plywood or mdf

Hello Gents, need a bit of advise

I intend to build several generic « boulevard elements » in 20mmm size approx 25x30cms.. with cobbelstome and lots of rubbles /furnitures etc..

I wonder whether you would recommand thin plywood or thin mdf for the bases, bearing in mind that i intend to glue foam and elements with wood glue (and i’m not sure the MDF will be happy with that…)

So ? what would you recommand?

thanks

Plywood is not immune to warping when one side is saturated, any more than MDF is. Both materials should be sealed before glues and paints are applied.

thanks for your answer.. How would you recommand this "sealing"? please

I use a spirit-based aerosol primer — Rustoleum — because it's quick and easy. But a brushable acrylic primer works fine too, as long as you do both sides at once so that moisture penetration is equivalent on both sides. The wood needs to be sealed on both sides and all edges to ensure that moisture stays out when you start gluing and painting.

Even so, if you're using a lot of glue or paint in your final landscaping, some warping is possible, as PVA (white glue) and acrylic paints both shrink as they cure. the sealer coat helps to minimize this, as the top glue/paint layers aren't actually attached to the fibres of the wood.

thanks, will defo have a go...

Also if you can get old stocks of MDF, this is much better. You can tell when you have the right stuff because it sparks when cut with a circular saw

Having come up with a useful new material, the building materials' industry then consistently spends an inordinate amount of effort to turn it into crap.

MDF, or medium density fibreboard, is way better material than regular plywood, specially if you intend to use thin board. If using normal ammounts of glue it won't Warp or shrink at all, you need to soak it fully before it changes shape but cource basecoating is a way to go with both materials. Downside of MDF is that dust it produses when sanded etc. is bad for your health, be sure to wear some protection.


One option could be foamcore, https://en.wikipedia.org/wiki/Foamcore , highly recommended.

Thin plasticard is not all that expensive and much less prone to warping, A4 sheets will be close enough size wise.