3rl vs 2rl

Alan

 

I would suggest that you start by defining the equipment that you want to operate.  You said...

 

Am looking at Atlas GP15's&MTH GP38-2's for my motive power at present.

 

The Atlas Trainman GP15 has been offered in 2 rail conventional so you would need to add a sound and command system.  If you get the GP15 you can get it with factory TMCC or conventional with swinging pilots.  The two rail locomotive would have 2 rail wheel sets.  I have not changed out wheel sets of fixed pilots on Atlas geeps.  I would want to ask someone who had to decide if either option was a way I wanted to go.

 

MTH has made their GP38 with Proto3 in 2 rail.  By ordering the -2 version you get out of the box AC/DC/DCS/DCC capability with very good sound and speed control.  To make it into a 3 rail scale locomotive all you will need to do is swap axles and MTH makes that easy with their truck design and separate sale 3 rail wheel sets.

 

From a radius standpoint those locomotives could be any four axle road switchers.  Thirty six inch radius would work fine for those locomotives in 2 rail or 3 rail.

 

Do you plan on ever operating six axle diesels?  Any steam or electric locomotives?

 

What sort of freight cars do you plan to operate?  With GP15s and GP38s you are into the era where 50 foot freight cars are on the small side.

 

Do you intend to operate any passenger cars?  If so what locomotives will you have to go with them?

 

You may have rolling stock that, if equipped with body mounted couplers, would need wider radius curves than the Geeps.

 

Then you may want to consider the options for 2 rail or 3 rail and command control on the locomotives you are interested in.

 

Let us know what you are thinking.

 

A few years ago, I made the decision to go with scale-wheeled versions of all MTH diesels I bought. I run them in 3-rail mode at the club for the most part, though I do occasionally pull out some 2-rail Atlas track. MTH charges about $20 more for a scale-wheeled version vs the hi-rail version (both versions can run 2-rail or 3-rail and Proto-3 engines can run on DC, AC, DCS, and DCC); Atlas charges the same for 2-rail and 3-rail engines, but about $5 more for a 2-rail freight or passenger car vs. the 3-rail counterpart.

 

As a practical matter, the only real advantage now for 3-rail is space requirements -- you can run anything made in 3-rail to date on 36" radius (O-72). 2-rail operation requires more judicious selection of equipment. Wiring issues are easily resolved using several products out there -- AzaTrax comes to mind (http://www.azatrax.com).

 

Any layout I build will go both ways since I have purchased a couple of 2-rail switchers. As it stands right now, I've chosen MTH ScaleTrax as the rails are insulated and it has a lower track profile.

Alan,

 

I have replaced all the lobster claws with Kadees on my engines and rolling stock, it takes some effort but if you're the least bit handy with tools it should be not trouble for you.  I have also fixed all the pilots so they don't swing with the trucks.

 

I would say there's more offerings in 3-rail than in 2-rail, but like Ted said you should define what it is you're looking for before deciding.  I model, or at least try to, the old Seaboard Air Line and it's difficult finding anything in that road name AND that's correct.  I bet 75% of my stuff (10 engines and 50 pieces of rolling stock) has been repainted/lettered.  One of the reasons I got out of HO was because, at the time, there wasn't a lot of SAL stuff in that scale either, now I trip all over it every time I go to a train show!

 

There's plenty of 3-rail track/switches available, not sure how many makers there are of 2-rail switches these days that can be plopped down on the layout without having to build or tweak them a bit.

 

I wish I would have looked at the MTH ScaleTrax that Matt mentioned as the Gargraves and Ross track I use looks huge (but ballast can hide a lot of that look).

 

With your space you can go either (or both) ways.  I was thinking the other day that I would like to have a 3-rail loop throughout the entire upstairs room, tied into a 2-rail switching layout.  I could run long freights or passenger trains on the 3-rail loop and have an interchange/yard where I would drop off freight cars and have 2-rail engines do all the switching jobs...best of both worlds!

 

 

O is like HO was in lack of availability years back.

 

THAT is an understatement for sure LOL!!!

