Step one in your metal-manufacturing project is deciding the process that will bring it into being. The two principal approaches are stamping and repetition fabrication. Which of the technologies to pick is a function of many factors, and the ultimate decision impacts just as many: the quality, the design, the speed at which it’s produced, and how much it costs prominent among them.
Here’s how it breaks down.
Metal stamping (or pressing) describes a range of manufacturing processes for making precision components with a machine or stamping press that punches, embosses, flanges, blanks, bends, and coins metal. Metal stamping can be performed as a single- or multiple-stage operation.
Pros
• Stamping is cost-effective in situations where medium- to high-volume production runs of complex products are called for because it works on coil stock instead of sheet steel. It also produces less scrap.
• It is accurate and efficient, particularly in cases using highly automated coil-fed presses and incorporating secondary operations within both the press and/or die.
• It is capable of performing complex and precise work, easily negotiating close tolerances. It can also achieve a level of repeatability not possible with fabrication techniques.
Cons
• Because of the outlay required to develop and manufacture initial tooling, stamping may prove ineffective for all but longer production runs. This imperative also calls for longer lead times, so projects need to be ordered well in advance.
• Once the expensive metal stamping tools have been produced, changes to the design become impossible to accommodate.
Metal fabrication, on the other hand, refers to the creation of metal components by cutting (via sawing, shearing, water jetting, milling, or lasering), folding (by striking, or by using press brakes or horizontal folders), drilling, tapping (with an automatic machine), and welding. This may be followed by a final assembly process that brings the individual parts together with welding, adhesives, riveting, threaded fasteners, or swaging of crimped seams.
Pros
• Metal fabrication offers more flexibility and agility in prototyping and subsequent in-production product-feature adjustments than stamping because design changes can be implemented rapidly.
• It is a precise process that can produce a wide range of metal components that can be customized to specific customer requirements, in part because of advances in multi-axis press brakes, programmable controls, and computerized back gauging.
• This manufacturing option features shorter lead times, from design to production, than metal stamping.
• With laser cutting and auto-feed saws, sheet materials can be cut to size by way of a variety of effective techniques.
• Automatic lathes and advances in palletized production feed systems and machine tooling mean surfaces are more exacting, and tight tolerances can more easily be negotiated.
Cons
• The per-piece cost of metal produced this way is higher because metal fabrications are typically more labour-intensive. Material costs can also be higher than with metal stampings.
• Metal fabrication generally can’t handle the production of complex or unusually shaped pieces, so a pressing and stamping die may be needed. Deep drawn parts also typically fall out of this method’s range.
• The production cycle for metal fabrication is slower than that for metal stamping and pressing.
Tackling a metal fabrication project requires careful consideration of its various pros, cons, and priorities. If neither option emerges as the obvious choice, there is the possibility of a hybrid process that celebrates the best characteristics of both.