Adapting for myself HO 4x8


DakotaLove39

Always Improvising
Rosston%20Joelberg%20%20Holly%20RR%20CSX%20branch%20line.jpg

Model Railroader Magazine said:
Mainline Run: 32 Feet
Minimum Radius: 17"
Minimum Turnout: No. 6 (Main), No. 4 (Yard and branch)
Maximum Grade: 3.5%

This is a track plan I found in the latest special issue from Model Railroader named the Rosston, Joelberg & Holly. The original designer completed his layout as a CSX coal line in West Virginia.

Now, here is a slight problem. MR seems to be pretty good about depicting what trains are able to roll on the layout in question. On this one they show three 6-axle diesels hauling coal and grain trains. Are larger diesels like SD75's and Dash-9's able to run properly on a 4x8 HO layout without using 18" radius curves?

Second, I am pretty strongly set on modeling midwestern stuff. My 4 locos are BNSF, and seeing that the layout was originally designed for coal operations I had the idea to base mine on my local flavor; Minnesota iron. BNSF being the most likely rail hauler according to my MNDoT freight railroad map.

The MN Iron Range is pretty rocky and hilly in its own right, but not mountainous like West Virginia. If I were to reduce the grades to perhaps 2.0 or 2.5%, would I be running into clearance issues with the over-under locations? I can't think of any reason why I would have husky-stack cars running on this layout but anything is possible I guess.

Last, how practical is it to have a staging area built below the "tabletop"? I've seen many small layouts where the staging tracks are put on a collapsible section that hangs off one end, but I can't really afford such a thing even with it being 4x8'.
 
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No. Even SD40-2's might derail some cars attached to them. Usually people use B-B engines (GP60, RS11 four axle max engines), and 50 foot or shorter cars. I myself have use an 18"R as a minimum on my N scale layout.
 
i think that was also in an article sometime last year, and if i remember right, he was using some modern 6 axle ge stuff. ac4400 or dash 9's.
 
i think that was also in an article sometime last year, and if i remember right, he was using some modern 6 axle ge stuff. ac4400 or dash 9's.

Yes, the header picture shows an older 6-axle GE loco hauling a coal string. On the next page, you can see the same GE unit now hauling a grain train, and two Dash-9s on the bridge above hauling coal.

Leva said:
No. Even SD40-2's might derail some cars attached to them. Usually people use B-B engines (GP60, RS11 four axle max engines), and 50 foot or shorter cars. I myself have use an 18"R as a minimum on my N scale layout.

The concern is about the mainline, not the sidings or branch. When it's time for the bigger locos to take a break, the fueling/sanding is on a siding which is nice and straight.

I have a GP38-2 for the switching work (and a barely running SW1200 needing work). The other two are an SD75M and a SD9. I know for a fact the SD9 can handle 18"R curves, I would just rather not have any such tight curves on the mainline.

I really just don't know what the usual minimum radius is on 4x8.
 
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I'm working on laying out a 4' x 9.5' (it's the room I have at the moment) layout myself, and I'm trying desperately to keep the mainline radii at 22 inches.
 
My shorter six axle locomotive works ok on my 18" curves but if anything is wrong it is the first to derail.

My Bachmann Alaska 4 axle is my most reliable.
 
Rosston%20Joelberg%20%20Holly%20RR%20CSX%20branch%20line.jpg



This is a track plan I found in the latest special issue from Model Railroader named the Rosston, Joelberg & Holly. The original designer completed his layout as a CSX coal line in West Virginia.

Now, here is a slight problem. MR seems to be pretty good about depicting what trains are able to roll on the layout in question. On this one they show three 6-axle diesels hauling coal and grain trains. Are larger diesels like SD75's and Dash-9's able to run properly on a 4x8 HO layout without using 18" radius curves?

The MN Iron Range is pretty rocky and hilly in its own right, but not mountainous like West Virginia. If I were to reduce the grades to perhaps 2.0 or 2.5%, would I be running into clearance issues with the over-under locations? I can't think of any reason why I would have husky-stack cars running on this layout but anything is possible I guess.

Last, how practical is it to have a staging area built below the "tabletop"? I've seen many small layouts where the staging tracks are put on a collapsible section that hangs off one end, but I can't really afford such a thing even with it being 4x8'.

