Mercer Spring specializes in 3 types of spring design: compression, torsion, and extension, and also in the manufacture of custom wire forms. We also have the capability to make springs using square or rectangular wire. Our manufacturing process consists of utilizing either a mechanical or CNC computer driven coiler. Each coiler is specifically programed to control the length of wire needed, number of coils required, the correct inner and outer diameter, pitch, and spacing. Once these parameters are established and the prototype spring is tested to determine it has the correct free length, load, set, and other requirements, our coilers are set to fill your order. Once the springs are formed, they are oven heated to release the stress on the wire. They are then retested and either ground flat on the ends as is the requirement for many compression springs, or they may be fitted with loops or hooks as is the case with many extension springs. Finally, the springs or forms are tested again before packaging and shipping to ensure they meet all customer requirements. Blanket orders can be produced in bulk and released in smaller batches as required by each customer at specified agreed upon release dates.