Minimum radius for 2-8-8-2

OK - I've put my Big Boy up for sale on eBay, but I may hold onto my Proto
2000 2-8-8-2. Would it look fairly protoypical on a 30" radius curve, or is
there still going to be too much overhang?
Reply to
Digital Railroader LLC
Loading thread data ...
Well, if you've got it why not just try it? Keith
Make friends in the hobby. Visit Garratt photos for the big steam lovers.
Reply to
Keith Norgrove
Depends upon what you mean by "prototypical". 30" radius in HO is a bit tight for the prototype engine but you have to make tolerances for the fact that you can't do the curves that the proto had. Build a section of 30" radius and see if you think that the engine fits on the curve to your mind. It will be better than asking everybody about what they think as everybody will have a different idea of what is right.
-- Bob May Losing weight is easy! If you ever want to lose weight, eat and drink less. Works every time it is tried!
Reply to
Bob May
"Keith Norgrove" wrote in message
Because my layout has 22" radius curves!
Frank
Reply to
Digital Railroader LLC
Why would it be better? I had a lot of helpful responses on my Big Boy. I wonder why some people here try to stifle conversation? If you don't have anything helpful to offer - just don't say anything at all, and I'll be perfectly happy to not have to explain why ask questions!!!
Frank
Reply to
Digital Railroader LLC
Well, all you need is a yard of flextrack.
In my view you would needto be around 4 ft radius before it starts to look good, but you can always put the tight bends in tunnel or behind viewblocks. Keith
Make friends in the hobby. Visit Garratt photos for the big steam lovers.
Reply to
Keith Norgrove
Frank In HO standard gauge hardly anything is going to look prototypical on a radius that is practical to use for most layouts As far as looking good I can't imagine a P2K 2-8-8-2 ever looking bad. There are some things that can be done to at least help trains of any size look better on curves. Curves that are eased and super elevated go a long way to make things visually and operationally better. The smaller the radius the more it will help. Especially for rolling stock over 40', steam locomotives larger than 4-6-0s or 2-8-0's, and any diesel the size of something like a GP7 or larger. I don't know how far along you are with your layout but in addition to easements and super elevation if it is possible to arrange your tightest radius curves that can be seen so they are viewed from the inside of the curve it will help, or at least I think so. Bruce
Reply to
Bruce Favinger
Frank, 22" may be a bit tight and although the swing from both engines may be apparent due to your smaller curves it may be the swing from the cab end that will catch you out. You'll just have to check this out to see if the cab fouls the footplate on the tender or as I found in one instance that the cab handrails were fouling the tender and causing a derailment and I have 40" curves. It'll just be a matter of experimentation to see if you have any problems or if it is visually acceptable and you can live with overhang. I would, if in your shoes, find a way to make it work as these are a beautiful engine and one of Proto's best models.
Regards Charles Emerson Bellbird, NSW, Australia
Reply to
Charles emerson
BY prototypical do you want some overhang or no overhang, since it seemed that it would take a rather large curve--36"--or more for no overhang, whereas if some overhang is acceptable, 24 is ok. I have some overhang on mine, but I run 24 inch curves due to room. Also I have found out that it does take some trial & effort to see if what I want to do on my layout will work. I wanted 30" curves but it was such a pain in the butt and it took too much room, and a whole lot of estimating and track workwork , so I settled on 24" atlas curves, which is acceptable to me to run an Allegheny, a Big Boy & a Challenger. Hope this helpd. jaijef
Reply to
JaiJEF
The question is at which point you are going to be satisfied with the appearance of the loco. For one answer, I'd not be satisfied with the appearance of the loco until you are running it on at least 12' radius curves. Others may be happy with 24" radius curves and that is a big difference in curvature! Thus it becomes a decision as to where you are happy. Besides, you asked for an opinion and I gave mine!
-- Bob May Losing weight is easy! If you ever want to lose weight, eat and drink less. Works every time it is tried!
Reply to
Bob May
That's still getting close to the prototype's minimum curvature. It would be severely speed restricted at those numbers. Probably not allowed to go more than 30 MPH (48 KPH) if that.
Captain Handbrake
Reply to
Captain Handbrake
Well, it's better than my 18" radius!
There will be overhang, most likely. The real question is whether that overhang is too much for you. My 2-8-8-2 looks semi-OK on my 18"R, the Rivo Challenger looks better, but the Rivo Cab Forward is really bad, period.
Of course, none of them look prototypical, but in my own eyes, it's a matter of degree. The Cab-Forward is ridiculous, while the Challenger is OK.
Kennedy
Reply to
Kennedy (no longer not on The Haggis!)
I can't speak specifically for the Proto 2-8-8-2 but I know the Rivarossi 2-6-6-6 looks fairly awesome going around 28" radius curves because my "local" hobby shop (Drybridge Station in Mt Airy, NC) ran one for a customer (who subsequently bought it) and it had almost no overhang. I would think your Big Boy would have looked good on 30" curves too.
Reply to
Bob
And with a 6-axle truck on the end, I'm surprised it didn't need a much larger radius to avoid overhang! Thanks! BTW, the Big Boy has been sold, but I still have the Proto 2000.
Frank
Reply to
Digital Railroader LLC
Regardless of how it looks, what is the smallest radius one of those large engines will navigate without throwing parts off the track into the laundry room? I have a 10 by ten space and need all the straight track I can put down, so I intend to bury the curves out of sight and of smallest radius.....
Jim Stewart
Reply to
Jim Stewart
LifeLike 2-8-8-2 no dimensions stated :(
Lionel 4-6-6-4 Challenger Minimum radius: 18? curves, 22? curves recommended
Broadway Limited 4-8-8-2, AC-4 Cab Forward Can be operated on minimum 20" radius curves. 22" Radius recommended for best results
So given those numbers, I'm guessing you could get away with 20" radius for your HO scale 2-8-8-2. With a reasonable edge margin that leaves six feet of straightaway on your ten foot table.
Reply to
Corelane
I don't have much more space, right now, and I'm wondering what the minimum radius you're considering that will not be in sight? (I have considered trying to allocate basement space outside of my train room, to hide my 22" returns, but the wife is reluctant to give up any more room! (grin)
Frank
Reply to
Digital Railroader LLC
That only takes into acccount operation - I'm also trying to consider how it will look going around those tight curves, and if it will derail cars it's pulling due to overhang...
Frank Eva
formatting link

