Die-cast and Resin refers to the material used to manufacturer the body of your favourite models. Die-cast involves the casting of Zinc Alloy, whereas Resin involves the casting of Resin Composite.
Molten Zinc Alloy is poured into a mold to cast the spare parts of the model. Zinc Alloy is a mixture of Zinc, Aluminium and Copper, which gives the body strength. This strength allows for features such as opening doors, engines, trunks or other moving parts. Die-cast is the most traditional form of model manufacturing, first seen in the early 20th century. Die-casting is more suitable for mass production, as the strong Steel molds can repeatably withstand thousands of castings without wearing.
Allows for functional parts; such as opening doors, trunks or other moving parts.
The unit price is much cheaper than resin.
Stronger and heavier
The zinc alloy is prone to deterioration when in certain environments, which can lead to blistering, distortion and cracking.
Rarely produced in small quantities
Generally produced in bulk, meaning models replicated are more mainstream.
Resin is poured into molds to cast the parts. To prevent the resin sticking, the molds are made from soft silicone which is subject to wear, so can only withstand small quantities of casting. Hence, why resin models are more commonly produced in small limited quantities. The casted resin is often more detailed than it's die-cast counterpart, however isn't strong enough to feature opening parts, or working suspension.
Favoured by many collectors, due to their small limited production runs
Small quantities allow for wider variety of models or even one-offs.
No opening parts, as panels aren’t strong enough
Weaker and lighter