Layout Construction: Using Insulation Board

[Knight of the Thistle]

Hi There,

Looking for a little advice... I'm thinking of using some Insulation Board as the base for my layout; both for scenery and as an initial base for the track. I'm hoping that doing this will enable me to raise the trackbed up a little so that I can have an embankment and viaduct.

I have never used insulation board before but have heard people talk of Celotex; that is quite hard to source at the moment but my local Travis Perkins has both Recticel, Xtratherm (both of which look very similar to Celotex) and Kay-Metzeler board in stock:

https://www.travisperkins.co.uk/insulation-board/recticel-eurothane-general-purpose-insulation-board-2400mm-x-1200mm/p/9000196435
https://www.travisperkins.co.uk/insulation-board/xtratherm-pitched-roof-board-xtpr-2400mm-x-1200mm/p/9000197590
https://www.travisperkins.co.uk/insulation-board/kay-metzeler-eps70-expanded-polystyrene-insulation-board-2400mm-x-1200mm-x-100mm/p/277202

The Kay Metzeler seems more of the expanded polystyrene type similar to that produced by Woodland Scenics - my fear with this is that I'll get polystyrene balls everywhere so it's probably my third choice.

I wondered if anyone had any experience constructing a layout scenic base / track base using these?

Specifically, my concerns are:

- How easy is it to cut/carve?
- Will it warp? (The layout is in a spare room so no wild temperatures)
- Is it safe (Ie it's not full of asbestos or something similarly dangerous!)?
- Is it easy to fix down and attach other items to it (such as plaster etc)?

My layout is 11ft x 3ft, so I would think a single board will be sufficient, at least for the trackbed.

THanks in advance,

Matthew

[NTrain]

Club I was with used it for scenery. We placed it on  plywood base and carved with sharp blades, surform, then sandpaper.

We were covering over with plaster cloth, suitably soaked, then added scatter/paint etc.

[Chuffington]

For scenery such as hills I normally use pieces of expanded polystyrene and packaging chips and then cover with 2 or 3 layers of plaster cloth.
Cheap solvent-free grab adhesive such as Screwfix No-Nonsense comes in a standard cartridge for use in a sealant gun and works fine with expanded polystyrene without melting it.   

[The Q]

Both reticel and xtratherm look ok.
No asbestos is allowed in anything these days except for extremely limited purposes so you won't find it on general sale.


They are easy to cut using a sharp knife or saw, but it produces a lot of dust not directly toxic, but not good to breath in. So a simple corona Virus mask will do while cutting, particularly sawing and clearing up the dust.

Don't take the tin film off unless you have to,  removing just one side will give you a banana.

Frame the foam with ply,  I use 3 inch foam as the base board, framed in 5mm ply, wooden inserts in the corners to screw to, I use the screw fix "No nonsense" version of  "Sticks like Sh*t " type adhesive of the non solvent kind.

Then glue , more foam on top to cut into, leave layers of glued foam for some time (I leave it a week) as the foam stops it setting quickly.

If you want land below the track, set the track height above the base board on a layer of foam, that will be cut into.
I coat my scenic foam with  cloth soaked in a polyfilla / pva / water mix, it produces a nice hard "shell"

Servos / point motors you can cut, say a 4 inch square hole from beneath glue in a piece of ply  and mount them on that. or do as I perfer to use wire in tube to the back of the layout and mount them there, no crawling under layouts to work on the wiring.

[ntpntpntp]

I'm not a fan of using traditional insulation board for track bed, too soft and doesn't hold pins (if you're pinning track).  I gave up on it back in the 70s.   Since the 90s I have used 9mm ply as my standard material for board construction.

For scenery use whatever material is to hand.  I like expanded polystyrene, it's light, easy to cut and glues with PVA. Used with an open top frame layout the polystyrene fills the gaps nicely.  I would always recommend open frame style of construction if you want to achieve interesting scenery above and below track level.

[Bealman]

Same here. I tried insulation board for a 009 rabbit warren layout back in the seventies, and was not impressed with it.

9mm ply for anything to do with baseboards ever since.

[Dorsetmike]

I use Kingspan from Wickes (they used to do celotex) as it doesn't hold track pins I cover with cork tiles; with any of the foam products it is best to use a very sharp carving knife, that will avoid most of the granules produced when using any type of saw or bread knife.

[Knight of the Thistle]

Thanks all for your feedback on this - a mix of opinions for sure!

I have a plywood baseboard - purchased from one of the online manufacturers - that is a really good base. My woodworking skills are pretty poor, so I am leaning towards the insulation board option as that will provide me with a consistent height for my track; my concern would be that going the raised plywood trackbed with L-shaped supports route I wouldn't get a consistent height and I don't really have the tools (either literally or metaphorically) to make a good job of it that way.

I think I'm leaning towards buying a sheet of 100 or 150mm thick Recticel/Xtratherm and cutting it up using one of the specialist saws you can pick up for £15-20. The main priority for me is raising the trackbed and then having a consistently flat and stable trackbed.

[Dancess]

I use extruded polystrene as it's cheap here and is available in various thicknesses, fixed to a solid wood base with adhesive which is meant for polystyrene and comes in 1kg tubs for about 4€. You just need to decide on your datum level so scenery can go above or below track. It also cuts easily with a sharp Stanley type knife.

Here's a link to what is available here.

https://www.leroymerlin.fr/v3/search/search.do?keyword=polystyrene%20extrude

[ntpntpntp]

@Knight of the Thistle   I can understand your concern if you feel your woodworking abilities might not be up to creating an open frame style    The traditional fully flat topped "train set" baseboard is really good to get started but unfortunately very limiting for scenery if you want something other than an urban or industrial flat scene. 

The trouble is, if you're then going to place a thick layer of something else on top of the solid base, and then your trackwork on top of that, you're really going to make life hard for yourself with wiring, fitting point motors etc.  You really need open access underneath the track.

You could probably get some consistently cut wood blocks done, glue these to the baseboard on appropriate places to support some ply for the track bed. You're still making access difficult though unless those blocks create enough height to get a hand underneath easily.

[Knight of the Thistle]

Thanks @ntpntpntp - I am going to use Kato Unitrack for this layout so the wiring / point motor fitting is a little simpler - my plan is to simply drill holes right through the polystyrene and plywood and out through the base. I know this sounds like I'm short-cutting on both the baseboard construction and the electrics (and I am) but I my concern is that with a layout this size they will otherwise bog me down forever.

[jpendle]

Hi,

I also use Extruded Polystyrene (XPS) for my baseboards.  I don't bother with a wooden base I just use a conventional wooden baseboard frame and put the XPS on top of that.
I use the 1" thick variety and even a single layer is rigid enough to form the baseboard.
It's very easy to carve with a sharp, non-serrated blade.
On my layout the various sections have between 1 and 3 layers of XPS to provide the contours and levels that I need.

Regards,

John P