Scratchbuilt building help and suggestion needed

[Alcidas]

ah so former user did you mean that using paper pulp would be much better because there would be less tension involved? might try that, how do you pulp it?

[former user]

in hardware stores or with professional suppliers, You can buy a stuff called "Makulatur" in german, that is basically shredded paper with glue, it is mixed with water to the desired thickness, and usually used to undercoat walls before putting wallpapers on (egg cartons and similar packaging is made of it). If You mix it with plaster it gets very hard and stable.
alternatively You can use finely shredded paper from an office that does this, mixed with wallpaper glue. I sometimes use flatter portions of the cartonage wetted with water for instant moulding, for instance when I want the interior shape of something, a boat e.g.

the advantage is that it will not warp, but only shrink a bit and keep the intended shape.
fiberboard for bases is not a good idea, unless in small sizes
I understand MDF is a good option but others have given better advice on that matter

[Alcidas]

Do you think MDF would work for a very large base (1200mm x 1800mm)?

thanks for that makalatur tip by the way, i will see if we have any equivalent in england...

[former user]

this is not a base, it's a gaming table 
I suppose yes, however it might be a bit heavy to handle with all the stuff glued on top?
there are people around here who can give better advice cause they built something of that size.

But since You ask - I have done that size and it worked without warping, but I would advise smaller modules for better handling.
In my case it was an architectural model, so a bit different, but it could not be broken up into portions

[Alcidas]

yes i might want to cut the size down a little, maybe 4' by 4' instead (about 1200mm by 1200mm) - specially because that specific size does not seem to be carried by most suppliers i can find online - but the aim is to build a small settlement, so kind of like an architectural model...

did you use mdf for your architectural model? what thickness did you use?

[former user]

2cm, but that's too thick for tabletops

[Alcidas]

2cm, but that's too thick for tabletops

Probably weigh a ton as well!

What would you suggest? Maybe a 6mm thickness? or would that be too thin?

What about hardboard? Does that warp more easily than mdf?

[traveller]

4 or 6 mm plywood with 2-3 battens on the backside is a good option

[former user]

why not make it modular?

[Alcidas]

Thats a good suggestion actually!

Dont know though, somehow it feels less epic...

[former user]

have You thought about the fact that You might have to move it through doors? 

[6milPhil]

Probably weigh a ton as well!

What would you suggest? Maybe a 6mm thickness? or would that be too thin?

What about hardboard? Does that warp more easily than mdf?

I've stopped using all these materials for building bases in favour of the wooden cork-backed table place mats you can get. The warpage on them, if any, is the slightest I've ever enjoyed. You need to roughen up the top to give a good glueing surface, but that's easy enough.

Using papier mache is likely to always be troublesome though because of the amount of water involved.

[Alcidas]

have You thought about the fact that You might have to move it through doors? 

I have actually. Sideways and through the door. Although, since its more of a diorama than a gaming table, we will only be moving it around if we have to move house.

[Diceplague]

I only use fiberboard/hardboard to base small terrain. I´ve found that if the base is going to be larger than 5 square inches they tend to warp a little. Don´t worry nor give up, messing around is a part of the learning process. Maybe next time try to avoid too much water on the base.

[Christian]

Buy some cheap-ish clamps and hold the thing down to a table-top for a few days. Add something heavy for weight at strategic points. Usually forces any warping nonsense out of the base for me