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In addition to standard drilling applications,the revolutionary self-clamping CHAMDRILL mechanism is an excellent solution for special drilling requirements. Pre-thread hole drilling is very popular in many industries. Available are drills designed for M8 to M24 ISO M standard pre-thread holes.
The new DCT drills carry two standard chamfering inserts designated AOMT 060204-45DT IC508, symmetrically mounted and cutting forces are balanced for optimal performance. This feature is essential in through hole applications.
Counter boring may be performed, however it is limited to a 6 mm depth.
Unique Chamfering Inserts
The AOMT 060204-45DT IC508 chamfering inserts were designed for chamfering and counter boring on a wide range of materials with optimal chip formation. The insert has an IC08 submicron substrate and is TiCN +TiN PVD coated.
New CHAMDRILL 6.8 mm Pocket Size
In order to be able to drill the pre-thread hole for the popular M8 thread size, a new 6.8 mm pocket was designed. This pocket can carry a range of drilling heads from 6.8 to 7.49 mm.
Advantages
- Can be used on a wide range of workpiece materials.
- Can be used for blind, as well as through hole, applications.
- No vibrations during chamfering due to a balanced drill construction.
- 1.5 mm x 45º chamfer is possible when the recommended drilling conditions.
- Provides diametric versatility – CHAMDRILL is capable of using a range of drilling heads on each drill body.
This provides a substantial advantage for users who change drills for the same tap operation. The user can use the same DCT drill for ISO M (coarse pitch thread) and for ISO MF (fine pitch thread).
Machining Recommendations
- Machining recommendations used for the standard CHAMDRILL drills apply also to the new DCT drills for both drilling and chamfering - note that the same conditions may be used for chamfering.
- In counterboring, reduce cutting data by 10%.
- In case of chip formation/evacuation problems please try the following recommendations in the order presented:
- Reduce cutting data by 10%.
- Increase internal coolant pressure.
- Apply a pecking cycle.
- Before clamping a new drilling head, apply some oil in any CHAMDRILL pocket. This will reduce pocket wear and increase the number of indexing cycles.
Applications
- Shallow (up to 6 mm) countersink screw head applications.
- Can be used for both rotating and stationary applications.
- An excellent choice for applications requiring a 45 º chamfer.
- Replaces our special drills that were designed for pre-thread hole applications in order to reduce cost and unnecessary handling.
- DCT (M8-M24)