3 Rail to 2 Rail Challenger Challenge

I'll be following this thread closely.  I have a lot of interest in this subject and have yet to see a detailed explanation of how to accomplish this task.

 

Good choice of locomotive!

Guys,

Check out Joe Foehrkolb's Baldwin Forge website.  He does this sort of conversion on a regular basis and has a power point tutorial on his site.  

 

Jim

 

 

Converting any 3 rail steam model to 2 rail requires reworking of the locomotive's drivers.

As you will soon see,  a good lathe and well equipped shop will be required to accomplish the conversion you wish to attempt.  Finding a set of pre-made scale 2 rail Challenger drivers that can utilize the Lionel rods etc. is probably more difficult than re-machining the driver castings with scale tires.  Except for the Lionel 0-6-0t conversions I have done, and an MTH P&LE Berkshire, when the owner asked for Lobaugh drivers to be machined and fitted to the model, I have always used the driver centers that were manufactured for the model.  Once you get the original  hi-rail drivers machined, insulated, and re-quartered on shorter axles the hardest part pf the job is finished.  The hi rail driver tires are not useable.  I make new tires from carbon steel tubing. 

 

The rest of the conversion job can be relatively easy.  I almost always use NWSL wheel sets for tender, pilot and trailing truck wheel sets.  In the case of spoked trailing wheels, I re-machine the wheels to a scale profile and insulate them for 2 rail operation.  Precision Scale Co. does offer some ready made spoked trailing truck wheel sets.  My above mentioned web site shows the 2 rail conversion process in some detail.

 

Best of luck with your project!

 

Joe Foehrkolb

Baldwin Forge & Machine

 " Basically, I will be sitting here with tools in hand and the engine sitting on a work bench and waiting for instruction collectively from the forum "

 

  As part of the collective my first thought would be to tell you it's not a job for a newbie. Unless you are an experienced machinist with proper equipment you'll be dollars ahead to farm the drivers out to a pro. If you actually are a machinist the thread could provide a good outline of what's needed but I doubt there are many inexperienced readers who could pull it off? ......DaveB

I don't know.  What you say is true without a doubt.  However, everybody is a newbie the first time they try something.  I'm guessing the idea here is to help people over the hurdle of uncertainty when trying something new.

 

But you will need a lathe and know how to operate it you are going to turn your own tires and so on.  So it is true that tools and experience would be ideal, but for most of us it will have to be tools and some guts.  And I don't have a lathe.  Yet.

 

Jim

 

 

Well, yeah.  But you cannot wait for somebody else to give you a step-by-step - you just have to dig in.  You will make mistakes, of course, but you will also learn how to recover from them.

 

You cannot do this stuff on an Unimat or other jeweler's lathe - a 6" Atlas is probably a rock-bottom minimum.

I started out machining drivers on a 6" Atlas lathe over 30 years ago.  For the past ten years I have been cutting rough driver tires from steel tube stock on an old 13" South Bend and doing the finishing work on my 9" South Bend.  Recently I picked up a South Bend "Heavy 10" lathe and will be setting it up to operate as soon as the weather warms up as it will be set up in my garage.  If the heavy 10 can efficiently perform the cut off operation, the 13" lathe will be sold.  I traded the 6" lathe to a fellow years ago for a Max Gray PRR N-1 2-10-2 after I had acquired the fully tooled 9" lathe.

 

I can do the cut off work for the tires on the 9" lathe but it is a much slower process.

 

Converting a 4-6-6-4 takes me about 15 to 16 hours start to finish, without reinstalling the electronics.  I do not do re-install the electronics and the boards normally have to be removed to get to the mechanism and sometimes to get to the tender truck mounting screws.  I recently converted a Lionel C&O 2-6-6-2 model that had the steaming whistle etc.  All of that stuff was removed and it takes some time to get it all out without damaging anything.  As a first step, you might open one of these engines up to see what you would be dealing with just to start the process.

 

I started out doing much simpler models that were not loaded with circuit boards.  I also machined several sets of rough cast iron driver castings for old outside third rail models and some scratch built locos.  I developed the driver machining techniques that I use on those projects.   If I wanted to learn to do this kind of work and had the tools and skill set, I would start with a simpler model like a Lionel camelback 10 Wheeler or K Line Mikado.  There are also plenty of old driver castings out there to practice on.  If you can machine a driver from rough castings, you can rework 3 rail drivers.  Once you have the techniques down, it just becomes your time spent in the shop.

