3 Rail to 2 Rail Locomotive Conversions

I think it would be easier to buy 2 rail rather than converting 3 rail locos. I believe 2 rail is predominantly DC powered and insulation of the locomotive wheels is different. Maybe someone on the forum has done it and has a different perspective.

Ron H

@Ron H posted:

I think it would be easier to buy 2 rail rather than converting 3 rail locos. I believe 2 rail is predominantly DC powered and insulation of the locomotive wheels is different. Maybe someone on the forum has done it and has a different perspective.

Ron H

I do know 2 rail AC has been done, but the trade off would be that the engines wouldn't be able to run on track that is DC-powered.  But that wouldn't be a problem for me since I'd be the only one doing O scale within 15 miles since as far as I know, the rest of the model railroaders are in either HO or 15" gauge live steam.

Easier to go 3 rail to 2 rail than the other way around. Two rail wheelsets usually come one side insulated. Obviously all 3 rail wheelsets would have to be swapped.

Three rail loco and truck frames are usually narrower to accommodate the thicker wheels. At most you can shim the axles. Going two to three rail you likely have to mill the frames. Been there, doing that.

Pete

I bought wiper material from a forum member here (Rod ?). He sells pre-cut strips. I bend them as needed and cut the extra off. Right where the wipers touch the back of the wheels, I use a punch on the back side to create a slight dimple. That helps reduce friction there.

Yes, a lighted or sound equipped car can run on 2 rail AC. If it's designed for DC only, you simply add a bridge rectifier. Plenty of those posts in the electrical forum here about converting to LED lights.

All equipment must have insulated wheels on at least on side for this to work. So converting old engines that weren't meant to come apart easily, can be quite a chore. Those are better left alone unless you really desire one.

@Norton posted:

Easier to go 3 rail to 2 rail than the other way around. Two rail wheelsets usually come one side insulated. Obviously all 3 rail wheelsets would have to be swapped.

Three rail loco and truck frames are usually narrower to accommodate the thicker wheels. At most you can shim the axles. Going two to three rail you likely have to mill the frames. Been there, doing that.

Pete

How do you fabricate your pickups?

Justin, I am going two rail to three rail so I just added pickup rollers. Usually two rail engines have wipers on the tires on the insulated side. i would use phosphor bronze or beryllium copper for the wipers. Both are spring temper. Since this is the two forum I will post details later on a 3 rail forum.

Pete

@Engineer-Joe posted:

I bought wiper material from a forum member here (Rod ?). He sells pre-cut strips. I bend them as needed and cut the extra off. Right where the wipers touch the back of the wheels, I use a punch on the back side to create a slight dimple. That helps reduce friction there.

Yes, a lighted or sound equipped car can run on 2 rail AC. If it's designed for DC only, you simply add a bridge rectifier. Plenty of those posts in the electrical forum here about converting to LED lights.

All equipment must have insulated wheels on at least on side for this to work. So converting old engines that weren't meant to come apart easily, can be quite a chore. Those are better left alone unless you really desire one.

Is the wiper material brass?

@Norton posted:

Justin, I am going two rail to three rail so I just added pickup rollers. Usually two rail engines have wipers on the tires on the insulated side.

Pete

Thanks!

1) How are the pickups fabricated and mounted?

There are several ways to do this. I like the way John Sethian does it. You can read about it in his thread about his PRR Baldwin Sharks here:

https://ogrforum.com/...el-legacy-prr-sharks

2) Can 2 rail lighted rolling stock run on 2 rail AC-powered track.  If not, what would have to be done?

I believe some can and some can't. I think newer 2 rail lighted rolling stock (such as the Atlas CZ cars) can run on AC or DC. Older stuff may be DC only. For the ones that are DC only a simple rectifier circuit is all that is needed.

