(AutoART)
Since the original text is now in chinese on their site, let's google translate:
Why AUTOArt uses real vents and through-holes in die-cast model car:
In an alloy model car body of the vehicle, to produce a wear holes, is one of the processing operations of a consuming human.
The molding process of the alloy model car, through the instant punch of the high pressure and high temperature alloy melting soup concocted from steel molds. Therefore, the only casting out a whole lot of body shape, can not be any small hole or gap at the top of the cast product. Only the use of plastic materials, and only in the steel mold stamping out with a small hole or gap in the moldings. However, subject to birth defects of the plastic components of the boutique model car collectors can not accept the model car to the all-plastic body. These plastic materials are generally used only for the production of front and rear bumper, or the interior components.

This than 18 the proportion of car model, before the rate guide air intake and bumper is the use of plastic, many penetrating holes, resulting in the effect of grid modeling on behalf of the production of plastic materials.
Penetrate the pores, such as the conductivity of the body above the air intake or exhaust ports, usually in front of the car, after the bumper above. Many fine zinc alloy model cars we see on the market, most use plastic to make the car's front and rear components, constitute a fine product. This is the most common, and easy to process the production of the road; position, unable to break through plastic; the body, while the remaining zinc alloy to die casting.

Must rely on staff one by cutting out zinc die-casting alloy body front panels, with the body even with the air conductivity mouth shape.
Encounter of the location of the vents in the body, many manufacturers simply simplistic, in the mouth of the pores of the body solid, coated with black paint from the top of the visual effects, creating the shape of penetration. However, the black paint does not like the real thing, only directly to belittle the quality of the model. To pay a high price for the quality model car collectors, this is unacceptable and compromise.

Cutting the front of the air conductivity perforation, need specialized carving machine.
Create perforation effect in zinc alloy body, these holes must use the engraving machine to process one by one. The zinc alloy is very hard workers, the use of machine-assisted processing must be carefully and a small a small solid parts to wear a mouth wide open. Holes appear, the workers also then under a fine-tuning process, and trimming the edge of the hole, one by one carefully polished. This indeed is a time-consuming, and expensive human processing aspects of the product and easily processing accidentally brought a high scrap rate. Many model manufacturers to adopt the attitude of escape to avoid the use of this processing method, because, after all, to take into account the increase in production costs and production time-consuming.


Alloy model car body Qunjiao into the wind, was cut by the machine to cut out, the workers use a small file to the finishing hole to ensure a smooth and shape the right hole location.
Ao Tuya has never compromise on the processing operation. Standard model car, an expensive high-quality boutique collection visible body inlet and exhaust ports, must have ripped through the real shape, rather than a simple black & Paint instead. Otherwise, the model car will be grossly distorted.

Then cited this example, the the Ao Tuya's than 18 percentage of "Porsche 959 sports car, the whole body, including the former, after the bumper, are cast zinc alloy. All the pores of the body, front and back of the grid modeling, engraving machine, cutting out manual processing.

Among the most challenging position, the guide hole open tail wheel in front of the fender air intake. The thickness of the materials in this site is close to 10 mm, use a small drill bit slowly through these hard zinc alloy, really want to burn off the long working hours, resulting in this process become the most expensive car production costs where! The other model manufacturers, simply coated with a small black dots in the guide above the air intake, avoid stained processes in this trouble.