Reverse Loop

[majordadsage]

I have decided to go around the room with a 30" deep bench. The total length will be approximately 26'.

I want to run the trains....I like the long "straight-a-ways" but, will have several rural settings on the layout.

I have never seriously considered a "reverse loop" but, feel that it may have some real advantages with my layout. The bench will L shaped with 2 36"x36" Turn-a-rounds at each end. One wall is a little over 15' and the other wall is a little less than 10'.

It sure seems to me that have an auto reverse loop at each end would sure make a lot of sense.....one less track necessary for the mainline and, this would allow more room for other stuff.

I spend most of my adult life working with electronics/electrical control wiring. I am not concerned about how to wire up the loop.....I have read up on that one.

My question to the group would simply be; when is it not a good idea to use a reverse loop? 2nd Question....if a person is comfortable with the install/wiring, why wouldn't they use the reverse loop?

[DanB80]

if a person is comfortable with the install/wiring, why wouldn't they use the reverse loop?

Usually its real estate, a reverse loop can take up a considerable amount of room compared to a turntable or the old 0-5-0. The bigger/longer your cars and trains, the larger the loop needs to be.
Layout purpose could also be a part, for your own scenario that sounds like you want to railfan your trains it sounds like a great plan. But again if real estate is an issue loops eat into a lot of area that could be used to industry operations or something.

Thats my logic anyway. (my own layout does include a revers loop as part of the mainline run)

[MRLdave]

I'm struggling a bit with an auto reverse issue myself right now........on a wye, not a loop, but the principle is the same. The issue with the wye, is you can't make the legs of the wye long enough for a complete train. My problem is cars with metal wheels...... every time the metal wheels hit the insulated gap, it triggers the auto reverser. If the locos haven't cleared the reversing section it causes issues. The REALLY big issue is Kato passenger cars equipped with lighting (or wiring for lights) because the trucks have both wheels on the truck connected thru a bar, so when the first wheel triggers the reverser, the second wheel is still on the other side of the gap, so you get a short thru the truck. The same could potentially occur on a loop. I fixed (if you can call it that) the problem by going to plastic wheels which wasn't an issue because I had no plans to install lighting......... I left one wheel on each truck of the observation car metal so the marker and drumhead work, but you can't short thru the truck. I keep thinking there has to be a better way, but haven't figured out what it is.........

[NtheBasement]

Not sure what the geometry is with the wye but see if throwing it with a DPDT switch that controls polarity of some section of your layout would solve it. I do this with a balloon track (clearly not what you have), no auto reverse needed.

[Stu]

Turn-a-rounds at each end. One wall is a little over 15' and the other wall is a little less than 10'.

It sure seems to me that have an auto reverse loop at each end would sure make a lot of sense...

Reverse loops make a LOT of sense for that type of operation AND your description of the room you have. I have two RLs and enjoy operating my layout immensely and couldn't live without them. You can see my layout track plan in my build thread in my signature.

You could simply sketch out your plans on a piece of paper and "follow two trains around" and see what effect the RL or RLs would have on how you an operate. RLs can change meets into passes immediately without having to move anything on the tracks by hand.

Good luck, have fun.

[MRLdave]

Nthebasement.....thanks for the idea, but your idea doesn't solve the shorting issue, which sends my base unit into alarm. The trucks on the Kato passenger cars have a metal strip (just like the pickup in locos) that connects the 2 wheels on each side, so no matter how you throw the reversing, you end up with one wheel on the truck on each side of the insulated joiner creating a short. On a side note, you have to leave the contact strip in, because it has the bearing cups for the wheels.......if you remove them, there's nothing to hold the wheels.

Majordadsage........you could do the balloon loops in a little over 2.5 feet if you do 11" radius curves. You haven't mentioned what kind of cars you are planning to run......11" radius may be too tight if you want to run cars longer than 50'. Also, doing the smaller radius will make your loops smaller, which will limit the length of trains you can run. Of course you can extend the loop by running the exit track parallel to the entry track for a ways before reconnecting, but at some point, you end up having to make the decision between the extra track to simply make the layout a dog bone, vs the cost of the switches and auto reversers.

[WP&P]

I personally don't think that reversing loops are actually all that necessary or desirable, though in my youth I certainly did whatever I could to fit them into my layout planning. The real-world challenge of getting locos to the opposite end of the train for a return journey adds a bit of challenge to operating the layout. Where I can see them being a requirement is for some form of "off-world" staging, where you want to have a train end up facing the right way for its next trip out of staging. But there are other ways to handle staging, and one should consider whether the same train should be seen both coming and going. A crack passenger train might indeed need to exit staging with the same consist running both directions across the layout, but manifest freights might really only be flowing in one direction (similar trains with different consists going the other way).

An early version of my layout was somewhat designed around a mine turn, which would take empty hoppers from the yard out to various coal mines along the route, trade them for loads, then return to the yard. I had a reverse loop planned at the end of this run. The plan for the current iteration, however, eliminates this loop, opting instead for a runaround maneuver that trades engines and caboose positions. This is far more typical for how real mine turns operate, at least aside from modern flood loaders that are set up on big loops so the whole train can run through at once.

[P-LineSoo]

I have a reverse loop on my layout. It's on the innermost route on the old section, and it makes itself purposeful by following the industries next to the river in the town of Liberty Bluff. There's even a siding off of it. So it doesn't take up real estate, because it is part of the real estate and is not only a reverse loop, but a necessary and vital line to business, to keep the railroad running.

