Foamboard vs cardboard for dioramas - which is easier?

Cardboard is going to frustrate you if you need straight, clean edges, because it tends to fray even if you use a ruler. Foamboard is more forgiving in that respect.

That said, it really depends on what you want to do. If your diorama is small and is only going to have light decorations (little paper cutouts, plastic plants, that kind of stuff), thick cardboard works perfectly fine and it's cheaper. It looks just as good painted. The problem comes when you start hanging weight on it: large figures, structures, glued-on accessories. That's where foamboard keeps its rigidity without warping or sagging.

Another advantage of foamboard is that you can carve it to make more complex shapes without it breaking on you, and contact cement or hot glue stick to it beautifully. With cardboard you have to be more careful because it can get saturated with glue. If it's your first diorama and you want something easy, foamboard saves you the stress. But if you're just looking for a basic support for a simple scene, cardboard does the job without complications.

If what you need is something quick and hassle-free, foamboard wins hands down, but there's a detail that changed my life: cardboard becomes way more manageable if you let it rest for a couple of hours after cutting it, because it releases the internal tension and doesn't warp as much afterward. Either way, if your diorama is going to have heavy or wet elements, just go with foamboard - cardboard simply isn't designed for that and you'll end up with a disaster on your hands.

I made a forest diorama not too long ago and honestly, I switched to foamboard after getting frustrated with cardboard on previous projects. The difference is in the details: with foamboard you cut with a craft knife and the line comes out perfect the first time, whereas with cardboard you have to make several passes and even then the edge crumbles. Plus, if you need to glue trees, figures, or whatever, foamboard holds up way better without warping. With cardboard, after a while and with the humidity in the air everything gets wavy.

That said, cardboard has its place. If your diorama is small, without much weight on it, and you only need smooth background walls, it works fine and it's cheaper. But if you want something that'll last, that looks neat, and where you're going to have things glued or hung, foamboard saves you a ton of time and headaches. It's worth spending those extra pesos.

Don't go for foamboard just because it's "easier" if your diorama needs delicate details or textures - that material looks really flat and artificial if you don't finish it properly. What nobody mentions is that foamboard soaks up glue like a sponge, so if you use white glue or something similar it'll end up sticky and warped at the joints. Cardstock has its downsides with the edges, sure, but if you work it carefully (sharp craft knife, multiple light passes instead of one heavy one) it gives you way more versatility for textures, natural folds, and realistic finishes.

With foamboard you save yourself frustration, but be careful: if you cut it wrong or apply too much pressure, the internal structure crumbles and then there's no way to fix it without it showing. Cardboard at least forgives mistakes more because you can repair tears with glue, even if it's messier to start with.

You'll feel the difference in how they make you feel during the process more than in the final result. Foamboard is definitely cleaner to work with - no annoying loose threads or crumbling edges, and if you mess up with the cutter you can recover the project quickly. But cartulina has its charm if you don't demand perfection: it's more affordable, way lighter if your diorama is big, and you can paint it without it warping as much as some people say.

My experience is that choosing depends on how much time you have and how much perfectionism you need. If it's for school and you want to finish without pulling your hair out, foamboard without a doubt. But if it's more of a hobby thing and you can work with cartulina at your own pace, honestly it works well and costs less. The secret is that with cartulina it really helps to let it rest for a bit before cutting - the difference is noticeable 👍

Don't get fooled into thinking that cardboard is just "harder" - foamboard has its own pitfalls that nobody mentions. Yeah, foamboard cuts clean, but if you press hard to get through it in one pass, the core crumbles and the edges come out porous. With quality cardboard (not the cheap stuff) and a sharp craft knife, your edges come out pretty neat if you do several light passes instead of one heavy one. The real difference is budget and time - foamboard is faster if you know how to handle it, but cardboard is cheaper and the visual result ends up being almost identical if you're not asking for extreme structural integrity.