N Scale At what length of tunnel does a "Behind the Scenes" and "Lift-Off" scenery access become necessary? As an example, lets say I have a Shelf against multiple walls but want the scenery to include some tunnels of various lengths. For a "short" tunnel I would assume that access from the tunnel portals is enough. Once we get to "medium" length tunnels I assume that access via "Lift-Off" scenery to get inside the tunnel becomes a need. With "long" tunnels then "Lift-Off" scenery is likely unpractical and "Behind the Scenes" access is needed. Based on your experience, how "short" of a tunnel only needs access via the tunnel portals and what would be considered a "medium" /"long" length tunnels? :question:
If you can't get ahold of a car "stuck" in the tunnel then you need better access........which means a tunnel that's more than a car length plus the length of your fingers. N scale portals aren't big enough to reach into with any type of grabber or more than about 2 fingers. That leaves the "poke it with a stick" method if you don't have any access.......which tends to be hard on the cars involved. And usually the inside of the tunnel is bigger than the portal, so the cars tend to wedge against the back of the portal as you poke at them. I'm not sure there's any "rule" about how much access to have, but I guarantee where-ever you don't have it, you'll have a ten car pile up.
I do like the 1-2 car length idea as a Short Tunnel as I would think that one could clean and clear derailments from the portals but after that some sort of "Lift-Out" or "From Below" access would be needed... Other Views??? :question:
Whenever possible, I have tried to have access from beneath. I have never been that talented at building durable lift off scenery, so a nice sized hollow area has done well for me.
I've built several tunnels for my modules and layout over the years. I line them on the sides to be consistent with the tunnel opening, which for the UP, is the way they did/do it. I've built short ones and long, curved ones, and I've two parallel tunnels for my Taggarts LDE that are curved and about 15" long. I'm not planning on engineering any access to them, but I'm making sure that my trackwork is top-notch for their interiors. The first thing I'd do is make sure that you don't have any rail joiners inside your tunnels. Then, I'd paint and weather the rails, then ballast your track, making sure everything is socked down extra good. Test run trains through your tunnel after each step. After you're happy with your tunnel interior, you might consider putting a top over the liners on the sides. I always spray the interiors ultra flat black, except about 2 to 3 inches in from the portals, then that gets painted and old, dirty concrete color...I do this with an airbrush to blend it into the ultra flat black of the rest of the liner. I haven't ever had a major problem or a consistent minor problem with running trains through my tunnels, so access is not a major worry for me. I had one tunnel on my old Ntrak modules that took the blue line behind the skyboard and that tunnel was over eight feet long. I lined the tunnel only for about a foot on either end, and the "interior" of the majority of it was under my skyboard, and trains were visible from the backs of my two modules. But, I never had a derailment there. I'm sure the secret to problem-free tunnel running is making sure your trackwork is top-notch. Then, you don't have to worry about derailments, and if you line the tunnel with near-prototypical clearances, cars that may derail don't fall over, but just get pulled through. Cheerio! Bob Gilmore
I run a couple of weighted Masonite track cleaning cars over the mainlines all the time in various trains. That seems to do the trick. Cheerio! Bob Giklmore
I've used removable scenery in all my railroads.My latest has a completely covered double track main in back that's probably 20 feet long.MY last one had 3 long covered areas.Track stays cleaner in completely closed tunnels,the dust simply can't get in them.I'd never make a RR with bottom access to tunnels again,just an absolute headache.All three mountains in the pics have mains under them,even the coal mine is removable.The mountain next to the Hudson alongside the turntable is removable,alsnly the track next to the mine is permanent.The removable sections are all solid styrofoam..
Hello. I have tunnels only as boundary condition at edges for correct work of straigt-forward part of layout. These tunnels have a reverse loop, train storage and d-drive. If You form and departs a train into one direction(tunnel boundary), After some time, this train must return also from this direction (this tunnel boundary), and You must disband it, serve it, and assemble it again, and depart it again(example for passenger trains). They also have: Watching windows and ability to shove hands for some corrections or repair. You can see it when videotrain moves via it: [video=youtube;-xMlipTv9rw]https://www.youtube.com/watch?v=-xMlipTv9rw[/video] [video=youtube;r36VAMmwxYc]https://www.youtube.com/watch?v=r36VAMmwxYc[/video] There You can see watching windows: [video=youtube;Y3Xy6zsefCk]https://www.youtube.com/watch?v=Y3Xy6zsefCk[/video] These tunnels can be easily opened for track repair and cleanings. Tunnel tracks also have electrically working DCC rigid tunnel catenary for improve E-pickup for electrical locos: [video=youtube;Qf6iPB7PoW4]https://www.youtube.com/watch?v=Qf6iPB7PoW4[/video] For track cleaning (in aim to save often openings ) i recommend to use automatical cleaning train with Vacuumer, and turning Swab for all 3 rails (Tomix, Lux modellbau). -------- Vadim
Lou, Your removable sections look great! Do you have any tips or write-ups on how you hid them so well? Thanks, Michael
My prototype mainline had a lot of tunnels along the lower Columbia River so the new layout design has them incorporated. However most of them were short in length thus most of mine will be short and aligned so that I can access both portals easily and the length for most is not over 4 car lengths. Only one will unfortunately be at about two feet just due to a design feature. That one will be accessed from under the layout. A lift off section is not feasible simply because the upper level branchline tracks run on top or I would favor the liftout. All the tunnels can be cleaned by a bright boy on a stick and by use of a self propelled track cleaner including the two footer.
John - When you say 4 Car lengths, what does that physical represent in "~Inches" since car lengths can vary?
Since I am in the steam era the largest cars except for passenger are the 50 ft. boxcars. That is at 3.75 inches per car for the 50 footers, times 4 equals 15 inches for most tunnels.
I was thinking you were Steam Era so likely 40-50ft cars where as I am going to be more modern... Thanks!!!!!!!
Don't do- S bends on a grade in tunnels; duck-under pop-ups with 300 degree tunnels; multi-level tunnel roundabouts/ helix; build mountains without a man sized fist space around the tunnel tracks etc.
