Different manufacturer of annular cutter have their own different design and geometry. But, the main two types of design are the Half Flute Annular Cutters and Full Flute Annular Cutters. Below article gives more details on Why Fully Flute Annular Cutters are technically much better than Half Flute Annular Cutters,
A full flute is an advanced design than the half flute. Some manufacturer produces half flute cutters only for their production cost cutting. The half flute has no advantage on drilling, In fact, it is an old technology compared to the full flute designed cutters. Many good manufacturers from Germany, UK and USA have only full flute designs. Please also check the websites of Milwaukee, BDS Maschinen, FE Powertools, DeWalt, Haugen, etc.
A. Why is a full flute better than a half flute?
1. When drilling deep holes, the flutes work as a track or travel for the chips to come out of the hole.
2. In full flute design, the chips can easily travel the complete length of the cutter and come out of the hole. Thus it does not block or jam the cutter.
3. In half flute the chips can travel only half distance, thus they very frequently block the or jam the cutter. Hence giving the poor life of cutter.
B. Why some manufacturer produce half flute design cutter?
Only and only for cost reduction by taking quality into risk.
C. Why some dealers encourage end user to buy half flutes?
Firstly because of ‘’superstitious!!’’. Secondly, no technical education and third, because they do not have other visible arguments to make to sell against the good quality manufacturer.
D. Why do professional manufacturers not manufacture half flute?
Because of its more than 15 years old technology and not an advanced technology.
E. What is the technical proof/reference to above arguments?
Click on this link for literature on drill bits and flutes, written by By Robert H. Todd, Dell K. Allen, Leo Alting