[Stu]

I have a reverse loop on my layout. It's on the innermost route on the old section, and it makes itself purposeful by following the industries next to the river in the town of Liberty Bluff. There's even a siding off of it. So it doesn't take up real estate, because it is part of the real estate and is not only a reverse loop, but a necessary and vital line to business, to keep the railroad running.

So true. A RL doesn't have to be "lost real estate or sidings." One of my two RLs is an "over" above the ground level RL where on the ground level I added two sidings. One of them is facing and one trailing as any train comes through.

An important part of any RL, single or double re: operations overall, is that you have a lot more flexibility when it comes to servicing any spurs because you can change facing and trailing depending on the train's direction. It may not be prototypical operations but it certainly works for model railroading. Unless you are modeling an actual proto and that is your goal.

[The Ol' Curmudgeon]

I built an N scale layout in the '90s (a John Armstrong trackplan) that had reverse loops at each end. Although portions of each loop were visible, they were not obvious as being reverse loops. Ultimately, they functioned as "serial staging" (compared to "parallel" staging yard tracks).

So, is there a place for reverse loops in layout design? You bet. But if they're out in the open, at least try to disguise them, as they're rarer then hens teeth in North America.

[OTFan]

I think the choice the OP is discussing is between a reverse loop at each end of a L shape layout with a single mainline in between them, or a turnaround balloon at each end of a L shape layout with a loop of track that goes all the way around.

In this case, the reversing loops mean you could go with one mainline track through most of the layout. That's an advantage if you're trying to focus on that one main line, and it matches the look of the area you are modeling better than two lines (each side of the loop) running through most of the layout. I might go a little narrower that 30" deep benchwork for the single line portion of the layout in that case, but there's nothing wrong with 30" deep benchwork either.

The disadvantage of the two reversing loops is more to wire up and potentially troubleshoot, though you said that is not a major concern. As @MRLdave implied, you'll want to keep your train length - or at least any part of the train with metal wheels - shorter than the length of that reversing loop. You can still run a train that's several feet long though, so that may not be a problem.

[bigfoot21075]

I have waffled back and forth on Reverse Loops. In the end it makes my layout much more usable. I am going to try to disguise them with scenery and the like. I like you, have the room and THINK I can make it look good. I may not be able to run 100 car sets through them but I am fine with that.

[ssoysal]

A reverse loop is a way to turn the trains around. As others posted, you may or may not need it based on your operations. Here are some examples for where you may not want to have a reverse loop:

• Modeling a stub-ended terminal in steam era, you probably don't need a reverse loop there and a turntable is probably more realistic.
• Modeling modern era freight-only railroad where diesels can face either direction so there's no reason to flip any equipment around.
• When you have a really short mainline run due to space limitations, and you want to make turning the train around at the end of the line as time consuming (read:more fun) as possible. What WP&P was alluding to with the mine train operations.
• You have a true point-to-point layout.

That being said, it's usually not a bad idea to have some way of turning equipment around without picking it up. Turntables, sector plates, and even cassettes are space-saving ways to do that.

Keep in mind that if you have a dogbone layout (loops at either end with a mainline track between), there's a high chance that you will end up with two reversing loops at either end unless you have a double mainline and you are super careful to avoid crossovers.

[P-LineSoo]

Here's the reverse loop on the old section of my layout. By not making it a literal loop, where the radius is the same, and instead adding some distance in straight and natural looking curving sections, it isn't so blatantly there just to reverse trains. Mine, IMO, looks natural and like it belongs there to serve industries.

reverse.jpg

[sid]

my thoughts (witch arnt worth nuttin ) is the steamers need to turn around ,diesels' do not need to turn around and if your running steamers then you need a turn table or a Y thingy...... ok i shut up now....

[MRLdave]

I plan to make my staging yard (yet to be built) a reverse loop under the main layout. The loop will be about 45 ft. long with 5 sidings on the inside for storing trains.......that should be plenty long to deal with all the possible issues. It will also allow a train to disappear for a fair amount of time as it journeys down and back up from the staging yard.......a run of about 140'. I plan to automate the loop so that when the autoreverser trips, it will throw the turnout to rejoin the mainline. I don't have any loops on the main layout, although I have 2 wyes. One wye is where the track to staging connects to the mainline, which allows me to send trains coming out of staging either east or westbound. The other is where my yard joins the mainline.......the yard is on a peninsula. Again, this allows me to sent trains out of the yard, either east or westbound.

[jhn_plsn]

I think most people don't use the reverse loops at each end as it reduces mainline length. It can be a challenge to disguise but having the mainline run through a scene twice yet separately just adds to the mainline and likely train length. One could also simply have a double main line with loops at each end without any connection, but it would visually have the same effect as two reverse loops. If it were me, and it's not, I would use the blobs as grades and have the mains meander separately. The lower main may have a station, junction, switching area on one end(leg) while the upper would have a similar(yet different) feature on the other leg of the layout. In my mind this creates more opportunities for scenic interest.

[Doug Gosha]

My old layout had reverse loops (it was also a two-level). Not automatic but I have always enjoyed having to remember setting switches and all that, manually, so the trains run without mishap, in spite of mistakes, on my part, often.

My current layout doesn't have them (just two big ovals for the mainlines) and I find I sometimes miss that aspect of running trains, especially when I want to see trains running in both directions around the ovals.

Doug