Reply to
Digital Railroader LLC
I think I will try to do the tangent thing and narrow down to about 20" for the smallest radius. I have four tracks at the station, two are next to each other. These converge to three in both directions after the curves. the three go down to two for the far leg.... This will largely be a passenger layout representing Pennsy with catenaries wires and GG1s and 85 and 60 foot cars. Also, a gas-electric for running from that level down to an industrial level. Steel mill, Arc furnace, foundry, other heavy industry like Newark or other towns east of New Brunswick. Certainly some flat "Jersey Meadows" (salt water swamp). Passenger trains on high fill. Tunnel to tunnel is protypical. Some place a wider radius for through stuff and for supplying the heavy industries. Troop train, election campaign train (Dewey or Roosevelt) a few Bowser L1, K4, H9, etc. small engines. Maybe one or two big engines such as the 2 8 8 2 for through freight. (coal or reefers for NYC) no onlayout freight yards, no engine storage or repair facilities. GG1's will have a transfer table if I can figure out how to supply realistic looking overhead power. If I can get to a third level. (how do you nail quietly) I will have a coke plant and mine on a short side road on a high mountain. Visitors will look over the mountain toward the station and the city. two sidings there, one for commisary and USPS the other for REA. CTC signaled in both directions but not DCC in the near future. I am looking to have a number of trains run automatically for a future club layout.
Designed like toy trains with the scenery taking away the toyness. Most of the cith will be along the station wall with the station being a walkdown. Oh, I have already built a power substation and boiler plant with boiler for electricity supplying the trains and city....Have 2 Bachmann skyscrapers and an assortment of 3-4 story buildings. Skyline is a clouds wallpaper installed to draw the eye down. backdrop, modular section, and narrow buildings will line the walls.
Jim Stewart
Reply to
Jim Stewart
...snip...
This sounds like you will be running three parallel curves, and even though the 2-8-8-2 in question has both engines articulated so that it will run around a sharp curve, there will still be a heck of an overhang. You will need at least 2-1/2in centre-to-centre track spacing, which means the middle track will be 22.5in radius, and the outer track will be 25in. If your turnout arrangement permits, I'd keep the 2-8-8-2 to that outer track, since I suspect that anything much smaller than that will result in unreliable running. You might even find it worthwhile to add a couple oif crossovers in strategic places. In that case, you could go with 2-1/14in track spacing on the inner two tracks, which gives 25in + 22.5 + 20.25in radii. A 24in outer radius would give you 21.5in and 19.25in for the two inner tracks - not bad, I think, and gives you an extr inch of clearance for scenery and line side structures, which IMO is very important.
This sort of restriction for large locomotives and rolling stock was and is quite prototypical, BTW, and would make for some interesting operation, as some trains will have to switch from track to track in order to accommoadte the big engine.
You could experiment with some flextrack spiked to a piece of plywood, of course. Might be worth the exra time and effort, just to be sure, especially if you are running scale length passenger cars - they have quite an overhang in the centre towards the inside of the curve, y'know. :-)
HTH&GL
Reply to
Wolf Kirchmeir

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.