1. The process principle of printed circuit board (PCB) resin plug hole grinding production involves first utilizing special plug hole ink to cure the plug hole, followed by polishing to remove excess ink above the copper surface. Subsequently, wet film production proceeds according to the standard process flow for non-plug hole boards. Resin plug holes are typically finalized after a single copper electroplating. The grinding production process sequence is as follows: grinding plate → plug hole → curing → grinding.
2. To ensure the quality of inner plug hole grinding and prevent irregularities stemming from improper grinding equipment and conditions, addressing hole depression, corner damage, plate expansion and contraction, grinding roughness, grinding amount, grinding cost, thin plate capability, and grinding wheel compatibility are crucial. These characteristics must be strictly controlled to enhance overall process yield. The equipment commonly employed in PCB plug hole grinding includes automatic pressure-regulating grinding machines.
3. Automatic pressure-regulating grinders utilize ceramic and non-woven grinding wheels. Generally, ceramic grinding wheels exhibit superior cutting ability and do not leave surface dents post-grinding, albeit at a higher cost and shorter service life. Non-woven grinding wheels also offer excellent cutting ability but are prone to leaving holes due to structural factors. Despite being cost-effective, their price is significantly lower than ceramic wheels. Thus, selecting the most suitable grinding wheel combination based on individual plug hole characteristics is advisable.
4. Regarding printed circuit board expansion and contraction control, employing four-axis grinding for testing is recommended. Rotating the inner layer board by 90° before four-axis grinding enables optimal control of grinding roughness and expansion/contraction. Additionally, this approach disperses damage to the plug hole, preventing concentration in a single direction.
2. To ensure the quality of inner plug hole grinding and prevent irregularities stemming from improper grinding equipment and conditions, addressing hole depression, corner damage, plate expansion and contraction, grinding roughness, grinding amount, grinding cost, thin plate capability, and grinding wheel compatibility are crucial. These characteristics must be strictly controlled to enhance overall process yield. The equipment commonly employed in PCB plug hole grinding includes automatic pressure-regulating grinding machines.
3. Automatic pressure-regulating grinders utilize ceramic and non-woven grinding wheels. Generally, ceramic grinding wheels exhibit superior cutting ability and do not leave surface dents post-grinding, albeit at a higher cost and shorter service life. Non-woven grinding wheels also offer excellent cutting ability but are prone to leaving holes due to structural factors. Despite being cost-effective, their price is significantly lower than ceramic wheels. Thus, selecting the most suitable grinding wheel combination based on individual plug hole characteristics is advisable.
4. Regarding printed circuit board expansion and contraction control, employing four-axis grinding for testing is recommended. Rotating the inner layer board by 90° before four-axis grinding enables optimal control of grinding roughness and expansion/contraction. Additionally, this approach disperses damage to the plug hole, preventing concentration in a single direction.