 

I don't recall any interference between the Kadee boxes and the trucks, but it might happen depending on which engines you get.  All of my engines have the "tongue" where the lobster claw coupler attached to, I may have Dremeled them off on at least 1 engine.  Being you have to disassemble the engine to a certain extent to add the Kadees and fix the pilots it would be easy enough to take care of these "tongues" at the same time.  Of course, all this means you've altered the engine for life (unless you bought OEM parts to bring it back to original specs).  If you're worried about resale value your target crowd (3RS crowd) is very small at this time compared to the 3-rail crowd overall.  I don't plan on selling mine so it doesn't bother me.

 

The electro-couplers I've dealt with were all plug-in parts, easy to deal with an gets wiring out of the way that may give you problems if left in (frees up some space in the engine also).

 

With 072 and #5 TOs you should be fine, I wish I had used that criteria.  My mainline is 072 curves with 072 switches and 054 on all the sidings.  I could have used 090 curves and much the same track plan.

 

Beware of the "fantasy" paint schemes offered by all the makers, even Atlas and Weaver get things wrong sometimes.

 

You'll find the shims needed to get the Kadees at the recommended height will vary between makers of rolling stock.

 

Also, decals are becoming harder to find in O scale.  Jerry Glow has been good to us by providing a number of "southern" RR schemes.

 

Most of my fleet is comprised of engines running under the MTH PS2 system, although I have a few TMCC engines too.

 

I use DCS, but I also have the new CAB1-L/Bas1-L TMCC system.  All 4 of my steam engines are PS2, I have a Lionel GP9, a 3rd Rail E7, and a MTH Railking RS3 using TMCC/railsounds guts and a MTH NW2 and an Atlas GP9 using PS2 guts.  On the diesels, I really like the TMCC/Railsounds sound, the GP9 sounds great.  I also have a Williams E7 that currently has no electronics (waiting on funding to install ERR Cruise and Railsounds).

 

The only engines I have that did not require a repaint are the Atlas GP9, MTH NW2 and RS3, and the 3rd Rail E7 (I provided them with paint samples to match the Seaboard Mint Green scheme).  I repainted the Lionel GP9 and Williams E7 and all 4 of the steam engines.

 

I also have 9 passenger cars painted for Seaboard.  3 are MTH cars, none of them are accurate cars for SAL, but they look nice.  2 are K-Line Heavyweight cars repainted, 1 is an old All-Nation OBS, and the last 3 are aluminum car bodies from OK Engines mounted on scratchbuilt floors, interiors, ends, and store-bought trucks.

 

The 3 MTH cars are the only pieces I have that still have the lobster claws on them.  I don't run them now, but if I can find a prototype for them I  may repaint them to match the RRs that owned them.  One of the cars is a full-length Vista-Dome, I may end up using parts off it on future rebuilds.  The original cost of the car was around $65.  It came with 6-wheeled trucks and a pair of trucks costs about 1/2 that plus I can reuse the interior, lighting, and ends for other projects.

Why not make the initial decision based on whether you like the looks of 3-rail track or not?  You can adapt from there.  Some just tolerate the apprarance of the track, but others love it.

 

If you feel strongly about reaistic looking track, the other stuff is just details.  If you have nostalgia for three rail track, you will be happier with 3-rail track.  Good luck with your decision.  The key to a hobby is you are supposed to enjoy it, not agonize over it.

Bob2: Thanks for the thoughts.

The last sentence is the key:enjoyvs agonize. I do a lot of that. Of course it has to be the right decision based on information gathering which requires a level of I guess you'd say agony,but back&forth,forth&back is all I do. Added to the fact HO high dollar items just set here with no sales&I'm asking less than what I paid. My eyes water when putting together some O scale couplers under magnification,so I don't know how I'm gonna put together HO couplers.

It'll all work out in the wash,as my late Dad used to say.

Thanks again,

Al

Al,

 

Are these the air hoses you're looking for:

 

http://www.hitechdetails.com/Hoses_O.html

 

I was into HO (last century ) also.  When I decided to get into O I wanted to do it with a laid back approach and not fret over whether or not things were 100% accurate, that's one other reason I chose to go 3-rail.

 

To me 3-Rail Scale gives me a sense of the history and significance of real railroading, yet has the "playing with trains" feel that keeps things in perspective.

 

I do get anal sometimes, but not to the point that I start wishing I had never gotten into the hobby.  It's as much fun to just let a train ride the loop as it is to pretend I'm actually running a railroad.

