Engraving and milling machine spindle is a kind of high speed, high rigidity and precision motor. It is supported by precision rolling bearing, lubricated by grease, cooled by external circulating water. Engraving (milling) spindle is generally used vertically. Whether the method is correct or not will directly affect the quality of engraving and milling and the working life of spindle.
1. Avoid impact
Strong impact, especially at the end of the main shaft and the front cover, is not allowed, otherwise the precision bearing and the accuracy of the main shaft will be damaged, resulting in the loss of the rotation accuracy of the main shaft.
2. Proper installation and clamping
Before installation, confirm that the spindle motor is in normal state, mainly referring to the appearance is not damaged and the spindle rotates evenly. Check with megger that the insulation resistance of stator to ground is above 200 м Ω. The fit tolerance between the outer diameter of the spindle motor sleeve and the clamping seat hole must ensure that the sleeve of the spindle motor can smoothly slide into the seat hole. Under no circumstances can hammer or other tools be used to position the spindle, and the clamping force should not be too large, otherwise the ball raceway of the precision bearing will be deformed, and the spindle accuracy and service life will be affected. After clamping, check that the runout of the centring surface of the taper hole at the front end of the main shaft shall not be greater than 0.003mm, and the rotation of the main shaft shall be light and even.
3. Installation of collet (ER type) pressing cap and cutter
The installation of the cutting tool must ensure the rotation accuracy, otherwise it will produce severe vibration, which will affect the carving (milling) quality and efficiency and bearing life.
The collet, pressing cap and tool as well as the taper hole at the front end of the main shaft must be wiped carefully. Excessive force shall be avoided when assembling and disassembling the tool.
After assembly, check whether the tool root runout is less than 0.01mm. If it is out of tolerance, it shall be corrected by repeatedly loosening and tightening and adjusting the contact surface of tool handle. If it is not improved, check whether each contact surface is in normal state, and avoid random knocking.