"Large MDF scenic base" Topic

I want to create a 60cm x 80cm area of marsh and plan to use 3mm mdf. I will tryy and keep moisture to a minimum by using spray paint etc. Will this be too big an area and warp? Any thoughts? Better product?

I have been using 3mm mdf as bases for houses/buildings so I can add landscaping, trees, grass, etc. I've done up to 120mm x 90mm and so far no problem. I primed them with Army Painter spray prime first and then added all the scenics. No problem so far and I like the look.

I'd say that you will need to keep the modelling on a base that size down to a minimum to avoid warping. If large areas are painted at one time then the shrinkage forces of the paint film will be enough to distort the sheet.

Try dabbing on paint with a sponge – even fillers/textures can be added the same way and left to dry/set before new layers.

Before you add details(flock,Trees). You can paint the bottom side and place Weights(Bags of sand) to take the warp out.

Do you mean 60mm x 80mm or 600mm x 800mm? The latter is way too big at 3mm thickness, I would think, whereas the former would be fine.

The ineffable Mal, the Terrain tutor:

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Ochoin – fantastic… spotty dog!

Do a test piece… Mel's theory is OK, but nothing beats a test piece!

I used vinyl floor tiles, cut to size, for several years. However, the PVA and paint, would cause it to warp, after 6-12 months. It looked fine, initially, but it always warped, after 6 months.

I've been using MDF bases, up to 6"/15cm-square, for over two years. No issues with it, yet, and I paint PVA on it, then apply sand, for texture.

Take a couple of test pieces. Paint one on one side only, paint the other on both sides. Wait six months, and see if either one warps. Better yet, paint another pair with PVA: one side, for one; both sides, for the other. Wait the six months, and see what they look like.

I realize 6 months is a long time to wait, so alternatively, build some test pieces. Write their build dates on their bottoms. Check them every couple of months by setting them on a flat, hard top, table. After one year, you will know for certain. Cheers!