Pondering MTH Proto 3/2 steam options

Pulling the hi-rail wheels outward to clear scale flange ways might cause some mechanical problems with your side rods, etc. I'm actually somewhat surprised that at some point hi-rail wheelsets didn't evolve to a narrower tread with a larger flange since larger equipment isn't designed to run on O-31 and O-42 curves anyway.

Another option would be to have the backs of the drivers machined so the drivers would be narrower, then have the tire fronts machined down to match. You'd have the same flanges, but you could seat the wheels farther out without interfering with the side rods and superstructure. Essentially, you'd be 2-railing the locomotive with large flanges.

The data I've collected so far indicates that the scale-wheeled MTH Hudsons, switchers, Mikados, and oddly enough, the Big Boy, can operate on 36" radius (O-72) 2-rail track. That might be an option for you. I have no data on the 2-8-0's but they're probably also compatible with 36" radius. Anything below that radius (or if you're planning on big Northerns, 2-10-4's or a UP 4-12-2) and you'll have to go the 2RHR route.

Thanks Matt. I had hoped you would chime in. I read your posts from a few years ago and they were similar to what I have found. That is very good news on the Hudsons and Mikados. I think they were listed as 42"r but having validation of 36"r opens up enough possibilities for me I think. I love Northerns, but probably don't have the space for them right at this moment.

You're welcome. I was seriously tempted to get that 3rd Rail Northern in 2-rail, but I just didn't see the 54" minimum radius in my layout future. So I bought the hi-rail version instead. Of course, now that I've done that I'll end up buying a house with a huge outbuilding that can support 72" radius and I'll be kicking myself that I didn't buy that scale-wheeled engine.

By the way, if you get an MTH scale-wheeled locomotive, make sure you use Kadee 805's or 740's with the standard length shanks. On the 6-axle diesels, shave 1/8" off the back of the box and it will clear the mounting boss for the hi-rail coupler on the power trucks. The standard shank gives you more swing than the 806.

I have another option for you.

MTH recently announced 2 rail Scaletrax. I expect their engines will run on the track just peachy.

Scaletrax may not be perfect to scale but it's a lot closer than all the other track out there.

I'm going to the 3 rail Scaletrax for that very reason.

If you stick with the Premier line the flanges are a lot smaller than the other lines. I have a UP 4-12-2 high rail version and it runs fine run fine on code 148 and the flanges are pretty small. I did however change the tender wheels with NWSL scale wheels and brought the side frame in just a bit. It looks a whole lot better.  Since I just started buying the scale wheel versions, but I would buy the high rail version if the engine is big enough.

I need to get my bigboy wheels sent to get them machined for two rail. When I can do it I am going to have them leave in the blind drivers and just isolate them so I can run a bit tighter radius if I need. But I have figured out a decent way to get a pretty big radius.  I have the same thought as you about this and see no reason it won't work.

Ralph 

I would go any way you feel you need to. I always felt that 2 rail was the best but as I got deeper into the O guage/scale debate I feel it better to build your railroad around the room you have and enjoy  your trains whether they have deep flanges or not. I have scene post of layouts done real nice in guage trains as there is alot of choice out there now especially with Atlas cars and their detail. So if one runs his trains around a tight turns but has produced a nice layout scene it should suffice making O a rewarding hobby.

Hi Ralph. Thanks for the info. Does your 4-12-2 take Atlas 148 turnouts ok? I wonder if it really is hit or miss? If I could be confident that the hi-rail models would work on code 148 then I would just go that route. That's an expensive gamble though. My experience has been more in-line with Matt's findings. I too don't understand why MTH didn't just thin down the wheels a bit and gauge them properly. If the scale wheel models run fine on 3 rail track then what's the harm of thinning the hi-rail wheels a bit? I wish I could just by the scale wheels and put them on myself. The MTH parts department is pretty clueless though. I couldn't even get a replacement fixed pilot for a diesel. Probably no hope of getting a set of scale wheels. I wonder how difficult it would be to remove the flanges from the center drivers? Is that something that could be done on the model or best to remove them and put them on a lathe to turn them down?

jonnyspeed, I understand you're looking for facts not opinions. But, I can't help myself.  I just gotta hope it will help you to consider the following.

About 3 years ago I started migrating to 3-Rail Scale.  Went through a never ending set of potential compromises and accommodations to try and fit things together.  It wore me out and was very frustrating.

So, I switched the layout to 2 rail using Atlas O track and turnouts and never looked back.  All is serene now.  I have the NMRA standards to rely on for couplers, wheesets, track, etc. etc.

For example, take a look in the NWSL catalog at the wide variety of 2 rail wheelsets available and compare this to the miserable selection of 3 rail wheelsets.  Not to mention how much better the 2 rail sets look.  

And these days 2 rail engines from Sunset/GGD and Atlas O run great right out of the box just like 3 rail engines. Probably MTH, too, but I'm waiting for PS3 engines for DCC operation.

The diesel engine minimum radii aren't that much bigger.  Same for smaller steam engines.  But, I admit min radius is a big factor for larger engines and I set mine at 60 in.  The tradeoff for me was in the same space less track and fewer turnouts of higher numbers. 

My engines and cars roll like velvet on my track and thru my turnouts. too.  Not all that clunking.

Good luck whichever way you go.  It's all fun.  Hope this helps.