Thanks Bob these aren't the hoses I'm looking for. What I'm looking for is I think manufactured by Precision Scale Co.(?)
I pulled up their web link 1 time&it showed me a photo of them. They've got plastic hose&brass glad hands. No come to think of it,I hit ebay not their link.
Can you tell me if on Atlas turnouts,if I can use Caboose Industry ground throw switchstands in place of the remotes that come with the O-72 t/o's? The only thing I question,is if the remote powers the frog. If they're like their HO brothers,the switches are fully powered,not rought selective. If Atlas' diesels are all wheel electrical pickup,an unpowered frog makes no difference.
I watched a ballasting video on 3 rail track&switches&that looks REALLY NICE!!! 3 rail's my choice providing I can sell my HO Empire collection.
Thank you,Alan

Your 50 ft length is awesome.  The 15 ft width of your space can become an issue in 2 rail due to the wider radii curves.  Not a show stopper but can turn out to be restrictive.  Much easier to deal with in 3 rail.  Take if from me.  A guy who now has a 2 rail layout in the same space as my former 3 rail layout.  The width being 17 ft. 

He already chose.  He is going 3-rail.

bob2.  Oops!  Thanks.  My comments still hold for anyone else.  If I ever build or otherwise acquire another train room for my 2 rail layout the width will be no less than 24 ft.  For what I'm trying to accomplish my 17 ft. width is restrictive.  The 17 ft. width worked much, much better for my former 3 rail scale layout.  Bill

Alan,

I read your post and your post on the two-rail forum. Is this the effect you seek with Atlas three-rail diesels?



The three-rail models can be converted by purchasing the parts from Atlas. It can be an involved process, though, and you may well have to paint parts (such as the replacement pilots). How it is done also varies from engine to engine. Some use spacers to achieve a full fixed pilot while others use a complete pilot replacement. To run fixed pilots definitely means ditching the toy train coupler, which is mounted to the trucks. No way you can fix a pilot and keep that and run on anything but the broadest of curves (and I don't mean 072). While modelling always involves choices along a continuum, I see little point in fixing pilots but keeping tinplate couplers. 

In any event, if you are interested in Atlas conversions, I think I did an overview of what's involved for some different engines (no GP15s, though).

I have no advice on whether you should go two-rail or three. If I knew today what I know now about the kinds of radii today's Atlas and MTH equipment can perform on, I might well have gone two rail. But I didn't (and didn't get good advice on that). I've toyed with jumping all the way to two-rail. A number of my MTH engines basically are two rail, as is a fair amount of my rolling stock. My Atlas engines probably could be converted to two-rail TMCC with just wheel swaps and power re-wiring, so I wouldn't necessarily have to replace them. I only tolerate the third rail. But I guess I just don't care enough to start all over again. As Bill points out, you have a fair amount of space, and the 15-foot width will easily accommodate diesel-era equipment made by MTH and Atlas (if they ever start shipping engines again). I'll leave to others the debates over sound, control systems, and reliability of two-rail power pick up vs. three. Remember, though, the grass too often looks greener somewhere else. This is a casual hobby for me. I do what I like, make my peace with it and don't worry too much what others think.

Good luck,

RM

There's a key point - it depends upon what one is trying to  accomplish or what your goal is with your layout.

 

I have just about 1/2 that width, but I fully accomplish what I chose to model and meet my goals of having fun within that space.

 

Ted's original response addresses this in part, but time frame/era, choice(s) of operations, geography all come into play to define boundary conditions of what you might do within a set space.

Martin, well put.  Totally agree.

 

For me it's big steam and mainline operations in a 17 X 32 space and I've paid dearly by switching to 2 rail.

 

With the same general schematic and using virtually the same benchwork when switching from 3 Rail Scale to 2 rail I went from a minimum radius of 45 inches to 60 inches.  And from a minimum #5 turnout to all #7.5 turnouts.   Net result is fewer sidings, less mainline and a reduction from about 25 turnouts to 15 turnouts.  But, that's okay.  I'm happy.   Oh and less maintenance!!

