Conversion from 2-Rail to 3-Rail - Doable? Practical?

If you have Atlas or Gargraves track, and wide curves, you might be able to get away with slapping some pickup rollers on and calling it good. With tubular track you would probably be looking at installing new driver tires, complete new drivers, or a complete chassis swap.

As far as electronics go it wouldn't be much if any different from installing the components in a 3 rail brass Williams or Weaver conventional locomotive.

@Lou1985 posted:

If you have Atlas or Gargraves track, and wide curves, you might be able to get away with slapping some pickup rollers on and calling it good. With tubular track you would probably be looking at installing new driver tires, complete new drivers, or a complete chassis swap.

As far as electronics go it wouldn't be much if any different from installing the components in a 3 rail brass Williams or Weaver conventional locomotive.

I currently use FasTrack for a floor layout, but was thinking for a permanent layout I would use a combination of Ross and Atlas/Gargraves track. Is 072 wide enough for something like a C&O 2-10-4? I forget that chassis swapping is possible. If I need something like that I might send it to Pat/harmonyards  

That's great to know about the electronics!

If you’re handy, have access to tools, and machines, swapping two rail to three rail is rewarding, and fun,…especially with highly detailed brass steam locomotives…..many avenues to explore, including swapping drivers, swapping entire chassis, or machining tires for 3 rail operations,……this WAS a KTM 2 rail brass O scale IHB 0-8-0 I made into 3 rail using a MTH chassis ……I even took the time to make the tender motor work, and kept the 3rd cylinder mechanics, as this is what makes this locomotive unique,….runs like a champ,…

Pat

@0-Gauge CJ posted:

I currently use FasTrack for a floor layout, but was thinking for a permanent layout I would use a combination of Ross and Atlas/Gargraves track. Is 072 wide enough for something like a C&O 2-10-4? I forget that chassis swapping is possible. If I need something like that I might send it to Pat/harmonyards

That's great to know about the electronics!

If you're planning to keep the 2-rail mechanism and wheels, that 2-10-4 will need more like O100 to O110 curves.  Forget about O72.  Tracking through 3-rail switches can also be problematic for steam locomotives with 2-rail flanges.

To those who have done it, how well do 2 rail wheelsets track on Gargraves track and switches?

The trouble you will have with 2 rail steam conversions is that all drivers are flanged which will severely limit turning radius. I’d thing trying a smaller wheel arrangement to start with like a 2-6-0 or 4-6-0 would yield good results.

Pat, the IHB 0-8-0 is very cool. The tender booster is powered as well? Any videos of it running? I’ve got one of the Rivarossi kits and a motorized chassis from another built up one that someone put a big DC open frame motor in. Runs very smooth and will get TMCC and RS at some point.

I've tried the conversion of 2 rail to 3 and kept getting shorts. Now I RC them.

Atlas three rail track is the only rail head I would consider for two rail flanges but on a much larger curvature.  That wheelbase typically in 0 scale two rail needs at least a 0-108" in my experience.  0-144" preferred.

The die on which GarGraves rail is drawn has worn considerably over the years and the distinct inside edge has diminished significantly over the years leaving a less than desirable inside top corner.  IMO, that large wheelbase would challenge tight GG curves.

I would not consider any currently available Lionel track or any tubular track for two rail flanges.

Using a 3 rail chassis will be a much better path if you can not change out the 0-72" track.  All my opinion.

As mentioned, the 2 rail flanges are iffy at best on any 3 rail track. I’ve attempted to run 2 rail flanges on O99 Atlas 3 rail with mediocre results, so I abandoned that idea whole heartedly,…..My approach when working with a 2 rail scale piece I’d like to run, is to do a complete chassis swap when the parts are available. This is two fold, ……I find it a lot easier to modify the diecast 3 rail chassis to fit onto the brass shell, and then the complete 2 rail chassis can be sold off ( usually for darn good money)  thus, helping offset a lot the costs of the project……Of course, for my projects, shopping around for the “good deal” is paramount to keep the project cost from skyrocketing,……many avenues to explore to 3 rail a 2 rail piece,…this is just one approach I have ….Here’s this IHB 0-8-0 completed, painted, and lettered,….note the clean install from the underneath. Take your time, plan your work, and sneak up on cuts/fitments until you’re happy with your work,…

Pat

Oh, boy ..there is so much in two rail brass l have, for years!, wanted in three rail....McKeen car, Mack railbus, Little River 2-4-4-2,, and the list goes on and on.  I have been stymied by the difficulty of these conversions.  Brass cabooses, if they exist, are an easy conversion.  I am not aware of any brass Colorado Midland, or Florida East Coast/Great Westernl side door cabooses having been made.