Steam conversions will be very expensive if you are machining drivers.  A cheaper way would be to see if Pat (Harmon Yards) can find a 2 rail chassis to mount underneath your 3 rail boiler. He is a 3 railer who has done this in reverse many times. I think it would most likely be cheaper to buy a factory 2 rail locomotive and install the Legacy electronics in it rather than convert a 3 rail Legacy steam locomotive. There are other factors involved such as if the locomotive is available in 2 rail but rest assured there is a lot more available in 2 rail than most people think. It's up to you to decide which way is the best for you.

As for diesels if you have MTH diesels with the 2/3 trucks converting is a piece of cake and the cost is minimal. If you don't have the 2/3 trucks then it can still be done but it is more difficult. There are several ways to do it but the easiest way is (in my opinion) to change the truck to a 2 rail truck if possible. If not possible perhaps someone like Pat can convert it but again it would most likely be cheaper to buy the 2 rail diesel and install your electronics in it.

All opinion. I could be wrong on any or all of this!

@Justin Acuna posted:

Is the wiper material brass?

I think it is usually bronze phosphor.

@Hudson J1e posted:

1) How are the pickups fabricated and mounted?

There are several ways to do this. I like the way John Sethian does it. You can read about it in his thread about his PRR Baldwin Sharks here:

https://ogrforum.com/...el-legacy-prr-sharks

2) Can 2 rail lighted rolling stock run on 2 rail AC-powered track.  If not, what would have to be done?

I believe some can and some can't. I think newer 2 rail lighted rolling stock (such as the Atlas CZ cars) can run on AC or DC. Older stuff may be DC only. For the ones that are DC only a simple rectifier circuit is all that is needed.

Steam conversions will be very expensive if you are machining drivers.  A cheaper way would be to see if Pat (Harmon Yards) can find a 2 rail chassis to mount underneath your 3 rail boiler. He is a 3 railer who has done this in reverse many times. I think it would most likely be cheaper to buy a factory 2 rail locomotive and install the Legacy electronics in it rather than convert a 3 rail Legacy steam locomotive. There are other factors involved such as if the locomotive is available in 2 rail but rest assured there is a lot more available in 2 rail than most people think. It's up to you to decide which way is the best for you.

As for diesels if you have MTH diesels with the 2/3 trucks converting is a piece of cake and the cost is minimal. If you don't have the 2/3 trucks then it can still be done but it is more difficult. There are several ways to do it but the easiest way is (in my opinion) to change the truck to a 2 rail truck if possible. If not possible perhaps someone like Pat can convert it but again it would most likely be cheaper to buy the 2 rail diesel and install your electronics in it.

All opinion. I could be wrong on any or all of this!

Thanks for that thread.  Is there a way to tell which cars can run on ac/dc and which are dc only?

The way to think about it is in 3-rail the center rail is hot and the outside rails are ground and not insulated from each other.  In 2-rail the rails are insulated from each other regardless of AC or DC.  Also remember that in a single car or locomotive you cannot mix and match which side is insulated as it will create a short unless there is insulation between the wheel sets.  

2-rail dead rail is easier, but as I know people are going to say it is SO much more expensive.

@rdunniii posted:

The way to think about it is in 3-rail the center rail is hot and the outside rails are ground and not insulated from each other.  In 2-rail the rails are insulated from each other regardless of AC or DC.  Also remember that in a single car or locomotive you cannot mix and match which side is insulated as it will create a short unless there is insulation between the wheel sets.  

2-rail dead rail is easier, but as I know people are going to say it is SO much more expensive.

I've heard of BPRC and it does sound appealing.

Some avenues of thought, ….the juice for some of us is the build itself,…..so if building locomotives & rolling stock is your thing, then there are some routes you can go to swap existing equipment over,….You can have drivers machined for 2 rail use, it’s involved, and the truly economical way to achieve this would be to machine the parts yourself. You also could hunt for full 2 rail chassis to swap out of your 3 rail locomotives…..I, like the others above swap 2 rail to 3 rail, and my preferred method is the full blown chassis swap, as this gives me something of value to resale when I finish my project,…..not to say what want to do is impossible, but you will have a road to hoe…..