Ausin Bill,Rich M.,Bob2,Martin&anyone else I'm unintentionally forgetting here: I finally get some of the finer points I been missing here. I don't know why I was equating "pilot"&"trucks" as being 1 in the same. I guess it's been being in HO so long "pilot" was sedom mentioned,maybe it's just because I'm gettin' more feeble minded,I don't know 4 sure,but last night the "light" finally shown through!! I totally get why swinging pilots will mess up what I'm wanting to do with my couplers. The fixed pilot will be better,but if I don't have sharp curves&have a place to mount the coupler boxes,shouldn't that still work? I'm probably not going to be able 2 have working cut levers on my couplers,but if it's just on my loco's,I can deal with it.

Oh Rich M.,yes that's the look I'm going for in your pic's of the Santa Fe diesels&3rail turnouts. FANTASTIC,is the only word I can use to describe that shot!!!

There's 1 term I'm sure I'm lost on though,&that's the "O-36,48,54,72." I get the O Scale track radius nos like 54"&60" a 60" is the larger brother of it's little 30" brother in HO. But I thought "O-54," was the same as "54" in scale radius just another way of putting it. Here I'm lost.

I've got some other problems. In looking my basemnt over,I get a feeling that with the bigger radius,in that 15-17' width,I'm gonna feel like I'm running Lionel trains again which isn't the effect I'm after. I need space for the larger trains to not seem toylike.

My objective in O scale,is to bring all the scale features of HO,up to O Scale to be duplicated&enlarged:I'm not trying to compromise scale detail here,for if I do,I lost my objective&may as well have stayed in HO. The industries I want to reproduce in O,could be sread out in the lengthof my space I suppose but I've got shelving on both sides of the basement,so deduct roughly 3'ft on each side,plus take off another foot on each side to give a minimum aisle space. That's 8ft off 25,leaving 17' maximum but that's tight,but the wife says the basement's my kingdom,the upstairs,kitchen,well the entire upstairs is her's,no trains or clutter allowed. 12 car grain trains are a must&I'm trying to model a paper factory&chemical factories which would include tankers&boxcars mostly. Grain hoppers are covered nicely by Atlas.

2 layouts I like,all seem to have about 50 turnouts&that's a ton of green stuff for switches alone!! I've got 30 on my 4'x8' HO layout!!

So Bill,your 15 t/o's would fit the price range alot better.

Rich M.,are those turnouts on your Santa Fe layout,Atlas Switches? If so they look great,3 rail regardless.

I gotta run,my wife's gonna be in the dentist's most of the day,but I got some Scale couplers from Protocraft yesterday&they're nothing less that fantastic &work great,never miss a lick,it's like "pulling the pin," on the prototype!!!! yes theycome with "cut levers" too. The only thing that's not a model of my era,(modern),is the "lighteening holes" on the nonknuckle side of the coupler are of a different design&the 2nd thing needed,are attachable upper/lower safety shelves for modern era freight&locos.

My emphasis on my HO & my O scale layout will be switching. Oh I'll still run freight trains of course,but the local freights will be my main concern,as well as grain trains.

Ok gentlemen,that's all for now,off to the dentist.

Thanks again for all your fine inputs&help!!

Al

Switching is my main focus,but while still moving trains,after the switch work is done. The era is modern with CSX&Chessie System is what I model. The geography is the Midwest. Thanks,

Al

With 3 rail no DC + or - issues. Wiring will be easier if you go to loops returning on its self. I would definitely use Atlas track instead of MTH or other track with roadbed. Real Track on a bridge-Tacky! 

Use as wide a radius as you can and use flex track. But, if you do you might want a rail bender if it is 3 rail. With 50 ft length you can use wide radius and still do all sorts of things.

Couple of comments on previous posts.

 

15 ft wide room.  15 ft  X 12 in/ft = 180 inches.  90 in radius X 2 for a 180 in diameter.  A 180 in diameter track half loop will not fit in a 180 inch wide room.  You gotta have some overhang for engines and cars on curves and track radii are usually quoted as track centers.

 

  The "gold standard' for 3 rail is 072 minimum diameter curves as Lionel, MTH, Weaver, Atlas O, Sunset etc design their 3 rail engines to this "standard."  99% of their engines and cars will negotiate 072 curves.  How they look doing so is a matter of opinion.

 

In 2 rail we have the NMRA standards and RP's too lengthy to discuss here.  But, some insight is that Sunset 3rd Rail designs the same engines for 2 rail and 3 rail.  The 3 rail minimum is 072 (72 inch diameter) as stated above.  The 2 rail minimum is 54 inch radius (108 diameter). 