Thank you everyone for the comments on track radius, lots of good information and experience to draw on!

@Ron H posted:

I've tried the conversion of 2 rail to 3 and kept getting shorts. Now I RC them.

That reminds me, 2R wheels are insulated. I don't think that's a problem for running a locomotive, but could it be a problem for accessories? In that case I would probably be obligated to do a chassis swap. But let's say that's not a deal-breaker... When looking at some of discussions of converting from 3R to 2R, the topic of wheels would come up because 3R flanges are a little too big for 2R. One suggestion there was to gently sand/grind them down until they were an appropriate size. Going back to the 2-10-4 example above, could I grind down the middle three drive wheels and leave the first and last drive wheel flanges untouched? If yes, I imagine the locomotives could run on tighter radius track than +0100.

@harmonyards posted:

As mentioned, the 2 rail flanges are iffy at best on any 3 rail track. I’ve attempted to run 2 rail flanges on O99 Atlas 3 rail with mediocre results, so I abandoned that idea whole heartedly,…..My approach when working with a 2 rail scale piece I’d like to run, is to do a complete chassis swap when the parts are available. This is two fold, ……I find it a lot easier to modify the diecast 3 rail chassis to fit onto the brass shell, and then the complete 2 rail chassis can be sold off ( usually for darn good money)  thus, helping offset a lot the costs of the project……Of course, for my projects, shopping around for the “good deal” is paramount to keep the project cost from skyrocketing,……many avenues to explore to 3 rail a 2 rail piece,…this is just one approach I have ….Here’s this IHB 0-8-0 completed, painted, and lettered,….note the clean install from the underneath. Take your time, plan your work, and sneak up on cuts/fitments until you’re happy with your work,…

Pat

Pat, that is a gorgeous model! is there a manufacturer's chassis you prefer?

@0-Gauge CJ posted:

Thank you everyone for the comments on track radius, lots of good information and experience to draw on!

That reminds me, 2R wheels are insulated. I don't think that's a problem for running a locomotive, but could it be a problem for accessories? In that case I would probably be obligated to do a chassis swap. But let's say that's not a deal-breaker... When looking at some of discussions of converting from 3R to 2R, the topic of wheels would come up because 3R flanges are a little too big for 2R. One suggestion there was to gently sand/grind them down until they were an appropriate size. Going back to the 2-10-4 example above, could I grind down the middle three drive wheels and leave the first and last drive wheel flanges untouched? If yes, I imagine the locomotives could run on tighter radius track than +0100.

Pat, that is a gorgeous model! is there a manufacturer's chassis you prefer?

Really doesn’t matter,….beings both MTH & Lionel modern 3 rail chassis are just about similar in construction,….I just happen to have a plethora of MTH Premier steam chassis at my disposal, so I work with what I have,…..don’t expect a bolt in swap, irregardless of what ever chassis you may choose,….the key is to modify the 3 rail chassis to the 2 rail scale shell, thus preserving  as much of the precious details that made you want to perform such a swap in the first place……therefore, you’re basically making the 3 rail frame look more and more like a 2 rail scale frame….

Pat

And don't forget - you are going to be converting a thousand dollar brass model into a $100 special hybrid.

I did a Lobaugh Berkshire for a fellow forumite - we jacked up the boiler and put a Williams Mikado engine underneath.  I got to keep the Lobaugh mechanism.

It was a lot more labor than the Lobaugh parts were worth, but it was an intriguing exercise.  I think we were both happy.

