Machine, clamping device and lubrification
for CrazyDrill & CrazyMill Hexalobe
General information
In the industry for metal work tools, shorter processing times are always in demand. At the same time, the requirements to the manufacturing precision and process reliability are growing. To fulfill these requirements, the "machine tool (all types of drilling machines) – spindle – tool – tool holder" system must be perfectly adjusted.
The following requirements have to be taken into account:
- For the machine tool: High level of stiffness, vibration isolation of the foundations, lightweight design of the moving parts, high concentricity accuracy of the spindle, pull-in forces of the machine spindle, intelligent and quick machine controls
- For the tool holder: High concentricity and balanced, friction-locked tightening of the tool
- For the tool: High concentricity, excellent balance quality (geometry and shank design), long tool life (tool material, geometry, coating)
Machines and clamping devices
CrazyMill and CrazyDrill Hexalobe can be used on turning or milling and boring machining centers.
Turning machine
- Driven toolholder 6.000 rpm, 3 Nm, 1kW (nominal)
Spindle recommendation:
- For an optimal use of the micro milling cutter, Mikron Tool recommends high-frequency spindles
High-speed spindles
When highest performance is required, high-speed spindles are recommended.
Characteristics:
- Concentricity: 0.003 mm (.00012“)
- Recommended speed: 40‘000 - 60’000 rpm
- Transition-free, adjustable speed spectrum
- High speed stability, also under stress
- Special steady run
- High performance with low weight and dimension
- Precise bearings
- Best reliability
Milling machine
- Minimum speed recommended 30'000 rpm (diameter milling cutter < mm (.039"))
- Minimum concentricity of the spindle 5µm (.00019“)
Recommendation clamping device:
- For an optimal use of the combined drill / micro milling cutter, Mikron Tool recommends a hydraulic expansion tool holder or, alternatively, a shrink fit tool holder according to DIN 69871
Hydraulic expansion tool holder
These ensure the high concentricity during drilling.
Characteristics:
- Concentricity: 0.003 mm (.0001”) (measuring point at 2.5 x D)
- Max. speed: 50'000 rpm / balance rate (G 2.5 / 25000 1/min)
- Precise concentric clamping
- High torque transmission
- Maintenance-free (closed system)
- No wear in the clamping diameter
- Longer (up to 4 times) tool life
- Adjustable clamping force
- Short tool change time (without additional devices such as, shrink fit device)
Application:
- High-precision clamping of tools with cylindrical shaft
- Universal tool holder for drilling and milling (roughing and finishing). Advantageous in the case of HSC processing (milling, for example on a small CNC milling machine) due to its shock-absorbing.
Shrink fit tool holder - shrink fit tool holder according to DIN 69871
These guarantee highest concentricity with secure friction-fit connection and form an optimal connection between the tool and the holder.
Characteristics:
- Concentricity: ≤ 0.003 mm (.0001”)
- Max. speed: 40'000 rpm
- Absolutely secure friction-fit force transmission
- Adequate for shaft diameter of 4 mm (.1575”) (3 mm (.1181”) are conditionally possible).
- Transmittable torque 2 to 4 times higher compared to the hydraulic-tool holder and the high precision collet tool holder.
- Average tool change time (shrink fit device is necessary)
- Suitable for machining in narrow spaces and interfacing edges due to the small overall construction size and longer versions
Application:
- Optimal for HSC machining, in particular also for smallest drill bits
- For milling and drilling tools with cylindrical shaft
Balance quality
The balance quality of the tool holders is specially critical in high speed machining processes. The best possible balance quality guarantees not only reduced vibrations of the tool but increases tool life, improves surface quality and above all, protects the spindle bearings.
Cooling lubricant
To achieve optimal results, Mikron Tool recommends using cutting oil as cooling lubricant.
Alternatively, emulsion of 8% or more with EP-Additives (Extreme-Pressure-Additives) can be used with good results as well.
The external coolant supply cools and lubricates CrazyMill Hexalobe, CrazyDrill Hexalobe and CrazyDrill Hexalobe Flat. In comparison to mills / drills with through-tool cooling such as CrazyDrill Cool (cooling exits automatically at the ideal point of the drill tip), external cooling must be ensured in such a way, that the cooling medium flows directly to the mill / drill tip, thus cooling and lubricating the drill perfectly and flushing away chips.
Work piece clamping
Work piece clamping is extremely important when milling due to radial and axial forces. Vibrations while machining affect not only surface quality and precision of the work piece but also tool life. Vibration free and stable work-piece clamping is therefore a must.