 

I don't think I can say anything else that would be useful to you.  O yeah, measure twice cut once!  There was, at times,  a lot of scrap metal in the trash can next to my lathe in the early days.

 

Best regards,

 

Joe Foehrkolb

Baldwin Forge & Machine

This could prove to be educational.  Doing this sort of work falls under the heading of obvious to those that have done it before and this exercise could well hi-lite the pitfalls that most do not see or understand.

 

Please provide lots of pictures and text.

 I was going to post the step by step instructions the other day for you.

Here's what I did with my MTH Allegheny.

1) disassemble loco

2) send just the main driver assembly to Joe F

3) figure out later on that it would have been cheaper and easier to let him do the whole job!

 He did a great job on the tires and she runs like a champ. The learning curve on making reliable power pick-ups alone, is enough to keep me from trying this again!

 

I find this subject very interesting even though I don't have the skills or the tools to do this kind of work. When I first got into O scale 2 rail I didn't know about OSN and I needed some locomotives converted. I found a fellow named James Hanson on the internet      and he converted 4 locomotives for me. His work was excellent. When I was in a club I saw the work that Joe does and of course his work is excellent also. These are the only two guys that I know of who do this type of work professionally. I think it's important that others also learn how to do this type of work. What if Joe and James retired? Who would pick up the slack?

There are a couple of articles in the O Scale Resource magazine in the past year that may be applicable to this.  The May/June issue has an article by Glen Guerra on machining driver centers.  And the November/December issue has an article by Fred Oakland about 2-railing a New Haven electric.  The issues are the same really whether dealing with a steam locomotive or an electric or diesel.  Wheels, gauge, insulation, and power pickup.  The latter article focuses less on the machining as it uses ready to go replacement wheels.  But it has quite a bit of information on the electrical aspects of the conversion.

 

Jim

Great information .

 

So what is the minimum size lathe to be able to machine O Scale drivers?  The largest driver in O Scale is a scale 84" (7'), which is 1 3/4" in O Scale.

 

Bob2 says at least a 6" Atlas.  Joe mentions at least a 9" Southbend.  Does anyone know what lathe Glen Guerra is using as is shown in his article in the May/June issue of O Scale Resource magazine?  Others have mentioned that O Scale drivers can be machined and finished using a Sherline lathe.

 

Would a 7 x 16 lathe be able to handle this type of work?

 

Steve

 

 

 

 

 

Steve

 

 

Steve,

If the lathe will swing the driver diameter you are working with, theoretically a small lathe can do the job. However it will be a slow process compared to using a larger and more rigid machine. A seven inch lathe should do the job easily. I use collets to hold a lot in my work in special mandrels I made to work on loco drivers. They allow for a quick setup and consistency in driver diameter and true running on the axles. Finding tooling for some machines can be tricky. South Bend tooling seems readily available on the second hand market.

Joe

Having stopped by Joe's place and been introduced to an overview of the intense detail that goes into 3r to 2r steam conversions it is quite a bit more skill than a car kit or a B.T.S. lumber mill.

 

It is not just the machine shop of tools and special gizmos but the hard learned tricks and work-a-rounds that specially talented folks like Joe acquire over hundreds of conversions and many years of practice.

 

This may become an informational 3/2 thread but I would expect it to be somewhat introductory  in nature.  Not to be discouraging, just a reality check.

It is just a different skill set - it is just as challenging to superdetail a Lobaugh kit.

 

I have an 11" Sheldon and a 9" South Bend.  Neither is truly adequate, but I do not do more than a half- dozen tires in a year.  I run the cutoff tool in as far as I can witho ut stopping the lathe, cut off with a hack saw, then do the back with a gentle cut after the tire is pressed on the driver.  This can be a challenge with the insulated driver, which is mostly held with Loctite - you do not want to introduce much heat.

 

The heavy 10" South Bend will be marginally better than the 11" Sheldon , but Joe will find that the 13" is the one that saves him time.  In fact, I have given some consideration to ordering tires from Joe, since I find machining them to be a bit tiresome.

 

I do not have the luxury of using Leadloy - I use iron pipe, which does not machine quite as freely.  I also use as many pre-purchased tires as I can, stying away from nickel-silver and plated brass when I can.  Check withJoe and Bob Stevenson for prices and availability, if you are using a small lathe.  The Unimat can be used to trim the brass driver castings, although even that can be painful.