Did the article mention if the author hand laid the track or used commercially available products?

I'm thinking the north side of the mainline might be an overall 22 radius, but that curved turnout buried in the tunnel looks problematic. The tightest Walthers curved turnout uses an 18 inch inside radius and a 24 inch outside radius, which would require the remaining curve of the mainline, to average less than 22 inches.

The south side mainline looks way tighter than 22 inches, with the outermost track being the branchline. It looks like it has a 22 inch radius.

The steepest grade looks to be on the south side branch, which is probably where the layout's grade is 3.5%. I doubt if you could make it any less than that. The mainline crosses over itself twice. The loops appear to have enough distance to possibly have only a 2- 2.5% grade for the clearances.

IIRC correctly from the photos in the mag, that mine scene is pretty dramatic because it is very high above the other tracks. My guess is that most of the steepest grades reside on the branch line.
 
Dakota:

I did something today that might have a bearing on your engine/radius situation.

I have at least a couple of HO Bachmann SD40-2 diesels (6 axles each) that I added 5 ounces to make each total 22.5 ounces. I wanted to see what their amp/volt draw was, and these meters are currently connected to an L-shaped loop that has 16" (yes, that's sixteen inches) radiuses, so I ran them pulling a 68-car train around the loop only once. [The results came out .4 amps (i.e. four tenths of an amp) and 5 volts - in my experience these are minimal draws.]

However the point here is that the 6-axle Bachmann SD40-2s will run easily around 16" radius track BUT they sort of max out my visual "credulity meter" - i.e. they look pretty silly. On the other hand I'm visually comfortable seeing them run around the 22" radius loop, and kinda okay when running round the 19" radius loop.

I generally use 4-axle diesels on my trains - for me they vissually fit comfortably in the curves and pull well - but the SD40-2 engines are my favorites (I rode them many times in the mid 1970s as head end brakeman so I naturally HAVE to run them! :)

In summary, in the case of your radiuses and engine lengths you'll have to make your own decisions.

And by the way I wonder what percent of 6-axle HO engines will actually take "sharp" (18" or less) curves without derailing.

DougC
 
Did the article mention if the author hand laid the track or used commercially available products?

I'm thinking the north side of the mainline might be an overall 22 radius, but that curved turnout buried in the tunnel looks problematic. The tightest Walthers curved turnout uses an 18 inch inside radius and a 24 inch outside radius, which would require the remaining curve of the mainline, to average less than 22 inches.

The south side mainline looks way tighter than 22 inches, with the outermost track being the branchline. It looks like it has a 22 inch radius.

The steepest grade looks to be on the south side branch, which is probably where the layout's grade is 3.5%. I doubt if you could make it any less than that. The mainline crosses over itself twice. The loops appear to have enough distance to possibly have only a 2- 2.5% grade for the clearances.

IIRC correctly from the photos in the mag, that mine scene is pretty dramatic because it is very high above the other tracks. My guess is that most of the steepest grades reside on the branch line.

Yes, the Mine section tops out at 7", whereas the town would be 0". The drag up there would be pretty steep, I think. I mean even the line running below the mine is 3".

The article I have doesn't state if it was handlaid or pre-fab track.

I also agree with the tunnel turnout, in my mind I didn't have a turnout there and had pushed it closer to the town. I have never liked the idea of turnouts buried in tunnels.

I appreciate the technical help, fellas. This isn't something I'm going to be jumping on right away. I don't yet have room for even a 4x8, so I'll be starting my railroad ventures with a smaller switching layout for the short term future. I would love to build something like this later though.
 
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Have any of you thought about using 20-inch radius sectional track? That's what I have on my 13' 7" x 14" layout to accomodate loops at each end of my folded dogbone with a peninsula and leaving enough room for aisles. I can get at least some Proto2000 six-axle diesels running on them, though I haven't tried some of the more modern models. Shinohara (sold by Walthers) makes various radii sectional track, including the 20".
 
I would love to build something like this later though.

Build it now if it is what you want.
This plan is basically the same plan as the gorre and dapheted. Been built successfully by many people.

Good luck.
Steve
 



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