ProtoCAM: Additive Manufacturing, 3D Printing and Rapid Prototyping.

Metal Prototyping

Two additive manufacturing techniques allow service bureaus to produce metal parts and prototypes: metal casting, and direct metal laser sintering (DMLS). Each has its own best use case, and can deliver a wide variety of results to meet every need when it comes to speed, durability, aesthetics and budget.

Our Metal Prototyping Work

About Metal Castings

Metal casting techniques at ProtoCAM include investment casting, sand casting and plaster mold casting; they are far faster than conventional tooling and machining methods. This process is ideal for the rapid creation of short-run metal parts with a high degree of accuracy, durability and quality.

Investment casting, also called “lost wax casting,” uses a 3D printed wax pattern, a cast wax pattern, or an SLA QuickCast pattern. Parts can be created from steel, Everdur (bronze mix), aluminum and ferrous and non-ferrous metals.

The investment casting technique is excellent for:

  • Fast creation of multiple metal parts without the expense of conventional tooling.
  • Low-quantity (1-50) requirements.
  • Rapid prototype turnaround, with metal parts being created in 2-4 weeks or less, depending on method and foundry capacity.
  • Highly accurate, high-quality projects. Parts require little post-casting machining and processing to remove flashing and surface preparation, and ProtoCAM’s proprietary investment casting methods allow for walls as thin as .012 inches.

Sand casting, also called sand molded casting, is a metal casting process that uses sand as the tooling material. Mold sands that are used in sand casting include silica sand, olivine sand, chromite sand, zircon sand and chamotte sand.

The sand casting technique is excellent for:

  • Smaller-budget projects. Sand casting is the least expensive way to create short-run metal cast prototypes and products.
  • Rapid prototype turnaround, with metal parts being created in 2-4 weeks or less, depending on foundry capacity.

Plaster mold casting is extremely similar to sand casting. The key difference is that the molding material is plaster of paris, rather than sand.

The plaster mold casting technique is excellent for:

  • Projects that require a higher level of surface finish and accuracy than sand casting can achieve.
  • Rapid prototype turnaround, with metal parts being created in 2-4 weeks or less, depending on foundry capacity.


About DMLS

Direct metal laser sintering (DMLS) is an ideal rapid prototyping solution for customers that need high-quality 3D metal parts or metal prototypes quickly. Although DMLS typically costs more than other rapid prototyping techniques, no special tooling is required, allowing for turnaround times of two to four weeks. Typically used for highly complex, intricate parts that would be difficult or impossible to produce with traditional methods.

In direct metal laser sintering (DMLS), 3D metal parts are created by fusing (“sintering”) powdered metals with the heat from an infrared laser beam. Similar to SLS, these metal layers are repeatedly laser sintered, creating the desired three-dimensional piece based on a 3D CAD model or .stl file. Unlike SLS, there are multiple metal materials available for DMLS including aluminum, cobalt chrome, maraging steel, nickel alloy 625, nickel alloy 718, stainless steel and titanium.

Watch a video of DMLS:

Advantages of DMLS metal 3D printing:

  • DMLS metal 3D printing uses homogenous materials, minimizing potential complications.
  • Parts produced using DMLS metal 3D printing can easily be machined, EDM processed, polished, etched, textured and more.
  • Parts can be produced using a variety of material types.

Limitations of DMLS metal 3D printing:

  • DMLS metal 3D printing typically costs much more than other rapid metal prototyping techniques.
  • Lead times for quotes and part delivery are frequently higher than other technologies.
  • Depending on part geometry, DMLS metal 3D printing presents size limitations.

Typical Metal Use Cases

Small-batch manufacturing Simulated investment cast parts Temperature-resistant pieces
Machinable parts Functional prototypes