Dormer PrametUnit 4 Lindrick Way S43 4XE Barlborough, Chesterfield, United KingdomT: 0870 850 4466F: 0870 850 8866
Select the correct cutting speed as shown in Dormer's Catalog and Product Selector
The use of suitable coolants and lubricants are recommended as required by the particular drilling operation. When using coolants and lubricants, ensure a copious supply, especially at the drill point.
Use appropriate cutting fluid for the workpiece material. Numerous different types of lubricant are available, including oils, aerosols and compounds. Some contain Chlorine which can result in staining of certain materials eg. Aluminium. In such cases, ensure a chlorine-free lubricant is used.
Swarf evacuation while drilling is essential in ensuring the correct drilling procedure. Never allow the swarf to become stationary in the flute.
In conventional milling, also called up milling, the maximum chip thickness is at the end of the cut. The feed movement is opposite to the tool rotation.
Remember, the pre-drilling sizes for fluteless taps are different to those for conventional thread cutting taps. During the drilling operation, always ensure that work hardening of the component material is kept to a minimum.
Select the most appropriate drill for the application, bearing in mind the material to be machined, the capability of the machine tool and the coolant to be used.
Where possible, hold the tap in a good quality torque limiting tapping attachment, which ensures free axial movement of the tap and presents it squarely to the hole. It also protects the tap from breakage if accidentally 'bottomed' in a blind hole.
When regrinding a drill, always make sure that the correct point geometry is produced and that any wear has been removed.
The characteristic feature of the milling process is that each milling cutter tooth removes its share of the stock in the form of small individual chips.