A 2-10-4 is more of a problem, but it could be approached the same way.  A thousand dollar brass model, a $900 "donor" Lionel or MTH model, about 20 hours of labor, and you would have a nice $100 model that would go around O-72.  Maybe.

I would keep it 2-rail and put it in a display case.

@bob2 posted:

And don't forget - you are going to be converting a thousand dollar brass model into a $100 special hybrid.

I did a Lobaugh Berkshire for a fellow forumite - we jacked up the boiler and put a Williams Mikado engine underneath.  I got to keep the Lobaugh mechanism.

It was a lot more labor than the Lobaugh parts were worth, but it was an intriguing exercise.  I think we were both happy.

A 2-10-4 is more of a problem, but it could be approached the same way.  A thousand dollar brass model, a $900 "donor" Lionel or MTH model, about 20 hours of labor, and you would have a nice $100 model that would go around O-72.  Maybe.

I would keep it 2-rail and put it in a display case.

Dang Bob,….a whole 100 dollars??….you must be getting generous in your old age,…..nothing brings me better pleasure than to 3 rail y’all’s precious 2 rail brass stagnated display models and run the oblivion out of them,…..save the display cases for the museums,…..but heck, 100 dollar value placed from you!???…that’s a compliment, and I’ll run like the Devil,…😝

Pat

It is indeed a case-by-case situation. Very small steam can squeak through sharper curves -- 36" radius (O-72), but they're an exception. Usually, you're looking at a 42" (O-84) radius minimum for six-axle diesels and small steam; 54" radius (O-108) for medium steam; and 72" radius (O-144) for large steam.

Ironically, the MTH modern "3-2" diesel locomotives can negotiate sharper curves, but the steam locomotives require wider curves that are determined by the number of drivers, driver size, and wheelbase. You also have to factor in having freight cars with body-mounted couplers attached going through the curves, tender/cab clearance, etc. I have a Sunset ATSF 2-8-0 that can make it through 36" radius, but it squeaks through due to tighter tolerances. My Sunset 44-tonner can handle it fine because it's so small. In contrast, my MTH 2-rail ATSF Blue Goose Hudson and 2-rail UP Big Boy (of all things) go through 36" radius just fine (the Big Boy looks silly). I wouldn't try it with a scale-wheeled Northern.

Rolling stock is also a case-by-case situation but it usually relates to clearances in the chassis and coupler swing, plus you need to have good track gauging and flat-top rails (No tubular or FasTrack) for Code 145 wheels to operate reliably. My new rolling stock purchases have generally been 2-rail only and I've been converting my rolling stock to scale wheels and Kadee couplers so I can live in both worlds.

Hey Bob! I think I'll hang a set of pickups on the tender of my 2-8-0 and replace the DCC decoder with a Proto-3 kit.

On a 2 rail steam locomotive, the valve gear is closer to the wheels than a 3 rail model due to the flange thickness. While not impossible, it is difficult, time consuming, and costly  in converting 2 rail steam to 3 rail steam. Many times ones better off waiting for 3 rail mfg come out with the loco than try to convert one.

Pat - not clear what you are saying, but it sounds like you should be ready to help the OP, who wants exactly what you do.

Of course I have no basis for asserting that 3-railing a thousand dollar mantel piece would reduce its value.  I would be happy to apologize for my opinion if posters can show real resale value for such hybrids.

Admittedly, that IHB brass conversion looks good, but I would be surprised if its resale value has not suffered.

@bob2 posted:

Pat - not clear what you are saying, but it sounds like you should be ready to help the OP, who wants exactly what you do.

Of course I have no basis for asserting that 3-railing a thousand dollar mantel piece would reduce its value.  I would be happy to apologize for my opinion if posters can show real resale value for such hybrids.

Admittedly, that IHB brass conversion looks good, but I would be surprised if its resale value has not suffered.

Bob, …I’m just giving you a hard time man,….I mean nothing by it,….your work is always exemplary, and your insight is always top shelf,….but who knows what the value would be…..especially on a piece that’s never been, nor never will be done in 3 rail ……if it’s hacked to death, slapped together, then yeah,…it’s trashed, and that’s that,….I’ve seen plenty of that, …but if it’s done to a level of quality machined parts, perfect fitment, perfect alignment, and most of all, the least invasive to the brass shell, ……but as usual, I’d have to agree with you,…hence the 😝 face,….they probably ain’t worth what they were ……the value in it for me, is the challenge of doing a superior job,..

