# Hollow core doors, good idea or not?



## spacomp92653 (Jul 5, 2018)

I'm trying to plan out a simple, new N scale layout, my first real model RR work in 40 years. I want to keep it simple, but use good quality track, turnouts, controls, locos, etc.

I've see a few layouts done on a 24x80" hollow core door, no doubt for cost reasons, simplicity, light weight, etc. Are there any negatives to consider?

My other idea is 3/4" birch plywood on 1x4" frame. 24x96"

Are doors stable or do they warp with time?


----------



## BrokeCurmudgeon (Feb 8, 2016)

I had very good luck with a 80x36 door.


----------



## prrfan (Dec 19, 2014)

I’ve been using doors for about 5 years now. Mine have not warped but I would not say they never will. Humidity plays a factor in this as well as how much weight is on them. This is usually negligible on most basic layouts. 

The upside is that they are light and maneuverable. They make a good modular benchwork and don’t need to have a supporting frame under them. I just support mine in the corners. You could even put them on sawhorses. 
The downside is the thickness. It’s a bit trickier running wiring through them compared to plywood. You also only have a narrow band of solid wood around the perimeter for fasteners. 
I used them because I knew I’d be moving a couple times and had to adapt to different locations. Overall I think the traditional plywood/foam or just foam is probably better in the long run.


----------



## mesenteria (Oct 29, 2015)

I don't know that there's anything inherently 'wrong' about using almost anything that is light, rigid, and easily transportable, especially in N Scale. Some HO people repurpose ping-pong tables. 

1/2 inch six-ply plywood will suffice for a stand-alone layout, but it will wobble a wee bit. It's also still heavy, although the 3/4" you are talking about will be very heavy. Very.

You can get 1/4" cabinet grade and tack it to a shallow box with a couple of joists spaced about 16" apart and be assured of rigidity and integrity. Form the box frame out of 1X4's.

Or, get 1/4" construction grade plywood and glue a 1" thick sheet of Dow Extruded Insulation Foam Board onto it. The plywood protects the nether side, and you get to build on the top side of the foam. I would fashion a thin plywood fascia around the edges of the foam to protect that as well.


----------



## CTValleyRR (Jul 26, 2014)

Hollow core doors are definitely a viable option.


----------



## J.Albert1949 (Feb 3, 2018)

My suggestion:

Use 1x3 for your framework.
Use 1/4" birch plywood for the surface.

The birch plywood is much better than "the regular stuff". More stable.
With cross-braces every 16-24", it will serve well (unless you intend to walk on it!).


----------



## spacomp92653 (Jul 5, 2018)

Broke..... very nice job on your layout, gives me inspiration :thumbsup::thumbsup::thumbsup:

thanks much for the advice. I do see the modular club guys all use 1x4" construction, just not sure what they use for top material, maybe foam.

I made a small 42 x 60 top for my wife's Christmas village and used cabinet grade plywood, 12mm thick, nice and flat, and painted one side. It is supported by a table 41x59" and it has warped; warped almost immediately after applying paint to one side only, it became convex on the painted side. So I'm learning, a frame can be important. And, maybe paint both sides.


----------



## traction fan (Oct 5, 2014)

*Hollow core doors and warp fighting measures.*



spacomp92653 said:


> Broke..... very nice job on your layout, gives me inspiration :thumbsup::thumbsup::thumbsup:
> 
> thanks much for the advice. I do see the modular club guys all use 1x4" construction, just not sure what they use for top material, maybe foam.
> 
> I made a small 42 x 60 top for my wife's Christmas village and used cabinet grade plywood, 12mm thick, nice and flat, and painted one side. It is supported by a table 41x59" and it has warped; warped almost immediately after applying paint to one side only, it became convex on the painted side. So I'm learning, a frame can be important. And, maybe paint both sides.


spacomp;

I have built two N-scale layouts on hollow-core doors. I used the 80" x 36" size, but there's no reason a narrower size wouldn't work, if you're short on space. It's true that only the outside 2" or so have any wood on the inside. The rest of the door's innards are usually shaped cardboard, and a lot of air. If you want to have wiring under a hollow core door train layout, just drill clear through both sides of the door, and thread the wires through the holes. A piece of stiff steel music wire can be used like a needle, to poke through the holes with your electric wire taped to it.
You can screw and glue a pair of 1" x 3" planks across the width of the door to attach legs. Just locate the screws at the edges, so they have some wood to bite into. For that matter, you could attach a frame under the door in the same way. Of course, if you build a frame, you won't really need the door. You could still use a door, or plywood, or extruded foam.

It's also possible to combine the last two materials, and build a very strong, rigid, and still very lightweight, structure.
I built the supporting arches of my "bookshelf" model railroad (see photo 1 ) in the same way as the "Lightwood" 2x2 (shown in photo 2)
It's made of 1/4" thick luan plywood, glued around a foam core, to make a box girder. I used waterproof yellow carpenter's glue, which forms a bond stronger than the wood itself. The finished box girder 2x2 is considerably stronger, and lighter, that the conventional pine 2x2 on the left in photo. The arches are so strong that they support my considerable collection of train books, a TV set, a VCR, and loads of other stuff, plus the railroad itself. 

Two things that help prevent warping are 'L'-girder construction, and painting, or sealing, all the wood. An 'L'-girder can be made by screwing and gluing a 1x3 and a 1x2 to each other to form a wooden version of a piece of angle iron. (see photos 3, 4, & 5) This structure is virtually impossible to bend. If you applied a whole lot of force, you could break it, but it wouldn't bend.
Warping is a form of bending that happens when moisture gets inside wood. Painting, or sealing, keeps the moisture from getting into the wood, and the 'L' shape keeps it from bending. 

Traction Fan :smilie_daumenpos:


----------



## WMnut (Oct 23, 2019)

I used 2- 80" X 36" hollow core doors for a O scale layout, light weight, but strong i can lean on them no problem, easy to fasten buildings, lamp post, track anything you want to fasten down.
Wiring is no problem, drill a small hole for wires, make the hole larger on the underneath side, wire drops right through, works great for me..


----------



## 65446 (Sep 22, 2018)

My only suggestion is to move the fire station to between the 2 houses, or rearrange it to have F. Sta. on right end. Then continue the road across a small bridge over the narrowest part of stream. From there continue the road along the river toward the mountain. Have it cross the curved track (small grade crossing) and connect to the existing grade crossing..Otherwise the fire trucks, autos and houses are trapped.  M


----------



## Eilif (Nov 6, 2017)

I've not used hollow core doors for layouts, but I've got a set of 5 aprox 1'x6.5' closet door panels that I've used for years for wargaming by laying them over a set of 2x4's to enlarge the playing area on top of a table. They have only paint on one side and they are stored on a 3 season porch that sees 100 degree temperature differentials over the course of a year. 

When I pull them out and lay them down indoors they're still just about perfectly flat. If I were going to do an N layout I'd use a hollow core door with no reservations.


----------