Pat

@harmonyards posted:

Some avenues of thought, ….the juice for some of us is the build itself,…..so if building locomotives & rolling stock is your thing, then there are some routes you can go to swap existing equipment over,….You can have drivers machined for 2 rail use, it’s involved, and the truly economical way to achieve this would be to machine the parts yourself. You also could hunt for full 2 rail chassis to swap out of your 3 rail locomotives…..I, like the others above swap 2 rail to 3 rail, and my preferred method is the full blown chassis swap, as this gives me something of value to resale when I finish my project,…..not to say what want to do is impossible, but you will have a road to hoe…..

Pat

If I do end up going into 2RS, then I'll probably be machining tires, which for me should be fun.  I like building things.

My 2 cents. My layout is set up to run straight DC with MRC Control Master 20s. It also will power up with AC for DCC. Additionally, with a few quick changes, I can run TMCC on AC on one or both of the two existing blocks. I do have 2 rail Atlas and Weaver locomotives that run on TMCC, All MTH are PS3 and 2 rail, they run on DCC and there are a lot of engines in the collection that run on DC. Some of the engines are getting slowly changed over to DCC as time and want permit. Lastly, there is one "dead rail" engine that runs on a battery using radio control. That does just fine regardless of the power. It does taking flipping a few electrical switches to make it work. Jeff Lang's large 2 rail layout ran on DCS when I was last there. I do have a DCS system but not have wired in.

Good luck.  -Al

@Justin Acuna posted:

Thanks for that thread.  Is there a way to tell which cars can run on ac/dc and which are dc only?

Not that I know of by just looking at a car. Looking up information from the original importer may give you the answer.

That is so awesome that you have the skills to machine your own drivers. I would definitely like to learn how to do to that someday. Can it be learned from a book or do you suggest I take a class at a local Vocational Technical HS?

I think the AC/DC and TMCC/DCC discussion may be over complicating.    Most all models, now, 3 rail and 2 rail,  use permanent magnet motors (DC motors), I think.    What separates the operating system is the electronic receiver board in the locomotive.    2 wires from the track are input to the control board, and the 2 wires from the board go to the motor.    If 3 rail, one track wire comes from the center rail, and one from one of or both outside rails.    If 2 rail, one wire comes from each outside rail - there is no center rail.    I think whether TMCC or DCC, it works that way.   

If newer models have DC motors, they will not run well, or probably not at all on AC, unless the signal is offset which DCC can do if desired.

As for car lighting, again it will be the same, 2 rail or 3 rail, just a difference of where the pickups are.   

Basically converting diesels, and cars from 3 to 2 rail is relatively easy - sometimes making pickups gets tricky.   Sometimes finding axles the right length is a chore.     But basically it is generally changing pickups and wheelsets.   Generally it is easy to take these things apart and reassemble them.

Converting steam locos is much more complicated.    The mechanisms have all the rods and valve gear.    That must be removed and reinstalled.    Steam loco drivers vary all over the map and finding the right ones can be very difficult.    There are some machinests around that will convert the original drivers.    Rod Miller as mentioned above may do this work.    These are very skilled craftsmen and the work requires special tools such as lathes and quartering jigs and wheel pullers.    It is not a cheap process.

Many years ago Weaver offered its 2 rail engines with the option for AC TMCC control. I had worked on a friends 2 rail layout and built a system powered by AC and TMCC. Many of the engines we ran were Weaver AC TMCC 2 rail. But he also had a good collection of DC engines, many older. I put in some DPDT double pull double throw switches for power to the different main track loops and yards. I could switch between AC TMCC and DC power. I used a heavy duty TMCC engine control board with the DC engine outputs wired to the track leads. When we wanted to run a DC engine we flipped the switch to DC power. The AC power supply ran to a board mounted TMCC engine control and the DC output leads to the motor instead were wired to the track. Worked well! you could control AC or DC engines from the Lionel TMCC remote. Here are photos of the set up. #11 and #22 were the TMCC address #'s for running DC.

