Reason
1. Crossed blade is not sharp and the two crossed blade is unequal-high.
2. Center point of drill and shank concentricity are not meet the criteria.
3. The machine is on the condition of wrong spindle run- out.
4. The board processing (artifact) is on the move.
5. Spindle rotation and cutter speed is not match.
6. The adaptor concentricity is low and other technical data are not up to standard.
Reason
1. The center point and the shank is misalignment, or the center point is not sharp.
2. The artifact is on the move during drilling.
3. Spindle rotation and tool feed speed is not match.
4. The adaptor concentricity is low and other technical data are not up to standard.
5. The spindle of boring machine is loose or damaged.
Reason:
1. The blade edge is not sharp, the drill bit should be replaced.
2. Spiral groove (chip groove) is congestion that will lead to chip removal poorly.
3. Artifact (material) is humidity over limit or the glue quality is not good ( especially the fiber board and plywood ).
4. The tool feed speed is not match with the material and the depth.
5. Choose the suitable drill bit type for processing materials.
