PCB Technical - The effect of pcb on cover plate and backing plate

With the development of high-end, functional, and special PCB technology, the technology of cover/backing board as a PCB drilling auxiliary material is gradually developing toward diversification, refinement, and functionality. The quality and variety of the cover/backing board play an important role in ensuring the PCB drilling quality, yield, production efficiency, drill life, and PCB reliability. So what is the relationship between the size of the PCB drilling hole size and the selection of the cover plate and the backing plate? The editor will explain below

PCB drilling hole size is selected for cover plate and backing plate

1. It can improve the accuracy! The board table is copper! There will be a little slip! And if the holes are many and dense, the needles are easy to break! It's like you hit the cement directly with a nail, and hit the bottom cement through the soft mud, and think about the effect for yourself. There is also a reduction in copper!

2. In order to improve the drilling accuracy and reduce the drilling burrs during PCB drilling, aluminum sheets will be placed on the copper clad plate to be drilled to play a role of heat dissipation and guidance. When drilling holes, a paper backing plate will be placed under the copper clad laminate to guide and protect the drill bit

3. For the smaller the aperture, the aluminum sheet and the backing plate should be used well to prevent the hole deviation and the broken needle

The main functions of the cover plate and the backing plate:

1. Protect the board surface (protect the copper foil surface of the copper clad laminate or the copper-plated conductive layer of the substrate) to prevent the pressure foot from crushing the board surface; 2. Fix the drill bit to reduce the bit swing and offset when drilling, so that the bit can be accurately positioned; Improve the accuracy of the hole position and prevent the drill bit from breaking; 3. Prevent burrs and peaks on the substrate; Reduce entrance burrs; 4. Assist the drill bit to dissipate heat; Reduce the temperature of the drill bit; 5. Assist in cleaning the drill needle groove; prevent greasy Dirty holes; reduce drill bit wear and broken drills.

The main functions of the cover plate and the backing plate:

1. Suppress the under-hair (reduce export burrs); 2. Protect the drilling machine table surface for drilling through the PCB board; prevent the export burrs on the bottom surface of the PCB board; 3. Reduce the temperature of the drill bit and reduce the wear of the drill bit; 4. Clean up the drilling dirt on the drill bit to a certain extent; 5. Play its positioning function to a certain extent and improve the drilling accuracy.

What is the relationship between the size of PCB drilling hole and the selection of cover plate and backing plate? You can see their main effects to get the result

Regarding the relationship between the size of the PCB drilling hole size and the selection of cover and backing plates, the editor will temporarily introduce here, I hope it will be helpful to you.