 

Opinion - machined my first driver in 1961.

Although I'm not into O scale two-rail, I do look forward to this thread.  I have a Sears/Atlas 12 x 36 lathe that I have used to machine various parts for my clockwork trains on occasion, and I am always eager to learn new tips and techniques for this type of work.  Even though our interests are at opposite ends of the "O" spectrum, I'm sure there are many things I can learn from observing the conversion process.

 

My thanks for posting the thread and the participation of everyone involved.

Pretty exciting TimDude

I will be watching in person and here.

Hi:

 

I converted a Williams (Samhongsa) brass Hudson from 3 rail to 2 rail.  The hardest part was making the O-Scale tires.  I used an older Unimat lathe.  It uses a sewing machine motor and it is small.  I only haven a 3 jaw chuck.  Removing the Tinplate tread was easy.  It was quite a chore to build the 6 tires from steel bar stock.  Took forever.  The wheels on the insulated side were turned down more to allow the insulation to fit.  I used thin clear plastic to separate the tires from the wheels.  The middle set of drivers were originally blind, so I left them alone.  If I remember correctly, the original had traction drivers.  The pilot and trailing trucks were relatively easy as well as the tender.  I simple made polymer bushings to insulate.  I believe the engine was purchased new for less  than $200.  This was a few years back though.  I had no plans other than a sketch of the tires dimensions that I made up based on standard O-Scale flanges. I did use a set of dial calipers though.

 

Thanks...   Tom

 

Tom, that looks great!

I'm looking forward to seeing the progress Timdude...keep us posted and I wish you success with the project.

Tim Dude,

 

Since you original post you have not commented further about this project.  One additional thing to consider about this project has occurred to me.  Most of the large Lionel 3 rail scale steam locomotive models that I have worked on and converted to straight 2 rail DC came from the Lionel factory with a two pieced stamped steel drawbar assembly harking somewhat back to their toy train mentality.  The difference being that Lionel uses a photocell transmitter and receiver attached to the drawbar pieces to send signals between the electronics in the loco and tender.

 

When I convert these models to 2 rail DC this drawbar and photocell circuit is removed and an insulated drawbar is fabricated from Micarta and a drawbar screw and threaded pin are installed in the rear of the loco frame and the front beam of the tender to attach the new drawbar in a conventional manner.  Since the tender trucks on a 2 rail loco normally pick up power from the fireman's side of the loco (left side) and the loco picks up power on the right side, a steel drawbar would cause a short if the tender trucks were not insulated from the tender frame.  Also, I am not sure how Lionel grounds their circuit boards to the loco and tender frames.  You will have to study the electronics carefully or perhaps someone following this topic has found a way to deal with this and can give you some insight.

 

Converting the model initially to 2 rail DC and then adding DCC and aftermarket sound would be much easier to do, although I do not install DCC.  However, I have read about it and it looks fairly straight forward.  If I ever used electronics in my locos it would be DCC equipment.  I don't want anything in my locos that I cannot troubleshoot or replace/repair myself.

 

Best,

 

Joe Foehrkolb

Baldwin Forge & Machine

I 2- railed an MTH Hudson.  Wound up with a new frame, new cylinders, Lobaugh drivers, new gearbox, and re- calibrated flywheel.  The MTH Proto-2 sound system required opposite polarity to work, and I do not know why.  I set the locomotive up with insulation left - the O scale standard - and wound up with it on the right.  I also wound up with all wheel pickup in the tender, using spring-loaded plungers.  Some day I shall get a factory reset, so I can hear the bell and whistle.

Thanks everyone for all the comments so far. I finally found some time to get some pictures of the specimen. I had also bought some spare assemblies for this project. This post is being done with my phone so I can take pictures, I will post more when I get back on my pc.

More pics - tender

And we're off!

Good show Tim!

More pics - engine

 

My thought is to start with the engine pilot and trailing truck and the tender truck as these don't need a power pick up so they should be good with simple insulated wheel assemblies, right?

You guys have mentioned NWSL wheels, are we worried about specific wheel cross section profiles or is that somewhat standard. Also, I think I know the wheel diameters but how can I be sure? What is the best reference material for that kind of information? I don't have the money to go buy every Challenger book ever published.

Keep the input coming.