Pat

@Ryan Selvius posted:

To those who have done it, how well do 2 rail wheelsets track on Gargraves track and switches?

The trouble you will have with 2 rail steam conversions is that all drivers are flanged which will severely limit turning radius. I’d thing trying a smaller wheel arrangement to start with like a 2-6-0 or 4-6-0 would yield good results.

Pat, the IHB 0-8-0 is very cool. The tender booster is powered as well? Any videos of it running? I’ve got one of the Rivarossi kits and a motorized chassis from another built up one that someone put a big DC open frame motor in. Runs very smooth and will get TMCC and RS at some point.

Just as KTM had built that IHB, the motor under the tender is just along for the ride,….I had to remove the 2 rail wheel sets, which are very unique for that truck/motor, and machine a set of Lionel 3 rail wheels to adapt to it,….I can post a video on here of it, I haven’t installed an electronics package in it yet, but I do have it running on a rectifier for testing,…

Pat

"Back in the day", when I first started doing some O-gauge trains, I had my old postwar Lionel.    then I was introduced to scale models, and the lionel just did not look right next to it.    I started building rolling stock kits, I could not afford brass cars.    The only type track I was aware of was 3 rail, but I did learn about Gargraves.    I built a layout using Gargraves flextrack and switches.    Originally I used Lionel trucks and couplers but later converted to Kadees and CLW.

The gist of it all is that as I did more more scale stuff, I found more and ended up with a combination of motive power.    I had a Thomas 4-4-0, and a couple of IMP 0-4-0 that were 3 rail,    But along the way, my wife bought me a brass 2-rail 2-6-0 for our anniversary, and I bought and built an All Nation 4-4-0 kit.  

Converting the 2 rail to 3 rail was extremely easy compared to going the other way.   First, the gargraves track was flat top rail.    The track gauge was good, and the scale flanges stayed on that track just fine.    The switch frogs were a bit sloppy and could cause derailments.   I glued risers to the guard rails to get them high enough to keep the 2 rail flanges aligned.     The biggest issue for me was finding a place to put an E-unit since I used my old Lionel transformers at the time.      I installed roller pickkups on the tenders or on the  bottom plate of the locos depending on where they fit.

I moved on and converted from the Lionel trucks to Athearn trucks which rolled much better.    All the stuff worked on the Gargraves track.

I think the key to a 2 to 3 rail conversion is using flat top track, to avoid have to change wheels, especially on steamers.    With today's power systems, fitting E units that rely on gravity is no longer an issue.      And as mentioned early on, it is going to be a case by case basis.    Bigger locos are going to be more of a challenge.

I wouldn’t call this exercise a rush to go and buy up all the 2 rail locomotives on the planet and start hacking,…..as mentioned, it’s case by case…for me, it’s the desire to have models that’ll never come to be, or if they are, they’ll be so high priced, it’s a sin,…. One example I’m planning on is a NYC Mike H10 class, hopefully the H10b ….they do exist made by KTM,….when I’m buying lots full of parts, I plan ahead, sell off what I don’t need, or never going to use, so my parts are either totally free, or nearly free,…..in the case of the “future” H10b project, I have a complete MTH Premier Mikado chassis, rods, valve gear, motion hangers, the works,…let’s call it a rolling chassis,…..so if I find the right deal on a KTM H10, 700-800 bucks ( which is doable) I can harvest the 2 rail chassis, keep the pilot assembly, and sell off the “rolling “ 2 rail chassis …usually for descent money,……..now I have the ingredients to build a 3 rail H10b, which is a desired model for us NYC modelers, and if all goes to plan, I’ll be in it 6-700 bucks sans whatever electronics package I decide to install,……sure, I could wait for 3rd Rail’s H10 to come out, but I was never crazy about 3rd Rail’s mechanics, so I’d rather have the known proven performance of a captured axle chassis…..that’s my cup of tea,….others will strongly disagree,……the enjoyment part of this hobby for some of us is the challenge of building something that works for your pike,…..for me, it’s all about longevity,…as anybody who’s visited my layout knows, I run trains, and run them for long periods, so longevity is a paramount,……I just can’t see some of that 2 rail scale equipment standing up to 1000’s of hours of run time, and not get worn out, or suffer some kind of major mechanical failure,….even 3rd Rail’s running gear is just too delicate IMO for constant running, …yeah, they’ll run, but maybe a parade lap or two, then back on the shelf,….holding your breath something isn’t gonna fall off while you’re running it,……not for me……all of my brass J1e, and J3a Hudsons sport complete MTH chassis,….toss them on the track, and let them eat,….for hours on end,…….now I have the best of both in my eyes,…super scale detail, and robust drive trains,….albeit the big flanges,…the way to go about a particular swap is to plan, plan, & plan ahead,…..keep a budget in mind, plan for it, have back up plans, measure, test fit, build it better than they did….

