3. The copper hole of the orifice turns up
Cause:
Due to the backflushing, the copper foil is drawn into the blanking gap of the concave and convex dies.
The bonding force between the copper foil and the substrate is poor. When the punch is pulled out from the hole of the printed board being punched, the copper foil is pulled up with the punch.
The punch edge of the punch has an inverted cone, which expands and deforms. When the punch is pulled out from the hole of the printed board, the copper foil is pulled up with the punch
Solution:
uses positive punching.
Replace the punch.
The gap between the punch and the discharge plate can not be large, and sliding fit should be used.
