PCB Tech - PCB proofing: FR4 board processing flow

1. Introduction of FR4 board processing products
The processed parts of fr4 insulation board are based on different uses, and the industry is generally called: fr4 Epoxy Glass Cloth, insulation board, epoxy board, epoxy resin board, brominated epoxy resin board, fr4, glass fiber board, fr4 Reinforcement board, FPC reinforcement board, flexible circuit board reinforcement board, fr4 epoxy resin board, flame retardant insulation board, fr4 laminated board, epoxy board, fr4 light board, fr4 fiberglass board, epoxy glass cloth board, Epoxy glass cloth laminate, circuit board drilling pad. Main technical characteristics and applications: stable electrical insulation performance, good flatness, lubricated appearance, no pits, thickness tolerance specifications, suitable for high-performance electronic insulation products, such as FPC reinforcement boards, PCB drilling pads, glass Fiber meson, potentiometer carbon film printed glass fiber board, fine star gear (wafer grinding), fine test plate, electrical (electrical) equipment insulation support spacer, insulation backing plate, transformer insulation plate, motor insulation, grinding gear, Electronic switch insulation board, etc.

NEMA is a data specification of the American Electrical Manufacturers Association rules. The corresponding IEC International Electrotechnical Commission's specification is EPGC202, and there is no complete corresponding specification in China. The closest domestic standard is 3240 epoxy laminated glass cloth board, and the corresponding IEC standard of 3240 is EPGC201, and there is only a difference in flame retardancy between EPGC201 and EPGC202. Therefore, it can be simply considered that fr4 is an improved product of 3240 with enhanced flame retardancy.
The exterior colors of fr4 insulation board are:
Yellow fr4 board, white fr4 board, black fr4 board, blue fr4 board, etc.
The fr4 board is the substrate used by the PCB, and it is a type of sheet material. According to different reinforcement materials, sheet materials are mainly classified into the following four types: fr4: glass cloth substrate, fr1, fr2, etc.: paper substrate, CEM series: composite substrate, special material substrate (ceramic, metal, etc.) fr4 is impregnated by special electronic cloth It is a laminated product made of epoxy phenolic resin and other materials through high temperature and high pressure hot pressing.
The characteristics of fr4 board insulation board: have higher mechanical and dielectric properties, better heat resistance and moisture resistance, and have good machining properties.
Uses of fr4 board insulation board processing parts: used as insulation structure parts in motors and electrical equipment, including various types of switches, FPC reinforced electrical insulation, carbon film printed circuit boards, computer drilling pads, mold fixtures, etc. (PCB test stand) And can be used in humid environment conditions and transformer oil.
FPC
2. Processing method of FR4 board processing parts
1. FR4 drilling
This is a common processing method in PCB circuit board factories. Whether it is PCB testing fixtures or PCB post-processing, they will go through "drilling". Larger PCB factories usually set up their own drilling rooms, which are usually comparable to fixtures. Intimate, and the work in the drilling room is not an easy job, but it is more comfortable than the picture. Usually the consumables and equipment used in the drilling room are special drilling rigs, drill nozzles, rubber particles, wooden backing plates, aluminum backing plates, etc., drill nozzles The loss and the wastage of the backing plate are huge, and many small companies usually make a fortune by supplying a drill bit and a milling cutter to a factory;
In addition, the common way of drilling is the new LED lampshade retaining insulator. As an energy-saving industry, LED has been hailed in recent years, and LED is composed of many small lamps. This feature makes the application of insulating plates broaden again., Generally, the processing method of LED-retained insulating parts is to drill holes and then gong a circle. The FR4 processing method is relatively simple and the market is huge, but the characteristics are that the level is not high and the profit is low;
2. FR4 computer gong
The computer gong is the name of Guangdong and Hong Kong. It is simple to say that it is CNC or numerical control, and it is also called a machining center. In fact, they all have a meaning. The function of the computer gong is very powerful. It is divided into plane and inclined plane ( Or called curved surface), the category of bevels is relatively small, and flat computer gongs are very common. Small processing parts such as insulating gaskets, insulating rods, and star wheels are all processed by computer gongs to process epoxy boards and computers. The most important feature of gongs is that they are sensitive, fast, and powerful. It is currently the best and most commonly used processing method;
3. FR4 slitting
This is the most common and most common processing method on the market. Ordinary stores have a cutting machine for cutting boards. This is usually rough, and the tolerance can be controlled within 5mm. It is scary to say, I I have seen many shops or companies in Dongguan that do epoxy board. Companies that have been doing it for more than 5 years are still using angle iron welding cutting boards. Dongguan is known as the manufacturing capital. It seems to be a trick. This method has no technical content, but sometimes it can be very profitable. For example, if the calculation is normal, one and a half will be divided into 8 pieces, which is a small waste, but those stores that sell boards have a method to cut one board. For 10 small sheets, if the quantity is large, the profit will be very considerable;
4. FR4 milling machine/lathe
The products processed by this processing method are usually products such as parts. Since milling machines and lathes are mostly used for processing hardware parts, the slow processing speed of ordinary milling machines and lathes is a major feature, so if If you rely exclusively on this kind of epoxy board processing method, the company’s life will be greatly reduced. However, for jigs, these two types of equipment are necessary. In other words, if processing thick epoxy boards, milling machines and Lathe is the best choice;
5. FR4 carving machine
The computer carving machine is composed of a computer, a carving machine controller and a carving machine host. Its working principle is: the design and layout are stopped by the special engraving software configured in the computer, and the information of the design and layout is automatically transmitted to the engraving machine controller by the computer, and the controller converts the information into a stepping motor capable of driving Or a signal with power from a servo motor (pulse train), which controls the main machine of the engraving machine to generate X, Y, and Z three-axis engraving and cutting tool path base paths. At the same time, the high-speed rotating engraving head on the engraving machine, through the cutting tool configured according to the FR4 processing material, stops cutting the processing data fixed on the worktable of the host, and can engrave various planes or flat relief graphics designed in the computer. Text, complete the automation of carving and polishing.