Seems like you got some good advice already so I’ll just say
Welcome Shelley!
Don’t forget that passenger cars ranged from around 70 feet in length to around 90 feet in length in standard gauge.
The true limiting factor of how many cars you can pull will be the design of you layout. Will a long train look ridiculous, with the locomotive chasing the caboose, about three feet behind? Or, if you are fortunate enough to have a larger layout, will your PA and two freight cars and a caboose get lost? How long are the passing sidings?
In any case, welcome aboard, Shelly. This is the place where you get your answers questioned. Bart has the coffee brewing and there is a place for you by the fire. Pull up a chair. The 10:27 is late again, so we have time for a story or two.
small or weak powerpacks have just 1 Amp. so that bridgewerk you are considering will not be the limiting factor.
Usually, the number of cars I have. Occasionally, the distance around the short loop back to the crossing.
Shelley so far you have ben give all the advice I could think of. I have the USA PA/PB set up and love it. I have had 20 cars behind them and could go more, but then again I have a 0 grade loop I run on with 16 and 20 foot die curves.
hope this helped and welcome
I stripped the plastic gears in an LGB Mogul (the ubiquitous #6 Colorado Southern) trying to pull more than 13 USA reefers around a 180’ mainline with a 1.5% grade. I have easily pulled 20 reefers with a USAT SD70-MAC on a friend’s flat layout with big curves. The limiting factor on my layout is the length of the passing sidings (each about 15’). Oh, yes, I have weighted down my reefers with little bags of sand (cheaper than lead) so they hold the track, but then that makes a heavier consist for any given loco to pull. A friend has pulled 48 cars on a flat layout with two lashed up USAT GP40s.
In order to answer this question, which depends on many factors, you should start by telling us everything you can.
Your maximum grade, and the length of the grade would help. That’s one of the biggest factors.
USAT PA’s don’t draw any significantly greater current than anything else. I have 5 of them. I have an ammeter on my layout. There’s some unusual characteristics of some USAT locos, which seems to have evolved into the saying that all USAT locos draw a lot more current.
Another factor is if you are still running the traction tires on your PA’s.
on the flat, with reasonable curves, you should be able to pull 40 cars. Up a grade that decreases sharply.
Regards, Greg
In most cases the length of a train is governed by the longest passing siding. However, if you do not have any passing sidings, then you are only governed by how many engines and cars fit on the track.
Ric Golding said:Or what looks good to you. Not having large, expansive curves, any more than 6 cars on my RR looks goofy to me. Ralph
In most cases the length of a train is governed by the longest passing siding. However, if you do not have any passing sidings, then you are only governed by how many engines and cars fit on the track.
Ralph Berg said:WOW Ralph has rooster on his railroad..... :)Ric Golding said:Or what looks good to you. Not having large, expansive curves, any more than 6 cars on my RR looks goofy to me. Ralph
In most cases the length of a train is governed by the longest passing siding. However, if you do not have any passing sidings, then you are only governed by how many engines and cars fit on the track.
Ric Golding said:
In most cases the length of a train is governed by the longest passing siding. However, if you do not have any passing sidings, then you are only governed by how many engines and cars fit on the track.
The tails of my wye are my limiting factor; or of I plan on ‘doubling’ the wye, then the grade leading to the front yard is my next limit. No one has mentioned couplers. Especially if you have grades, couplers can be a limiting factor. Even on the flat, each brand has a limit of how much weight it can draw before failing. This wreck was a result of too much weight on a Bachmann coupler going up a steep grade…
(http://photo.cvsry.com/Derail1-640.jpg)
(http://photo.cvsry.com/Derail2-640.jpg)
(Apologies to the regulars for showing this for the hundredth time 
Jon Radder said:Oops, time to call the "hand of God" big hook!
This wreck was a result of too much weight on a Bachmann coupler going up a steep grade...
Uh-oh, appears kingpin might have broken off the box car.
Forrest Scott Wood said:
Oops, time to call the “hand of God” big hook! Uh-oh, appears kingpin might have broken off the box car.
Yes, and Yes…
Good couplers should be a given if you are going for long trains. I pull 45-50 cars up a 3.4% grade with no couplers pulling apart.
So, I think in trying to answer the original question, it’s still grades, minimum curvature, and locomotive pulling power.
Regards, Greg
Us 1:20.3 NG’ers don’t have to worry too much about train length.
I typically run 5 -7 cars.
The only exception is a 24 car ore load.
Then I need a helper engine.
I’ll let the modern day guys run their 100 car freights.
The only reason I commented, is because the OP stated:
“how many cars can my ALCO PA-B engine pull realistically?”
So, he is modern day, 1:29, not narrow gauge, and he did ask how many cars, implying something more than just a few.
Regards, Greg
We are about to see if we can break all the rules we set for the garden railway build so that we can run a point-to-point section of line.
- nothing less than r3 track
- no grades
- no tunnels
- no overpasses
- no grade level rail crossings
I suspect most of the climb will involve r2 track but we may need to slip in a bit of r1. I’m wondering what the maximum grade a LGB Mogul can do with 3-10 cars and whether the long orient express cars could make this treacherous route.
Thoughts?
Railroad train lengths for me depend on the railroad that you are running on, that is do you have long mainline trackage, or short winding trackage layout. Most outdoor railroads are the short winding type, thus long trains really just don’t fit well and look out of place on these layouts. For me I’ve always been a narrow gauge person, thus short trains are what I run on my layout and others, but if I was a mainline runner I would defiantly want to run my trains on large layout where I could pull as many cars to give those SD-70’s that look of what it was built for. If you have a RL Hobbies style track at your disposal then running long trains might be your thing, but it not very satisfying as a layout I would want in my backyard. Main thing is I would want my trains to run as trouble free as possible and dealing with derailment, couple problems, track power, etc. are things I would try to stay from. I have very few problems with 5-6 car trains and being a narrow gauge person it works well for me. Once again, G Scale is in most cases is not a “rivet counter” hobby, so if it works for you, go for it.
1 Like
Do your best to stay away from the R1 unless you only plan to run LGB equipment. LGB specifically designed their engines to run on R1, but they don’t always look good doing so. Your tightest curve will be the limiting factor on loco and car length due to end swing. avoid S-Curves, especially on small radius. My Fn3 passenger cars will not traverse back-to-back 10Ft radius (R3?) switches forming an S due to coupling. I can hand push them through that S and even into an R1 siding for storage. It’s the couplers that pull the trucks off the track in tight curves.
One of my first layouts was a Christmas tree circle later expanded to include a “yard”. My only loco at the time was a USA Trains GP9 and the circle was all R1. By using hook and loop couplers to accommodate the swing, I was able to run short trains on the R1 circle.
Grade will be your limiting factor for train length. Ball bearing upgrades can help this. My Outdoor has a steep curving grade that approaches 5% ins spots. My C-19 will only pull two Fn3 passenger cars up that grade, on a good day. Some days if the rail is a little slick, a helper is needed.
Great to see your layout taking shape. Isn’t winter closing in on you now?