Tim Dude,

 

Assuming your conversion will be to Standard O Scale and not P-48, I almost always have used NWSL 172 tread wheel sets with blunt axles to convert 3 rail trucks to 2 rail.  If requested I will install 145 tread wheel sets but stopped doing that when I got a complaint that a model was derailing on a large eastern club's layout due to their imperfect trackwork.  I changed the wheels to 172 tread and the problem went away.  Therefore, no more 145 tread wheels going on models that I do unless the owner take responsibility for their trackwork.

 

You may need some spacer washers, brass on the insulated side and fiber on the insulated side of the wheel sets to keep them from having too much lateral motion.  Kadee sells 50 packs of fiber washers in 0.015 and 0.030 inch thickness.  I brass washers in quantities of 100 from McMaster Carr.  Go to their website and check them out.

 

Assuming you have a good caliper, measure the hi rail wheels at the base of the tread where is meets the flange.  This will be the rolling diameter of the wheels.  For example:  0.750" is a 36" wheel. You will probably need 40 or 42 inch wheels for that large tender truck, perhaps also on the trailing truck and the pilot truck might use a 33 inch wheel set and still clear the frame on curves.

 

Joe Foehrkolb

 

Pilot wheels on 3 rail scale models are often undersized and usually their diameter can be increased to near the correct wheel diameter.  You will have some playing room because of the oversized flanges on the hi rail wheels.  The new scale wheel sets cannot touch the loco frame in operation or you will experience short circuits.

 

NWSL offers flush axle wheel sets for pilot trucks.  I generally just chuck a standard blunt axle wheel set in my lathe and cut the axle ends of making them into flush axles.

If you are only doing this one model, purchasing the flush axle set makes sense.

Oops...brass washers on the non-insulated side!

 

Joe

Thanks Joe, 

Yes it is just going Standard O not P48. 

Hey everybody, sorry I haven't posted in a while. I bought the Kratville book on the Challenger and read it cover to cover. Then I ordered some wheels from North West Short Line. The ones for the pilot truck are back ordered so I will carry on with the others. Pictured is the NWSL 42 inch 145 tread wheel next to the original Lionel tender wheel set.

I have a pretty good idea of how I am going to do the power pick ups (thanks Jim). More to come.

The Krattville Challenger book is excellent-everything a guy needs to know and then some!

 

Keep us updated, was thinking about this thread the other day.

Finally some progress to report.I was able to use my cheapy gear puller (left) to pull the Lionel wheels off their axles. The NWSL insulator bushings (right) fit the Lionel axles perfectly. Using my Arbor press I pressed the new wheels onto the old axles. I sanded down the face of two of the old wheels to get my gauging correct. I used a stock Atlas wheel set to establish gauging for these wheels. I then went out and bought some small plastic washers from the local hardware store, painted them black and pushed them on the outside of the wheels. Later this week I will do the tender truck and then reassemble the tender for a side by side.

 

 

I sanded 

Here is the tender truck assembly.  I really fought this one. I got one set with a wobble to it and trying to fix it ended up wearing out the insulator bushings. My fix was to go get some Evergreen plastics tube, item number 225, to use as a spacer between the wheels. Took some trial and error to get the exact dimension, this time it was 1.055 inches. So the stack up still has the little plastic hardware store washers on the outside of the wheels. I will brush paint with flat black paint before final assembly.

Keep it up TimDude!

I missed this!

Okay on to the pilot truck, and my first real problem. The wheels themselves were pretty straight forward.  After installing them the first time I realized there would be to much side to side clearance to not hit the brake shoes. So I installed more of those hardware store plastic washers, one each behind each wheel. I am much happier with the end result. The problem is the brake shoe assembly wil not fit. While trying to figure out a solution, I thought I would look in the Kratville book and see what the prototype looked like. On page 94, a series of pictures of 3975, there is a clear picture of the front truck assembly and there are no brake shoes? In fact throughout the entire section of the later Challengers I don't see and evidence of the Lionel style brake shoes. Why did Lionel put these on their model? Is there something I am missing?

Trailing truck finished. Same basic process as the trnder truck only I don't need the little plastic washers as these axles are contained in plastic bushings that snap into the truck assembly. 

Thanks TimDude! Great photos too

You are now up to where I am with my Lionel FEF.  I don't remember whether I had to drill journals, but I just installed Lobaugh wheelsets in all trucks.