It is a material that consumers have been craving for, direct measurement towards a product value. Yet, it is not friendly to manufacturers because turning the ZAMAK from its raw material shape (very much like a chocolate bar shape) into something specific requires very high level of casting and die design. the melting point of ZAMAK is over 400 degrees, it requires specific casting machine to carry out the work. As you can imagine, operators do not enjoy working with these machines because its surrounding environment incurs high temperatures.
When ZAMAK parts are formed straight out from the die-casting machine, the edges of the parts always connect with some residual materials. These materials were only useful during the process, called filtering bags to improve purity on the parts surface. However, removal of these residual materials, technically speaking, the polish process is tedious and requires a lot of attention from polishing workers, if anything goes wrong the parts would be total lost.
Despite the complicate manufacturing process of a ZAMAK parts, After all, it’s a human nature that we love metal, its weight, our sensation towards the metal surface, its high impact strength and ductility have forged the concept of “the more metal the better” in our mind.
CNC machined aluminum
Upon releasing between the cavity and core side of zinc alloy mould, any casting parts would inherit a parting line on its surface. This parting line is inevitable, even deploying the most sophisticated machinery during the tooling process could not guarantee a complete smooth surface, in most cases, a very tiny hair size parting line would still be visible to naked eyes. As mentioned previously, zinc alloy casting part would require polishing to remove flashes (substances spilled out from the mould contact surface due to high pressures). During the polishing process, however while attempting to remove flashes around the parting line, it could easily cause unexpected damages, in worst case the round surface would be distorted.
To achieve a more authentic gun barrel surface smoothness, Waltersons bought aluminium tubes with larger diameter and using precisely lathe machine driven by Computer Numerical Control programming system, known as CNC slowly trim down the tube diameter into desire size, even though this technique incurred a higher manufacturing cost compare to traditional casting, the extra effort would be highly appreciated by collectors in the end.