Everything can be used somehow… and this also applies to polystyrene. Use it to make a clear varnish that works as a primer, but also as a base varnish for wood.
Buying paint today is an investment. Especially if you need a larger quantity that will cost you several hundred crowns. That’s why there’s nothing better than making your own transparent, waterproof varnish that you can use on wood. All you need for this is polystyrene (Styrofoam). You don’t have to buy it, but just use the scraps you have left as fillings from the fragile packages.
A cocktail full of chemistry – BEWARE of acetone!
You will need acetone to make the varnish. It is a strong solvent that quickly dissolves polystyrene. But you should know that it is a dangerous, flammable substance (flash point -20 °C) that releases toxic fumes. That’s why it’s important that you work with it outside. Be careful when handling acetone and protect yourself with an FFP2/3 vapor respirator, hermetic safety glasses, and nitrile gloves. Otherwise, there is a risk of headaches, eye or skin irritation.
Possible extinguishing
If you are a smoker, forget your cigarette when working with acetone. In case of ignition (which can also happen) NEVER put out the fire with water. Only with sand or foam.
Production of home varnish
If you have protective equipment, safe clothing (long pants and a long-sleeved sweater) and a place to create paint, prepare everything you need: 2 liter glass jars with a wide mouth and a cap, 2 smaller glass jars, 0.5 l acetone, a pile of polystyrene, a metal funnel (never use a plastic one!), new coffee filters.
Preparation procedure
Pour 1-1.5 cm of acetone into the first container (open!). Cut the styrofoam blocks into small pieces and add them gradually – the styrofoam will dissolve and the volume of the mixture will decrease. Allow to infuse uncovered overnight (never close – bubbles and pressure build up!) In the morning, filter the mixture through a metal funnel with a coffee filter into the second container. And you have varnish in the world!
Good advice
The resulting varnish attracts flies – the fumes kill them, so cover the container to prevent dirt from getting into the varnish. Experts recommend preparing the varnish with a thinner consistency – it is then better applied, for example with an old toothbrush. The varnish soaks into the wood beautifully and is almost impermeable to water.
