Why flex vs. sectional track? I use nothing but flex track and commercial turnouts on my layout. The only sectional track I have used are only re-railers, which I have added in staging to hopefully keep trains on the rails as they enter and leave staging.
Rio Grande. The Action Road - Focus 1977-1983
I have a fairly short tunnel (about 5') on a curve and a grade.
Here's couple views of the down-grade to the tunnel...
...and a view of the lower portal...
Here's a view taken by creeping under the layout, then partially standing (the inside height is fairly limited)....
...there's a piece of black cardstock, just inside of each portal, curved and then stapled to the 3/4" plywood roadbed.
I've run all sorts of trains through this tunnel, including a 44 car train of open hoppers loaded with Black-Beauty sandblasting material (22lbs. worth), and have never had an in-tunnel derailment in the 35 years since the layout was built.
The in-tunnel view is a little difficult to discern, but if you look closely, you'll notice that both sides of the track have a 2" high strip of 1/8" Masonite, glued & screwed to the 3/4" plywood roadbed, which, if there were a derailment, none of the cars would be falling to the basement floor.
Wayne
I had an HO two level 11x15 layout from the mid '90s thru 2008, and it had a few long tunnels - that proved to be a problem (because I installed a hidden #6 turnout inside). As a result, this layout's replacement had zero tunnel work.
My advice to the OP is to use flex track, avoid sharp curves, don't use any hidden turnouts, and install a rerailer(s) where feasible.
Also, if you can, provide access via underneath or behind it if possible.
ENJOY !
Mobilman44
Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central
I used flex, figuring the less tracks joints, the better, plus I soldered and added jumpers to the sections, along with the usual feeders.
I never though about adding a rerailer.
All of the scenery above my hidden track areas is made to come up, for access.
So, since 2011, I had to do that twice.
Mike.
My You Tube
Pls put me down for flex track in a tunnel.
I used flex track but put a rerailer near the beginning of the tunnel on a straight part, before the flex track curves. I figured it couldn't hurt.
DonRicardo What do you think is best for track laid inside a tunnel, flex track or rerailer, or both?
What do you think is best for track laid inside a tunnel, flex track or rerailer, or both?
I'd go with both. I like having a rerailer near both ends and flex track in between. Of course what works best depends on the length of the tunnel and if it is straight or has curves or turnouts. A very short tunnel without any curves or turnouts shouldn't require a rerailer.
The tunnel section (n scale) is 15 inches long, and has a 17inch radius curve. I have the cork road bed down but no track yet. There will be an opening in the fascia, just in case, and no turnouts. Also the section of flex track entering and leaving the tunnel has about 9 inches of straight track, the curve being inside the tunnel.
My engines (GP-40s) are all four wheel trucks, and the longest cars are Atlas 60' passenger cars with four wheel trucks.
The lay out is 40"x88" open grid.
There is a flex track joint inside the tunnel that has been soldered on the bench so hopefully no kinks.
Yes, I did finish my subway tunnel walls and stations for video viewing. It was really only a short loop track with a passing track, but there were 7 turnouts down there, after adding acces tracks to the surface and a couple of storage sidings. Fortunately, the subway cars are all heavy and rock solid. They never derailed. I lost a trolley wheel once because it fell off, and finding the missing wheel was a long, drawn out process.
It takes an iron man to play with a toy iron horse.
I want my tunnels to look as real on the inside as the rest of the layout so it is ballasted flex for me. A ride-along with a video camera exposes an unfinished tunnel interior. Not on my layout.
I have one tunnel I am working on that will be too long to fish out derailed cars by hand, but derailments on my layout only happen when some idiot forgets to throw a turnout. There are no turnouts in my tunnels.
Brent
"All of the world's problems are the result of the difference between how we think and how the world works."
How long is the tunnel? Is it straight or curved? Do you have access to the interior in case of problems?
My philosophy is to get track work that's as close to foolproof as you can. Still, my tunnels can all be reached through removable lift-off sections. I don't use rerailer tracks. For me, the best situation for inside a tunnel is a single stretch of flex track, as straight as possible, because that eliminates any track joints that might cause derailments.
Be aware, though, that many derailments have their root causes some distance from the point where you notice the derailment.