Hi All,

As I'm looking at a substantial upper level to my proposed N Gauge layout, I've been giving some serious thought to how to construct the upper level and would therefore appreciate your thoughts and ideas.

My lower level will be the typical 18mm x 44mm timber 'ladder' covered with 6mm MDF (oh! and 6' x 2 1/2').

The upper level will be roughly 5' x 2' in size and probably made from the same 6mm MDF.

My question is basically will I need to use the same structure under the board or could I get away with maybe turning the timber through 90 degrees and having a wider but lower upper level? Or could I get away with unsupported 18mm plywood (for example)?

Obviously this will have a huge impact on the layout as it will greatly affect the gradients.

So please, what are your thoughts and ideally experiences with upper level boards?

Hamish - as you say, the "upper level" will have a huge effect on your planning - the trains have to access it - via gradients !!  Death to real trains let alone models !!!

Your idea for the "base" level is perfect - however, I would advise against this method for the top deck because of the timber "ladder" - the difference in height would be too great.

I'd make the following comments for your consideration:

1.  Could you make the bottom deck "open topped" so that "risers" could be screwed to the bottom ladder ?
2.   Why are you proposing to use MDF for the board tops ?  It's very, very hard and dust from cutting is dangerous.  Have you thought about chipboard or ply ?
3.  If you use thicker board for the top deck - as you say 18mm ply (but I'm not sure you'd need to be that thick - 12mm ought to do), you could fix the risers to the edge of the ply thus avoiding any kind of sub-structure below the top deck.  Ply will support itself over a much longer distance than both MDF and chipboard which are both quite brittle.
4.  It is important to leave enough space between the 2 decks to gain access to the trackwork underneath but then, the greater the difference, the longer the gradient needs to be - always a "trade-off"

What I've done (in "OO" gauge) is to make the "base" level 3.5 cm up from my "ladder" so that to get 1 track over the other, I drop 1 by 3.5 cm and raise the other by the same amount.  In half the normal linear run, I have my 7 cm clearance.

Hope all this makes sense to you !!  :?  :?   Above all, keep your gradients as gentle as possible !!!!  :wink:  :wink:

Petermac

Sound advice on the gradients, Hamish.
In OO gauge the minimum should be 1 in 36 to enable an engine and three carriages to climb it without slipping. Someone will probably say that they have used less, but that usually means adding extra weight to the loco etc.
Logically the same ratio of climb can be applied to the smaller scale, but I know a few N gauge modellers who won't go steeper than 1 in 45 for N.

On my layout, I've climbed up 3" over 108", but that still doesn't give enough clearance to have tracks running underneath. My track plan didn't call for tracks under anyway, so no problem.
I assume you'll need to raise you track by around 2" in N gauge, so you'll need around  80" of rising line.
At first glance, it would seem that a 6ft long baseboard is not long enough to make the rise in one straight line if you use a solid top, but no problem if you use at least two edges of the baseboard. I'll let some of the members with an N gauge layout comment further.

Hi All
the other option would be to build a helix, just a thought.