In the sculpting and modeling world, clay falls in to two main categories; water based clays and oil-based clays. Because they’re both clays, you might be thinking they should do about the same thing but they are actually two totally different beasts and cater to two very different working styles.
The first thing you’ll notice when handling these two types of clay is consistency, or firmness. Water based clay is extremely soft and easily workable in your hands. This can be really advantages when working on larger works where you will need to build up greater quantities of clay. Working with a water-based clay can make it much faster and easier to realize a larger form. Oil based clay, on the other hand, is significantly firmer. Even the softest oil based clays can be difficult to manipulate at room temperature, which is great if you’re working on a smaller piece with a fair amount of fine detail, but can become a hindrance when working on a life or monumental scale.
Price is another area where these two clays differ. Water based clay, like Laguna’s WED clay (EM-217) will cost around $30 for a 50 lb. case. A similar quantity of oil based clay, like our 40 lb. case of Chavant’s NSP (Non Sulphurated Plasteline), can cost as much as $170. To put that into perspective, WED clay cost about $0.60 per pound of clay, compared to NSP, which costs a staggering $4.24 per pound. That’s a huge distinction in water based clay’s favor, but that’s where water based clays’ advantage ends.
Water based clays require a fair bit of maintenance. The clay will dry out and crack in just a few hours if it’s not kept moist, and once it’s dry it cannot be reused. While sculpting, you’ll need to regularly spray the clay with water to keep it from drying out. When the clay is not exposed to the air it has to be securely wrapped in plastic to prevent drying. In addition to the issues with keeping the clay moist, water based clays are also prone to developing mold. This is especially true during the hot summer months, and can make working with this type of clay difficult for people with severe allergies.
Oil based clays, on the other hand, can be reused almost limitlessly. The clay’s firmer consistency holds fine detail exceptionally well and because evaporation isn’t a concern, the clay is much lower maintenance. Oil based clays won’t develop mold, and can be left exposed to the elements for months at a time without drying or cracking.
If you’ve still got questions about how these clays stack up, let us know in the comments. If you’re interested in getting your hands on some clay samples, you can pick them up at afasupplies.com, completely free of charge.