My 4 x 8, (HO scale), has not yet been divided into Cab Control because I'm still not quite sure whether it would be practical for such a small layout. And as of now, I only have ONE power connection to the track. at the far end for testing purposes only. And it's more than adequate, tho' I might add another when I'm reay to start running trains.
I put an inexpensive, big, bulky Lifelike GP on the track and right BEHIND IT, I put an Atlas RS-1. 'n they're off! The Lifelike was soon behind the Atlas, having caught up with it after two laps and just about ready to start pushing it from behind.
Can someone explain? The Atlas was 3 times the price of the Lifelike!
High speed does not equal quality. An engine that runs smoothly and reliably at slower speeds is very desirable in model railroading, for switching operations and for more prototypical mainline running. The slower running speed of the Atlas is a feature they promote.
The big difference is in the gearing and probably the motor.
As someone else also noted, the Atlas unit is designed for slow speed operation. To do that Atlas gears the unit such that its "high speed" (i.e. at full 12v DC) is relatively low. In doing that, you then have much better control of the speed via your power pack control within the range of operation.
No explanation, but my old math teacher would have had a field day. Train A leaves the station at 4 PM traveling 50 inches per minute, and Train B leaves at 4:10 PM going 15 inches per minute faster. At what time will train B meet train A? Arrrgh!!!
Railway modellers tend to judge their models on their ability to run at scale speeds and pulling power rather than for their ability to run races. Proper gearing requires more sophisticated engineering which tends to cost more.
I would suggest DCC rather than cab control on a 4x8 layout because with the restricted block lengths and cab control you will end up throwing switches more frequently than will be considered to be fun.
Different locos, even "identical" ones from the same manufacturer may run at different speeds. There are just lots of variables in addition to voltage, internal engine friction, wheel friction, gearing, etc. With DCC you can use speed tables and other settings (start voltage, midpoint, etc.) to minimize the different engine speeds at the same throttle setting.
Ed
in article snipped-for-privacy@ihug.co.nz, Greg.P. at snipped-for-privacy@ihug.co.nz wrote on 3/10/05 11:53 AM:
Oh, my, can the apocalypse be far away? Greg recommended DCC ;-)
I did use cab control on a 4x8 when I returned to the hobby in 1996 (stock atlas plan with inside and outside loops, and a couple of siding areas). It wound up being 5 control areas (each loop, upper siding, and two for an internal "yard"). With three power packs, I could run two trains continuously, plus one other in one of the siding or yard areas. It worked fine, so DC cab control can be used easily enough on a smallish layout without excessive switch throwing.
I did convert the layout to DCC from common rail DC and it was a matter of wiring all the control areas together (or just throwing all the switches to connect them to a single "power pack", in this case the booster), connecting the booster, installing decoders and running. Took a single afternoon. For me (maybe not for others), running the DCC version was so much easier. I could take an engine out of the yard, get on the main line and drive it up to the siding with no switch throwing. Of course, I did have to pay attention to where the other trains were running and deal with their speeds and stop them as appropriate to avoid collisions: my first dealing with what signaling and road rules were all about.
So even with DCC, you shouldn't just drive trains about: you need to either mimic the prototype you are modeling, or at least understand basic operation rules and such so that you don't have chaos.
"M> > My 4 x 8, (HO scale), has not yet been divided into Cab Control because "M> > I'm still not quite sure whether it would be practical for such a small "M> > layout. And as of now, I only have ONE power connection to the track. "M> > at the far end for testing purposes only. And it's more than adequate, "M> > tho' I might add another when I'm reay to start running trains. "M> >
"M> > I put an inexpensive, big, bulky Lifelike GP on the track and right "M> > BEHIND IT, I put an Atlas RS-1. 'n they're off! The Lifelike was soon "M> > behind the Atlas, having caught up with it after two laps and just "M> > about ready to start pushing it from behind. "M> >
"M> > Can someone explain? The Atlas was 3 times the price of the Lifelike! "M> >
"M> > Thanks, "M> > Mike "M> >
"M> "M> High speed does not equal quality. An engine that runs smoothly and "M> reliably at slower speeds is very desirable in model railroading, for "M> switching operations and for more prototypical mainline running. The "M> slower running speed of the Atlas is a feature they promote.
Also: The lower gear ratio means more pulling power. How many (properly weighted) cars can you put behind the Lifelike GP before it 'stalls'? How many behind the Atlas?
The slower speed of the Atlas means you can spot cars accurately and not 'crash' couple cars.
"M> -- Bill McC. "M> "M>
\/ Robert Heller ||InterNet: snipped-for-privacy@cs.umass.edu
There is no standard speed for a loco to run at a particular voltage. Different makers use different mechanisms and different motors and this means that they will indeed run at different speeds. If you're going to be running with more locos then the cars require, it may be wise to invest in some dummy locos so that you don't have any buvcking problems between different locos. If you do plan on running more than one maker on a train, you need to make sure that there is enough load back there in the train so that the fast loco tends to run with the slower loco. This can be a problem with heavy grades as you may have too much powr for the levle part of the layout but not enough for the hill. The only solution to this is to only buy locos that tend to run together in the first place. Weighting locos will tend to help the problem as the fast loco will lug down a lot more before slipping and causing problems. Also, runnign the fast loco first will make the bucking a lot less. FWIW, I once swapped the dirve out of a brass loco for a friend so that he'd have the same type drive in all of his locos so that they would all tend to run together without problems. Steam is a lot more sensitive to the different speed problem.
-- Why isn't there an Ozone Hole at the NORTH Pole?
It's actually easier (and cheaper) to make a model locomotive that runs fast rather than one that runs slow. Little kids want to see how fast their train will go, adults who've stuck with model trains tend to want to se how slow it'll go!
Now who in their right mind would ride a train going only 50 inches per minute???? Yeah I hated those math problems too!! I remember blurting out in HS math, "Who the hell only drives at 45 MPH?" math teacher was not amused.....
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