 

As for turnouts I found that where a Sunset 3 rail steam engine would negotiate a #5 turnout the same Sunset 2 rail engine needs a #7.5.  But, this varies widely.  2 rail turnouts are much simpler and more straightforward.

 

I think the wiring for 2 rail is actually simpler than for 3 rail. There are electronic products to deal with reversing loops and turntables that are relatively inexpensive and are very straightforward to install. 

 

I now have a two rail layout in the same space using almost the same benchwork as my former 3 rail scale layout.  The 3 rail minimum curve was 090 (45 inch radius)and the minimum turnout was a #5.  My 2 rail minimum radius is 64 inches and the min turnout is #7,5.  I have less trackage and fewer turnouts for sure.  But, that's okay with me. 

 

I would really like to have 70 " min radii but my 17 ft wide room and what I want to achieve limits me to 64" min radii.  All my close coupled engines and cars negotiate the 64" but don't look the greatest on them.  So, I'll hide most of them.  And the layout is at 53 inches which helps. 

 

Model Railroading plays out under a big tent and there's room for everybody and all approaches.  Just do it!

 

Two more comments:  that 90% number was not based on any data.  I am going to guess that the radius for 90% in O Scale 2-rail is around 65".  I own nothing that won't make it around 70" radius.

 

Second, the wiring of switches is simply not dependent on AC or DC.  If you wire a layout for AC, then decide to go DC, it will work without change to track connections.  Contrary to popular opinion, DC can work on 3-rail track, and AC can work on 2-rail track.

     just a comment- what i don't understand is if you have a passenger car that's 20 inches long and it will go around 045 radius track does it look good doing that? mth and lionel make shorter cars so they run around smaller diameter track and look good doing that. so i think its a matter of what looks good to you not to anybody else.

     with a 15' room you should be able to get a minimum of 84"(0168) which will handle  almost anything and still look great. so whether you decide 2 rail or 3 rail its a matter of what looks good to you and no one else as its your hobby your money and what you are doing for your pleasure.

     what got me out of 3rail initially (mid 70's) was the lack of scale sized locos and cars. then i went back to 3rail because of the sound and availability, but no matter what i bought 3rd rail and scale only mth and lionel that 3rd rail drove me crazier than i already am!!!!

     so i'm going back to 2rail because i like the looks of the 2 rail track and my son who is helping me build the layout hates the 3 rail track.

     but in my opinion blow out the ho stuff and get into o scale you won't regret the choice in the long run.  

I went to 2-rail when a friend taught me to handlay track.   It turned out to be not that hard.   However, the current layout uses flextrack.

 

I find I don't like the looks of the third rail.   It looks better when ballasted and weathered, but still not right.    So I like 2 rail better.   

 

Another advantage is that 2 rail in O scale is mechanically and electrically very similar to HO.   Everything is a little more robust, but all the techniques and theories apply just fine.    There are many more HO modelers than O and everyone else in my group is in HO.    I can ask questions and get help working with 2-rail that I can't with 3 rail.    The only thing these guys remember about 3 rail is the old lionel sequence reverse E-unit!    

 

Radius can still be pretty tight if you are willing to work a little on your equipment.   And you can get a lot more square footage of layout if you think around the walls instead of island type layout.

Thanks so much for the info. I have questions on things here.
 
I was told that all O scale is AC,not DC;if it's DC,I can use my PBL Foreground sound&power system I bought for my HO.(?)
 
I was thinking about buying the DCS system,but if I add Atlas Diesels equipped with TMCC sounds,then as I understand it,I need to buy seperate Legacy or similar systems&join that to the DCS system if I want to use the DCS remote.(?) When using TMCC controllers&or the MTH DCS system,do I still have to buy decoders to install in the Diesels,or if a loco tells that it is TMCC equipped,I assume that's not necessary.(?)
 
Now about turnouts. I was thinking about using the 072 Ross turnouts with Gargraves flex track. I know ZIPP about wiring&as I understand it,Ross t/os come unwired&if you want it wired,that's $5.95 more. I guess the extra money for prewired t/os,would be okay,because I'll save a nice chunk of money on flextrack vs Atlas,no offense to Atlas. If I buy the prewired Ross switches,will I still need to add power to the frogs?
 