Also on a 3 rail Brass Steam engine I had I wanted it converted to 2 rail. A friend had his specialist friend that did conversions to the change. He cut each metal spoke of the main drivers on one side and glued them back together so insulated. Then changed all the other wheels.

@rdunniii posted:

The way to think about it is in 3-rail the center rail is hot and the outside rails are ground and not insulated from each other.  In 2-rail the rails are insulated from each other regardless of AC or DC.  Also remember that in a single car or locomotive you cannot mix and match which side is insulated as it will create a short unless there is insulation between the wheel sets.  

2-rail dead rail is easier, but as I know people are going to say it is SO much more expensive.

and they are wrong ! they are paying more for their Lionel electronics , than starting out with dead rail, and if you like track power , or want both its a simple flick of a switch

I have done a small amount of converting - if you can machine your own drivers for steam, the rest is dirt-easy.  Electronic components have no idea whether they are fed from three rails or two. 

But boy is this getting complex!  I have the feeling that soon either the circuitry will be obsolete or it will start to fail, and we 2-railers will be getting locomotives for cheap.

Dead Rail ought not to be expensive.  Radio Shack was selling model cars with full radio control of everything for thirty five bucks, including transmitter and batteries.  One would think Lionel could do that with starter sets.

Steam 3 Rail to 2 Rail convertion .   Its hard to see , but this is the insulated side. Pecos River Brass Baby Hudson.       cTr...( Choose the Right )

Stephen, that is a beauty!  ...if the internet is to be believed I understand the class 3460's were some of the biggest 4-6-4's ever built too, I have heard that PRB's factory two-rail versions had some issues, how do you like the converted version you have here.  Regardless it's gorgeous!

WOW!!

@aoslapas posted:

My 2 cents. My layout is set up to run straight DC with MRC Control Master 20s. It also will power up with AC for DCC. Additionally, with a few quick changes, I can run TMCC on AC on one or both of the two existing blocks. I do have 2 rail Atlas and Weaver locomotives that run on TMCC, All MTH are PS3 and 2 rail, they run on DCC and there are a lot of engines in the collection that run on DC. Some of the engines are getting slowly changed over to DCC as time and want permit. Lastly, there is one "dead rail" engine that runs on a battery using radio control. That does just fine regardless of the power. It does taking flipping a few electrical switches to make it work. Jeff Lang's large 2 rail layout ran on DCS when I was last there. I do have a DCS system but not have wired in.

Good luck.  -Al

That's really cool.  How complicated was it to set up? 

@prrjim posted:

I think the AC/DC and TMCC/DCC discussion may be over complicating.    Most all models, now, 3 rail and 2 rail,  use permanent magnet motors (DC motors), I think.    What separates the operating system is the electronic receiver board in the locomotive.    2 wires from the track are input to the control board, and the 2 wires from the board go to the motor.    If 3 rail, one track wire comes from the center rail, and one from one of or both outside rails.    If 2 rail, one wire comes from each outside rail - there is no center rail.    I think whether TMCC or DCC, it works that way. 

If newer models have DC motors, they will not run well, or probably not at all on AC, unless the signal is offset which DCC can do if desired.

As for car lighting, again it will be the same, 2 rail or 3 rail, just a difference of where the pickups are. 

Basically converting diesels, and cars from 3 to 2 rail is relatively easy - sometimes making pickups gets tricky.   Sometimes finding axles the right length is a chore.     But basically it is generally changing pickups and wheelsets.   Generally it is easy to take these things apart and reassemble them.

Converting steam locos is much more complicated.    The mechanisms have all the rods and valve gear.    That must be removed and reinstalled.    Steam loco drivers vary all over the map and finding the right ones can be very difficult.    There are some machinests around that will convert the original drivers.    Rod Miller as mentioned above may do this work.    These are very skilled craftsmen and the work requires special tools such as lathes and quartering jigs and wheel pullers.    It is not a cheap process.

D you know where one would buy a quartering jig from?

Northwest Shortline sells a quartering tool/jig.  

@bob2 posted:

I have done a small amount of converting - if you can machine your own drivers for steam, the rest is dirt-easy.  Electronic components have no idea whether they are fed from three rails or two.

