend "Atlantic - the well beloved engine" by R.A.S.Henessey which covers the type in a very entertaining way. He mentions, for example, that a certain LB&SC driver (Alf Aylwin) took pride in starting heavy London trains out of Brighton with no 421 almost silently and with no wheelslip at all.
Don't forget, Atlantics took heavy trains over the L&Y route (I've a photo in front of me of one with at least 10 and a van on heading west from Yorkshire, and that was with 7'3" drivers!) or over the Waverley route, or on the Nord mainline (up and down), and across hilly southern Germany - not to mention up Eskdale (do the scaling conversions: it's an impressive feat!)
This one will do fine on the Bluebell, once the drivers learn how to handle her. The right handling of an engine is everything: a cack-handed driver can spin a 0-8-0T, and a soft-handed one can climb mountains with a 4-2-2.

 

I know Stroudley carried out a lot of work on different grades of tyre materials and profiles around the time the "Gladstone" class was being developed.

How stable was the steel formula and section used for (just bullhead) rails over the years? I'd imagine adhesion differed depending on those variables.

 

As I have too.............

 

That's always the case. Unless the painter gets it wrong, of course.

 

I am very much looking forward to seeing Beachy Head finished and have checked their webpages periodically for years to see how they are getting on with it. They have just quietly got on with it and the quality of the construction seems excellent. It will also be an interesting loco to see operating and the only Atlantic apart from potentially the Didcot Saint too. I also like the choice of a Pre grouping design as they are rarer in operating condition.

A couple of quick questions

1 Did these Engines ever operate on the Bluebell line in LBSCR/Southern/BR days ? I have only seen one photo of the original Beachy Head there on a railtour but was that just a one off. ?
2 Who actually owns it, is it the Bluebell railway themselves or an external group ?
3 How have they raised the funds to pay for it ?

 

1) Yes.

2) It is owned by the Bluebell Railway

3) A mixture of one off and regular donations; component sponsorship; sales of donated material, especially books and models

Tom

 

There is a reference to them working over the line on this page - just below the photo of the original Beachy Head - http://www.semgonline.com/steam/h1-h2_02.html

Steve B

 

My maths isn't good enough to do the sums, but when I look at the tractive effort, the weight and CoG of the locomotives, and the height of the drawbar I find it hard to believe the oft repeated tales about weight transfer. There just doesn't seem to be enough force and leverage for the effect to be more than marginal. Happy to be corrected by someone who can do the maths though.
I have seen at least one GWR source claim that the principle difference is in regulator design, and the crew just has more control of how they put down the power.

 

Whilst we are already well off topic who in their right mind uses the regulator on a superheated locomotive to finely control the power output to restrict slipping? With the volume of steam already in the elements once the regulator is opened the reverser is where any good driver would fine tune the power output - perhaps the GWR did not have any



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Isn't it Newton's Third Law?

 

Agreed but the is one exception, at low speed when starting a train from rest in difficult conditions (heavy train, gradient, curves, wet rail, etc) if the loco starts to slip in those circumstances you must close the regulator or their could be dire consequences. Many drivers will pump the regulator to great effect. Also if a loco starts to slip at speed the only way stop it is to close the regulator.

 

Something on the lines of applying a force and there is an opposite opposing one.......?

 

For confirmation of every aspect of Gary's statement, watch just about any clip - or if you have the time .... every clip - of a Ffesterbahn loco wrestling an up service back into motion while departing Tan-y-Bwlch and consider how much JGF the driver of a Double Fairlie is experiencing at that point.

Oddly enough, the ruling gradients of both Bluebell and Ffesterbahn aren't a million miles apart ..... though any similarity pretty much ends right there!

When it comes to 'Beachy Head', given the originals hefted heavy services from rest up to Grosvenor Bridge each and every time they departed Victoria Station for over forty years, I'm at something of a loss as to why anyone is querying either the strength or adhesive characteristics of the design.

 

So assuming that wheel is actually fixed to the track, the force applied to rotate the wheel in one direction acts to rotate the locomotive in the opposite. Theory works perfectly well with a single driving axle, but surely any cumulative effect that brings more force to be the rear of the locomotive/ rear drivers would apply a lifting force on the forward drivers - .Although on a 4-6-0 the C of G is slightly forward of the centre drivers. ?

 

I think slipping has more to do with the skill of the driver as a general rule , but design also plays a part .the Princess Royals were much more prone to slip than a Duchess .
I have seen a Hall slipping and sliding like a novice skater while leaving Paddington - but generally 4-6-0 s don't suffer too badly .
I have seen an A2 take nearly 4 minutes to get the last coach into Gasworks tunnel ,and other 4-6-2 s get under way in perfect order on the same track ,on the same day , but the LNER pacifics could usually be relied on to do some skating . most would drop sand on the rail at the X as they backed down to the train.
superheat has nowt to do with it , as an engine that has stood waiting for the board to come off will not have a hot fire.
how easy the regulator is to manage must have a bearing on starting ability .when the reg.is 1st opened the cylinders will get the full boiler pressure until the wheels have made a few revs which is why most? engines will perform an initial slip before the cylinder pressure drops and comes under the control of the regulator.
faulty weight distribution is a factor , probably not such an issue in preservation where time is taken to get it right.
weight transference also plays a part .this will cause more weight to be placed on the rear driver when accelerating . a pony truck under the cab will reduce this . you get the same thing happening in FWvsRW drive cars.
other stuff also plays a part , such as wheel profile (possibly a bigger factor than it is given credit for , and rail conditions , plus maximum effort outputs at almost any speed
the drivers skill is in assessing what he has to deal with at any given time . some do this better than others.
the Brighton Atlantic probably will have some "moments" and I imagine the weather forecast will have a bearing on the engine of choice on any given day

 

Yes, every action has an equal and opposite reaction, demonstrated in exaggerated form by a motorbike wheelie.

 

Opening the throttle too quickly on a monocycle demonstrates this rather well too ...... and the resultant "hamstering" is much funnier to watch!

Image courtesy www.techeblog.com: