What Gradient ?

"John Turner" wrote

are some fairly stiff

No kidding. A friend of mine who is a serious trans-Europe basher, has showed me his slides of the recent TGV works under construction, and the swoopiness is indeed terrific. In the old days they'd sooner do curves than gradients; nowadays with speed the priority and electric power on tap they'd sooner do gradients than curves. Come to that, a GNER electric probably goes faster up Stoke Bank faster than Mallard came down it, and certainly beats a Deltic in either direction.

A pity model motors don't behave like their prototype equivalents. Much of model behaviour is attributable to the poor torque transmission across worm gears: if someone were to invent a motor the size and shape of a pound coin that does what an Escap 1219 does only at a fifth of the rotational speed so it could be attached solely to spur gears, and ideally withstand brief high stall current, we'd not worry about half the things we do. Except that moany British manufacturers would still find price-based excuses not to use it...

Tony Clarke

Reply to
Tony Clarke
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It was a French company which introduced a RTR Class 40 to the British market so all the other stuff is forgiven.

(kim)

Reply to
kim

Don't forget the baby's foot and the ears of barley, as still used today in UK shoe sizes!

Cheers, Steve

Reply to
Steve W

See my web on the subject.

Terry Flynn

formatting link
HO wagon weight and locomotive tractive effort estimates

DC control circuit diagrams

HO scale track and wheel standards

Any scale track standard and wheel spread sheet

Reply to
NSWGR

The thing about the TGV system is that it's used exclusively by high-speed passenger trains with few intermediate stops. No local stopping trains or freight trains to impede them, and no level crossings. It's about 10 years since I took the Eurostar from London to Paris. After a leisurely ~100km/h jaunt through Kent on the 3rd-rail system, the pans were raised and the speed increased to 200km/h through the Chunnel. Soon after emerging into the French countryside, an announcement was made that the speed of 300km/h had been reached. The line runs parallel to a motorway, on which the vehicles look like static toys. A train going in the opposite direction at a relative 600km/h takes only a couple of seconds to pass.

Reply to
MartinS

"MartinS" wrote

Yes indeed Martin I've travelled on it often, and is regarded as incredibly steep, and is very near to my 2% gradient criteria. Didn't it create chaos when they tried to haul trains up it using the SR Schools class 4-4-0 'Repton' some years ago?

John.

Reply to
John Turner

Steep and curving, which might be more of a problem. That said, Stirling 1 didn't seem to have any problems with it 15-odd years back (can't recall the load exactly, though IIRC it was three or four coaches).

Reply to
Andrew Robert Breen

Hornby Q1 hauls just as well which surprised me but the BoB less. Heljan

47 not as powerful as the Hornby 50 but plenty and a double motored Hornby 47 without traction tyres as good as the Heljan.

Chris

Chris

Reply to
Chris

I was there a few years ago at Goathland station when 'Repton', coming up the gradient, was forced to a stop by a failed home signal. After the problem was corrected, there was a grand exhibition of smoke and steam, but she did manage to get the train moving and into the station.

Reply to
MartinS

It might be worth building an incline and experimenting which is what I did. I tried an increase in height of 2.5 inches over 6 feet with locos pulling 5 coaches. The majority of Bachmann locos were rubbish but the Hornby locos were better. I reduced the incline so the length was nearer 8 feet and the performance was better with Hornby and Bachmann locos. Some locos still couldn't manage 5 coaches but as I couldn't design in a gentler gradient I accepted that some locos would just have to haul reduced length trains on the route with the incline. Just like real life really.

Kevin

Reply to
Kevin

If you're running DCC, then do as in real life, stick a banker on the back. This could make for interesting working, returning the bank engine back down to the bottom of the grade. Regards, Bill.

Reply to
William Pearce

The prospect of banking is the only advantage that I can see. With conventional analogue control I find it possible to control 5 (max) locos but with so many locos available to me I think that the identification of locos would defeat me. I do bank trains -- as has been said, the Bk 5's are just as hopeless as in real life and an OXO can help no end.

Reply to
Peter Abraham

I've added a pilot to reduce the risk of derailment on my helix.

Chris

Reply to
Chris

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