Now about fixing pilots on my diesels. 2 diesels I have my eyes on for months now,are atlas GP15s&MTH GP30s. I want GP 40 or 40-2s,but unlike HO,they're not to be found&if they are,they're over the moon in price. The GP15s are available in CSX&Chessie,as are the GP30s from MTH.
How is this accoplished? Is it necessary as long as I use 072 turnouts?
 
If all holds together,I plan on using Protocraft or similiar couplers with cut levers on my locos&rolling stock. They use the same style box as Kadee. I added this in reference to fixing the pilots,to let you fellows know what I'm after in O Scale.
 
Thank you,will be looking forward to your additional input.
Alan

alan,

 

ALL 3 rail is AC power.

 

You can buy ross switches pre-wired if you want to. Most people use gargraves flex track and ross switches for layouts, they both work very well together. You do not need to power frogs in 3 rail. 3 rail track is- BOTH outside rails are ground, and the center rail is power. 

 

You can run TMCC from the DCS remote, you just need to buy a TMCC or a Legacy base and buy the mth cable to PLUG both bases into each other.

 

If a diesel comes with TMCC, you don't have to install anything.

If it comes conventional, then you will need to install tmcc or dcs electronics in the engine. (it's like buying a early blue box athearn and installing dcc & sound decoders)

 

As for the FIXED pilots, you can buy them from mth as SCALE WHEEL version. then you will have to buy a seprate conversion kit from mth for the hi-rail wheels. you will still keep the kadee couplers. you can run fixed pilot 4 wheel diesels pulling small 40' freight cars with kadee couplers on a O42 curve. I had a weaver scale diecast pacific with a kadee coupler on the tender pulling a string of coal hoppers with no problems on a O42 curve.

 

also, www.ericstrains.com eric does great how to videos on just about EVERYTHING.

 

Thanks everybody for contributing to this interesting topic. Could someone please explain a way to convert the minimum radius specified by manufacturers of 2-rail models into a recommended layout width for realistic operation? For example Golden Gate Depot specifies a minimum horizontal radius of 48” for their future Santa Fe Hi-Level cars & Overland recommends a 45” to 49.5” minimum horizontal radius for their SD70ACe. But if I were to design a layout with a dual track main-line what would the minimum width of the layout, horizontal & vertical curve radius & track spacing have to be to provide clearance for overhanging ends & to prevent equipment with low profile from bottoming on vertical curves cresting grades?

 

I do not have room for a layout inside my house but I have an acre of land on my property & I plan to build a structure in the future. I love 21” double-deck passenger cars & twin-stack intermodal freight cars. I might get the newer Lionel Auto racks after I have bought all the intermodal equipment on my wish list. I have the modern 6-axle 2-rail diesel locomotives like SD70MAC, SD70ACe & ES44AC & I plan to buy more of these. I currently have Kadee couplers on my freight cars with Atlas & Protocraft trucks.

 

A distant fantasy would be to electrify the layout since I grew up around electric trains & miss them a lot. Any feedback would be appreciated.

Thanks,

Naveen Rajan

I have a copy of the book, "Lightweight Passenger Car Equipment Diagrams, 1948 - 1972" which I will happily lend for this project.  These diagrams show window placement (but not size), car interiors with dimensions and underbody equipment placements.  

 

Also, a copy of Union Pacific Streamliners.  Easy one stop shopping.

 

ChipR 

Not having either the room, track or cars in hand, I'd grab some large cardboard boxes and my utility knife, and just cut out some mock-ups of both the track curved areas for multiple tracks and some rectangles for cars and just test what spacing works out on the kitchen table.  Low tech, but low cost and minimal stress on the neurons, too. 

 

Take pictures and notes when you have what works and apply that knowledge when you are ready to build for real. 

 

You can do similarly for that bottoming out issue.

 

naveenrajan,

 

48" radius is a 8' curve.

 

in 2 rail it is half of the curve or radius,

48"x 2= 96"

96" divided by 12= 8 feet

 

Also, remember that track minimum radius is to the centerline of track, so a 48" radius curve actually has a working diameter of about 98.5" to the outside of the ties, without any allowance for equipment overhang. 

 

You would be looking at about 110" wide benchwork for a 4' radius curve with safe allowance for overhang. There is no way to nail it down exactly without using templates, or doing an actual track layout

 

 

 

Jeff C