The situation that router breaks earlier than its usual tool life.
There are mostly two reasons why a router breaks. Deflected breakage is caused by the radial force,
the router bit is
normally broken at the end of the flute.
Twisted breakage is caused by the large torque, and the router bit is normally broken at the middle
of the flute.
Cause | Failure condition | Countermeasure |
---|---|---|
Top geometry of the router is not suitable for drilling. | Breakage occurs because thrust force is too big. | Make pre-holes at the starting point of the routing in advance. |
Reduce Z-axis feed rate. | ||
Breakage occurs at the moment when the router tip contact with the board. | Use a router with a drill point geometry on the top. | |
Poor router bit strength. | Large deflection causes break at the end of the flute to router bit. | Change router geometry (web thickness / flute depth, web taper). |
Long flute length. | If flute length is unnecessarily long, router bends and breaks easily. | Decide flute length suitable for the stack heights of PCB. |
Cause | Failure condition | Countermeasure |
---|---|---|
Low Z-axis feed rate (in the drilling). | Because swarf evacuation becomes worse or cutting edges are damaged, cutting force of the router increases and breakage occurs. | Reduce Z-axis feed rate. |
Fast feed rate (X, Y-axis, work table). | Too fast feed rate causes large cutting force of router. In this situation, router breaks easily. | Reduce feed rate (X, Y-axis, work table). |
Low spindle speed. | Too large chip load causes breakage. | Increase spindle speed. |
High spindle speed. | High spindle speed hastens the cutting edge wear, and the router breaks early. | Reduce spindle speed. |
High spindle speed causes slip of the router in the collet and breakage. | ||
Reduce spindle speed. If the grip force is weak, repair the spindle (collet). |
Cause | Failure condition | Countermeasure |
---|---|---|
Unsuitable stack preparation of boards. | The inadequate fixing of boards makes them loose. In this case, the router becomes unstable and breaks easily. | Fix the boards to the work table rigidly (check the stud pins and the fixing tape). |
Stack height of the boards is too high. | Too high stack height causes large cutting force of router. In this situation, router breaks easily. | Reduce stack height of the boards. |
Many copper layers, or thick copper layer. | Too many (or too thick) copper layers cause large cutting force of router. In this situation, router breaks easily. | Reduce stack height of the boards, or reduce feed rate. |
Hard material (glass cloth, resin) of boards. | Cutting edge is damaged heavily during the routing hard materials. In this situation, router breaks easily. | Reduce stack height of the boards, or reduce feed rate. |
Foreign objects on the board. | Router breaks after contact with the foreign objects such as tape to fix the boards, or chips of the board that are cut by the router. | Remove foreign objects, fix the tape on the outside of the routing course. |
Cause | Failure condition | Countermeasure |
---|---|---|
Large spindle runout. | Because the rotation of the router becomes unstable, router breaks easily. | Repair the spindle (collet). |
Weak grip force of spindle. | Router slip in the collet during the routing, finally the router comes out from the spindle. | Repair the spindle (collet). |
Dust in the spindle (collet). | Because of the dust, router slips in the collet and breaks. | Clean the spindle (collet). |
PRODUCT 01 PCB Drills / Routers / Ultra precision micro-hole drill