But boy is this getting complex!  I have the feeling that soon either the circuitry will be obsolete or it will start to fail, and we 2-railers will be getting locomotives for cheap.

Dead Rail ought not to be expensive.  Radio Shack was selling model cars with full radio control of everything for thirty five bucks, including transmitter and batteries.  One would think Lionel could do that with starter sets.

I think it's less that Lionel could offer them than they don't want to.  But that's just IMO.

@swrr posted:

Northwest Shortline sells a quartering tool/jig.  

Thanks!

@Stephen Bloy posted:

Steam 3 Rail to 2 Rail convertion .   Its hard to see , but this is the insulated side. Pecos River Brass Baby Hudson.       cTr...( Choose the Right )

Man, that is a sweet ride you got!  What size lathe did you use for the job?

In respect to the PRB Hudson, I don't knew others experance, but I found there was a weekness in the frame which Ive strived to address. I may also, get rid of the tork arm motor mount?

@Stephen Bloy posted:

In respect to the PRB Hudson, I don't knew others experance, but I found there was a weekness in the frame which Ive strived to address. I may also, get rid of the tork arm motor mount?

Is it a structural weakness?

I have both PRB hudsons and have had no frame issues as of yet. But, they don't have a lot of run time. I plan to convert all my steam to RC.

This is my first,

@Ron H posted:

I have both PRB hudsons and have had no frame issues as of yet. But, they don't have a lot of run time. I plan to convert all my steam to RC.

This is my first,

What RC system are you using?

I live in Australia, and the lath I use is a" Sheraton " manufactured in Melbourne I think? The truth is, its a copy of the American  " South Bend "     The PRB model is a very nice model, and Im pleased to have it, I saw a potential  problem and fixed it, just incase .  The R/C or Blue Tooth - Wi-Fi ( 2.4 GHZ ) is a solution Ive also exploured.       cTr,,,,( Choose the Right )      https://youtu.be/FCZLToxtEtA

I know NWSL makes a quartering jig for HO scale.    I don't know if they do one for O also, I have never see one.     I think some of the custom machinests  have made their own.    

Until recently, most 3 rail locomotives were not very good models, so modelrs interested in getting scale locos were not interested in converting them.     That has changed a lot.    However, many of the ones done in 3 rail have also been done in 2 rail.  

PS, "recently" is relative and for us old guys could be 10-15 years!

@prrjim posted:

I know NWSL makes a quartering jig for HO scale.    I don't know if they do one for O also, I have never see one.     I think some of the custom machinests  have made their own.  

Until recently, most 3 rail locomotives were not very good models, so modelrs interested in getting scale locos were not interested in converting them.     That has changed a lot.    However, many of the ones done in 3 rail have also been done in 2 rail.

Yes, the easy way to be to sell what I have and start over...but I like challenges.

I have the NWSL O quartering jig,…..a little fidgety until you get the hang of it,….their crank pin cups I find to be sloppy on most of the wheel sets I’ve worked on,…I’ve long since machined various crank pin cups with better fitment/alignment….I’ve even made cups for MTH products, and use the jig on captured axle frames…..I use an inexpensive arbor that I bought and modified solely for the NWSL jig,….having everything locked down frees up your hands to position stuff for the pressings….I’m not sure if NWSL still produces it or not….I’ve had mine for 20 some odd years now…..

Pat

@Stephen Bloy posted:

I live in Australia, and the lath I use is a" Sheraton " manufactured in Melbourne I think? The truth is, its a copy of the American  " South Bend "     The PRB model is a very nice model, and Im pleased to have it, I saw a potential  problem and fixed it, just incase .  The R/C or Blue Tooth - Wi-Fi ( 2.4 GHZ ) is a solution Ive also exploured.       cTr,,,,( Choose the Right )      https://youtu.be/FCZLToxtEtA

What size is your lathe?  I've heard some people say that you need nothing less than a 12" lathe, others have said they got by with a 6" lathe.