Multi-Level Track Height

What's the height of your tallest piece of rolling stock?  I went with six inches from the base of the track.  I'm using FasTrack and everything I have fits.

My layout is a double track main.  I have two areas where the track crosses over each other.  In both places I'm using bridges.  My height is six inches.  If I used a tunnel portal the rise would be up about eight inches which would make the grade to high.  I think I'm about 4% now.  My plan is to put the tunnels over the track on a single level.  The photo shows two MTH steel arch bridges with girder bridges attached on each end.  I carved out a couple bridge abutments using stacked 2" blue foam for each end and remover the support column in the center of the arch.  I test ran my Big Boy with out any issues.  The other bridge is something I made my self.  I found a piece of steel framing from a construction site and cut it to fit the other cross over.  It's 10" wide and 25" long with the long edges turned up 1 1/4" it looks like a plate girder bridge.  I thought about making a tunnel at the other crossover.  I could place the portals about five inches from the track and have the mountain carved out so the track would be close to the top of the tunnel.

If at all possible, don't have tracks directly over/under each other.  If you have to, do it for the shortest area possible with as much height difference as possible.  It would be great if you had as much as one foot difference so you could easily reach-in, see, work on and exchange/clean track.  Always remember, the first problem will be exactly where it is the hardest to reach or work on the track.

Even in my areas where I have four levels of track, I used different diameters of curves so that the tracks are NOT directly above/below the others.

If you are talking about decks...try to get at least a foot in between and make certain that it's not too deep--like 30 inches deep and one foot up.  Eventually, you won't be happy with that spacing/clearance.

6" is more than enough to clear any and all equipment, including autoracks and double stacks

I like to allow 8" top of rail to top of rail. which should give you good clearence.

I'm in agreement with Popsrr as I'm also doing 8 inches heights between levels top of rail to top of rail. Using 1/2 inch plywood, 1/2 thick inch black foam between the wood (for noise reduction) and the Fastrack on top of the foam it makes it probably about 6-1/4 inches clearance from the top of the rail to the bottom of the plywood on the next level. That is fine for clearance for trains. I glue the foam to the plywood ( both having them be cut 1/2 inch wider than the Fastrack on both sides of the track to make the track stable) and glue the Fastrack to the foam. No screws at all, huge drop in track noise by using foam glue.

the most challenging pieces to run are any engoines with pantographs and the Husky double stacks. Even if you dont have any now plan for it now just in case

Steve

Two levels, as Gary mentioned, 6 1/4" seems to be a working minimum.  Note that the house on the bluff has been built-up from the plywood deck to blend in the MTH tunnel portal pictured.   The elevation pictured required a lot of grade, 10' to 12' to bring the levels together (3.8% grade)

We went with 8in. We had tried 6in and had cars that hit.

The k-line tunnel portals were 8in and worked well for our club.

we had tried the MTH and were to low for some things like flat car with trailer.

the trailers were getting pulled off. 

Dave

You are correct. In RRTrack, the "elevation" would be the change in height from two consistent points, i'e "top of rail to top of rail". The software would not have anyway of knowing how thick your roadbed/sub-roadbed would be. So you would need to plan grades to cover not only the amount of "clearance" you want but also allow for the support structure for the top layer.

Mine is about 7" and I wish it were 8 or more.  If you will have any tunnels on the second level, allow more clearance so that the entrances look right, i.e. there is a reason for the tunnel instead of a bridge.

My layout has 10" between levels and it is a little too much.  I would suggest 7 or 8 inches would be better.  Also, what stock do you plan to purchase in the future?  I made my own tunnel portals and found out that I when I put a portal on a turn, my Husky Stacks would touch.  A little trimming took care of this.  

Also, space the inside of your tunnels wider than you think you will need.  Many of the new cars or engines may say O54 curves, however, to make the curve, these cars will extend way beyond the track on the curves.  Unless you plan to only put tunnels and  portals on straight pieces of track, curves will be more challenging.

A good example is the new auto carriers from Lionel. All of my track is O72, however, I put a tunnel in a couple years and the over hang is so great on these cars, the auto carriers will not go the tunnels.  

You may not be able plan for everything, however, think about some of your future ideas as well.  

I guess I am way off the subject here.

You could put in some dummy catenary at the start of the tunnel and all the way through which should push that pantograph down a bit to clear the portal.

I use Folgers Coffee canisters for most of my elevations. They're exactly 6 1/2" tall. add to that 2" styrofoam. 

I added a 2nd level over the holidays and went with 8"clearance.

Come to thing of it, I am using 3 types of track ... main level has a fig 8 with O27 and an oval with O36 FastTrack. The 2nd level is an oval using O31.