Pat

With respect to resale value, I buy every engine with the expectation it will sell for only a fraction of what it did originally down the road. Just about every engine I have purchased that wasn't NIB was discounted from its original MSRP. Not even brass engines are immune to this (although they are more resilient to depreciation). Resale value is not a factor in my mind when I buy a model, brass or not - I am more interested in having a full roundhouse complete with models of prototypes used on a few railroads so I can properly model a given timeframe.

Thank you all for the inputs, I think I will include 2-rail engines in my roundhouse. Worst case scenario, if I change my mind about 3-railing them, I can sell them or put them on a shelf. Thanks all for your help.

@harmonyards posted:

I wouldn’t call this exercise a rush to go and buy up all the 2 rail locomotives on the planet and start hacking,…..as mentioned, it’s case by case…for me, it’s the desire to have models that’ll never come to be, or if they are, they’ll be so high priced, it’s a sin

That is true. I would rather just buy a 3-rail version of a 3rd Rail model but as you mentioned with the H10b, it will probably never be made in 3R by anyone, and the only option then is a conversion from 2R. It's unfortunate, but at least there is an option for 3-railers.

I agree a lot of 2-rail mechanisms have limited longevity.  But do not forget the older models, such as Scalecraft.  Those things come with relatively large flanges, blind center drivers, huge fixed gears, ACDC motors, and often uninsulated (hence cheap and not terribly useful for the 2-rail crowd.  Run forever!

We got thousands of actual hours' use out of an older NWSL gearbox at the museum.  Burned up three motors, and all we did was put ball bearings on the worm shaft and Lubriplate on the gears at each motor swap.

Without incurring any permanent damage, I installed the rudimentary 3R command requirements into a 2R Sunset, PRR J1.   That's about as close to the C&O T1 as it gets. The obvious curve negotiation issues put a hold on any further experimenting, as making 2 sets of drivers blind was, and still is beyond my skill set.  It looks as if the J1 will have a dedicated stall and become a turntable queen.

Bruce

I've posted a couple of threads on three railing two Lobaugh locomotives.

https://ogrforum.com/...-a-lobaugh-berkshire

https://ogrforum.com/...ling-another-lobaugh

and getting pick up rollers into scale trucks

https://ogrforum.com/...ller-in-tight-places

I've also three railed three All Nation steam engines.

I've always used the original mechanisms.  I do blind the center drivers and make new tires for the first and last driving axes.  My drivers have code 172 thickness with and increased flange height of 1/16" (MTH uses this flange height on some of their 3 rail steam drivers).  For the leading and trailing trucks I use 0.075" flange height.  This works very well on my clubs layout, Angeles Gate HiRailers in San Pedro, which uses Gargraves and  Atlas track.  People told me to get these locos around 3 rail curves I'd have to hack away tail beams and the inside of cylinders.  I've never had to do this and my All Nation Mountain and Lobaugh Berk can go through an 072 curve.

I agree that my 3 rail Lobaugh berk might only appeal to me and not have much resale value.  However it is one of my favorite engines to run they can figure out what to do with it when I'm dead