No worries Austin Bill. I appreciate your input. I've been thinking long and hard about this and I've decided that I will be sticking to 2-rail standards. Code 125 or 148 track, running DCC or PS3. There are just too many variables to keep in my head to worry about. I'll stick with smaller steam and most diesels that will operate on 36"r for now. Down the road I will have the opportunity to add wider radius track when I finish my the main room in my basement. If there is some larger Steam that I just have to have, I'm not afraid to machine down the center drivers if necessary.

Thanks for all the input guys.

I know for sure they will run on code 148 Atlas or ME. I have both and have no problems. As for Atlas switches I wouldn't see why they wouldn't go through them fine. I have hand laid my switches so I haven't ran them through an Atlas. I really don't think you would need to turn anything down just to make them work. I'm pretty sure that MTH took that into account having seen where they test run stuff.

Now I see you mention code 125, that they won't run on. If you go with code 125 then you need scale wheels. Definetly go for PS3 then you won't have the polarity issue as the PS2. PS3 can pick up the polarity in either direction.

I think your going the right way with all this and have fun. I also decided to go 2rail and I'm much happier I did. Hope some of this helps.

Ralph

Hi Ralph,

Thanks for your input. Just so I'm clear... you have had success with running the Hi-rail wheels through code 148 turnouts?  I'm not set on code 125. It just happens that I have the ROW parts and ties to build 6 #5 turnouts. No big deal though. I don't mind the look of code 148 if it gives me a little more flexibility.

I saw it stated elsewhere that the European O Gauge market is almost exclusively finescale, (hence the absence of any efforts to make European equipment in the RailKing line). That alone would explain the near-universal availability of scale-flanged MTH equipment overseas. In fact, the hi-rail versions of these trains are probably intended  mostly for the North American market.

---PCJ

Jonnyspeed,

Only one potential problem stood out to me from what you have written and that is regarding the use of ROW parts. I think the ROW frogs might have tolerances too tight for 3 rail flanges.

RailRide, thanks for the info. I don't mean to hi-jack this thread but I wonder why European O Gauge market is almost exclusively fine scale? According to the catalog all the (or at least the ones I looked at) fine scale versions require larger curves. Maybe they are mostly collectors or maybe they for the most part participate in modular or club model railroads? Just curious.

Austin Bill, no need to wait any longer. Almost all, if not all, new MTH engines have a DCC decoder built in. Any engine that is PS 3.0 has DCC

Hudson J1E.  Yep. I just received my first PS3 engines.  Two Rio Grande GP-35's.  Scale wheels.  Fixed pilots.  Switch selectable NMRA DCC or MTH DCS.  Switch selectable 2 rail or 3 rail operation.  Center rail pickups included in the box.

Came without pumpkin couplers.  I installed Kaydees.  Very straightforward with 2 Micromark shims.  Runs very well on DCC with a full suite of very well thought out DCC functions using all 28 keys on my NCE DCC remote.  Even has smoke.   

Plan to test it in 3 rail and 2 rail DCS operation on my stationary running base later this week and then some local 3 rail layouts.

Evening gents, I seem to remember Mike Pitogo (where is he anyway) had Joe Foehrkolb  do an MTH Triplex to all scale wheels and never did hear anything more on this project. The pictures I remember in the article involved replacing all the driver tires and re-machining them to 2 rail. WOW, that had to have been some tedious work doing 3 four axle sets of drivers and all those rods. Wonder how it turned out. I'd ask Mike but he seems to be on some sort of hiatus from the forum. Bill

BasementBill, well Mike Pitogo recently replied to the thread about Joe G so maybe he is back on the forum?

Austin Bill: Those Rio Grande units are very nice engines. I always liked that paint scheme. Good luck with them. Do you plan on changing the wheel sets when you run it on 3 rail track? Most of my friends in this hobby are 3 rail guys so when I get my layout up and running I am going to pick up some scale wheel sets to keep on the side. If they have a PS 3.0 diesel that is 3/2 capable then all we have to do is switch the wheel sets, the DCS/DCC switch and the 3R/2R switch and they can run it on a 2 rail layout. I was going to buy an FM Trainmaster but the only that wasn't available with scale wheels was the one I wanted (the CNJ).

Do you plan on changing the wheel sets when you run it on 3 rail track

Hudson J1e.  No, I will stick to the scale wheelsets.  These engines run silky smooth through my 2 rail Atlas O #7.5 turouts and with 60 in min radii no problem there either.

From following the forum on similar topics- thanks to those who have tried all this and have reported on results --- THANKS --  I am expecting that when running on 3 rail t-rail Atlas O, MTH Scaletrax and Ross/Gargraves with decent radii that the engines will behave.

And again from the forum I expect that the scale wheelsets will slightly drop on the t-rail larger numbered unmodified turnouts from the same vendors. 

The great unknown for me at this time is the degree to which these engines will run on our modular club's K-line Shadow Rail tubular track but which has forgiving Ross switches and 60 inch  radius (0120) curves.  I'm hoping that the broad curves will cut me some slack and that the scale wheelsets won'r roll off the tubular track  -- at scale speeds pulling a coal drag.

We'll see.  That's part of the fun of it for me. 

They probably won't do well on "round-top" rail as the flanges don't have something solid to push against in curves, plus the narrower wheel tread isn't really enough to "sit" on top of the track. My Hudson "sank" in a section of track at the club layout where the gauge was too wide, while all the standard hi-rail equipment had gone through fine for years. I've since fixed that section, but it hints that tubular track could be problematic as the top of the rail is further out than the gauging of the track.