What is plastazote?
Plastazote is yet another type of foam. I first came into contact with it whilst on the the Artyfakes training course in 2015. A great thing about plastazote is that it comes in a huge varieties of not only densities but also thicknesses. The most common ones used for props is LD45. This is also a LARP approved density. On this blog post, I’m not going to go into details about what plastazote is but instead will be completely focused on my experiences of this material.
Where do I get it from? Not sure about other countries but in the UK, the best place I've come across is Poly-Props but they only do 1 density (LD45). Thames Valley Suppliessells it in different densities but it costs more.
- - Ranges from 3mm to thicc
- - Large variety of densities
- - Contracts with heat
- - Expensive
- - Not the easiest to sand but easy enough
- - Rougher surface than EVA
Working with plastazote
Whereas thicc thighs save lives, thick foam just costs a lot of money. Unless you're making something huge, it's probably cheaper if you bought one sheet and layered it instead. Yes, one could obtain thicker foam meaning you could save time and effort by not having to glue several layers together.
LD45 is extremely easy to work with because the low density means less effort to cut and the blade stays sharper for longer.Although this foam is as dense as the craft foam, plastazote feels easier to carve large chunks without the blade getting stuck or caught. Be careful when you are cutting the foam. If you cut too much and then heat the foam, the mistakes will stand out a lot since plastazote contracts when heated.
As always, try not to saw the foam. If you leave saw marks on curves, it'll be more time consuming to sand clean. Just slow down a little and get the whole cut done with a super sharp blade and one cut.
Both the gem and the spear were carved out of 12 mm. I was able to glide the blade through with very little effort. You might have spotted some lines right in the middle of the gem that look like they don't belong. That's because I accidentally cut into the foam a little too deeply. I corrected this by shaving a little more off. Imperfections can be shaved off or filled using foam clay.
Be careful when you sand.
Here I sanded the foam down by hand with 250 grit. As you can see, the foam became quite fluffy. Be careful when you sand because it is quite easy to rip the foam when you're sanding by hand. You could achieve a nicer finish with a smooth 120 grit sanding drum with a Dremel. Because of the density of LD45, apply barely any pressure when sanding because if you are not careful or you slip, you will very easily take a chunk out of your build.
Contracts with heat.
I blasted both sides with a heat gun evenly on low heat. On the left, you can see that the fluff from the sanding has disappeared but the surface is still fairly rough. On the right, I lightly scored the foam with a craft knife. Be careful when you are doing this because it took a little longer for these lines to appear. If you're not concentrating, there's a good chance your foam will end up like my pizza from last night.
Sealing with LatexThis was the first time I came across plastazote on the Artyfakes Training Course. Latex is a durable material usually used for LARP weapons. Since latex is thicker than other sealants, it smooths out the bumps quite quickly but be careful you don't lose your small details. We sealed the foam with about 5-7 layers of latex with a combination of brushing it on, dunking and spraying. The whole process was very time consuming and smelt like cat piss the entire duration. Caring for drips is also a pain.
Sealing with Hexflex/Seal/Plastidip
Whenever I seal my foam, I always use Hexflex as a base since it dries so quickly and seals the foam real good. The downside of that is that Hexflex is quite thin compared to stuff like Seal Prime or Plastidip. The reason why I use Hexflex first is because the latter products are much more expensive and Hexflex reduces the layers of Seal Prime/Plastidip since it prevents the first layers being soaked up by the foam. This was sealed with 3 layers of Hexflex and 2 layers of Seal Prime. As you can see, the holes are not fully covered. To get it smooth, I assume it would take 5 layers of Hexflex and 4-5 layers of Seal Prime.
Light defusing with plastazote
White LD45 plastazote is the best at letting light through. Be careful though. When marking out and gluing your foam, make sure you do a tidy job because that would save you a lot of effort trying to sand down glue marks. You still have to seal the foam but seal with with a clear sealer. Apply thin layers of paint to keep the foam translucent. The recommended method is to dust the paint on with an airbrush.
Kamui Cosplay ran through the process of how she made her Zinogre Dual Blades from end to end in a video. LittleJem has also created a demo video of her Xeno'jiiva Great Sword. It's worth giving these videos a watch.
As always companies labelling this foam with a completely different name then claiming they're the first to sell this "light defusing translucent foam" are pricks. Good marketing scheme because idiot cosplayers who don't process information for themselves are like the people who buy branded paracetamol.
To prove a point, look at the photos below. Ignoring the black dots on the foam because it's been living on my dusty floor for a while. This shows foam from 2 companies that are called different things. They both let the same amount of light through, has the same texture and feels like it is the same density.