This article will elaborate different techniques on how to electroplate unto cores. Applications are manifold and especially interesting when conventional methods hit a technical or economical wall.
Basically, we distinguish between reusable and lost cores.

1.) Reusable Core: 1st type
2.) Lost Core: 2nd type

Reusable Cores
These are used if core and the resulting galvanic layer can be separated. It’s important that the material of the core and the galvanic layer’s expansion coefficients are different from each other.
The bigger the difference the easier the separation becomes. Very much suited for this are plexiglass, stainless steel, aluminum, and Invar (Nickel 36). Since the core never gets used up it can be reused infinitely.

Lost Cores
If a hollow body has a complex inner geometry, or if it is very sensitive, the use of lost cores comes into play. The most typical material for this is aluminum which can be etched out after the galvanic process. Wax and other meltable materials are possible, those often need to be tested on a prototype first.

Advantages of this manufacturing method

• Complex inner structures can be formed by creating a negative shape as a core
• Very thin-walled structures become possible (e.g., copper pipes with a wall thickness of 100 µm)
• Heat exposure of 0°C-100°C, depending on the demolding method and the chosen galvanic material
• Galvanic joining and flanging are done at room temperature, therefore, there’s neither heat exposure nor warping.