An advanced driver assistance systems (ADAS) camera only works if it knows exactly where it is looking. The assistance software interprets the image on the assumption that the camera holds a specific position and angle relative to the vehicle. Any deviation results in misjudged distances or misread lane markings, and that physical reference is not set by the camera, but by the housing that holds it.
That is why, in an ADAS housing, dimensional stability is not a desirable feature: it is the main function of the part. And in a zamak die-cast part, that stability depends on decisions made long before final inspection.
ADAS camera calibration: why the housing is the reference
The housing defines the support points for the optical module, the mounting surfaces for the bracket and, in many designs, the seat for the electronic board. If any of these dimensions varies between batches, the camera can be fitted correctly and still end up out of its reference position.
The challenge is not to make one part that meets its dimensional tolerances, but to make thousands of identical ones. Calibrating the system on the vehicle assembly line can absorb small variations, but the more repeatable the housing, the less the camera depends on that correction.
Properties of zamak that support dimensional stability
Zamak melts at considerably lower temperatures than aluminium. This allows it to be injected using the hot-chamber process and reduces the thermal stress on the mould in each cycle. A mould that degrades less holds its dimensions for longer, which means more consistent parts throughout series production.
Its fluidity in the molten state also allows thin walls and complex geometries to be filled faithfully. An ADAS housing combines reinforcing ribs, fastener seats and support surfaces, and zamak makes it possible to produce them in a single injection, with less subsequent machining than other processes. It is one of the advantages of zamak in precision parts that matters most for this type of component.
The mould in die casting: where repeatability begins
The precision of the housing is largely decided in the design of the mould. The position of the metal gates, the cooling system and the thermal balance between cavities determine how the part solidifies and, therefore, how it shrinks.
Uneven cooling can cause one area to shrink before another, leaving the housing slightly warped even though each individual dimension appears correct. That is why the preliminary engineering work with the customer focuses on identifying which surfaces are critical for the camera and designing the mould to protect precisely those areas.
Die casting and surface treatments: their effect on dimensional tolerances
In die casting, the aim is for the housing to leave the mould with its functional dimensions already within tolerance. But the part is not finished when it leaves the machine: what happens next also affects its final dimensions.
Surface treatment is also part of the dimensional calculation. An electrolytic coating adds thickness to the part, and in a precision seat that thickness must be allowed for from the design stage. Controlling its uniformity on internal areas and edges is as important as the corrosion protection it provides.
Added to this is the natural ageing of zamak: in the weeks following injection, the alloy undergoes small dimensional changes. In parts where the reference is critical, this should be factored into the tolerance design, or a stabilising heat treatment should be applied.
Dimensional tolerances: verifying what has been built
The final stage confirms that everything before it has worked. In an ADAS housing, inspection focuses on the functional dimensions, those that fix the position of the camera. Continuous monitoring of these dimensions makes it possible to detect process drift, such as progressive mould wear, before it affects a single delivered part.
At Jegan, we manufacture zamak brackets and housings for ADAS with the entire process integrated in-house: engineering, mould, injection, secondary operations, surface treatment and quality control. That integration is what allows us to treat dimensional stability as what it truly is in these parts: a requirement that runs through the whole of manufacturing.
About Jegan
Jegan is a company based in Deba (Gipuzkoa) specialising in zamak die casting and surface treatments, which we carry out at our plant in Eibar. We were founded in 1972, and in 1991 we became a Sociedad Anónima Laboral, an employee-owned company: those of us who work here are part of its ownership, because we see industry as a shared project.
This way of doing business rests on three commitments. On sustainability, we run on 100% renewable energy and between 2022 and 2025 we cut our emissions ratio per tonne of Zamak-5 by 86%. On equality, women make up 50% of our board and management team. And on local commitment, we keep our activity and our jobs in Gipuzkoa while exporting more than 90% of our production to European markets.
