Replaceable solid carbide cutting heads
- Published: April 2, 2018
Iscar has announced two new tools with replaceable solid carbide cutting heads: the Iscar Multi-Master milling line and the ChamDrill line in drilling.
Performance and accuracy characteristics have positioned the new tools to be functionally competitive with solid carbide designs. The versatility of these lines, where a head can be mounted in different bodies and vice versa where a single body can carry different heads, facilitates various assembly combinations and contributes to reducing items in tool stock.
Another important design approach - “no setup time” - characterizes these lines, as a worn out head does not require spending time on setup and can be replaced while the tool is still clamped in the machine tool spindle. This cuts cycle time and, consequently, reduces production costs. In contrast, replacing a worn out solid carbide mill or drill inevitably leads to a new setup procedure.
In addition, the concept ensures sustainable use of cemented carbide with all the associated advantages. The principle of “indexable” carbide tools has distinct merits and features strongly in tool design within the diameter range that is under discussion.
The minimal diameter of Multi-Master milling heads is 5 mm and that of SumoCham drilling heads is 6 mm, while the Multi-Master combined countersink heads for center drilling feature a minimal 1 mm diameter.
Iscar has recently introduced a new range of small size indexable rotating tools under its new Logiq line campaign. The company proposes several families of cutters with a nominal diameter of up to 20 mm. A brief look at some of these families can provide a clearer understanding as to whether the new tools will be able to breach the solid stronghold wall.
The new families of indexable milling cutters within the diameter range of 8-16 mm attract the most interest. They have several common features: the cutters carry triangular shape inserts with 3 cutting edges and the mechanical part that secures the inserts is represented by a screw. These families are intended for milling square shoulder or fast feed (high feed) milling. But here the similarity ends, and the difference begins. While the design of the Heli3Mill and Micro3Feed families for tool diameter 10-16 mm is committed to the classical principle of insert securing, by clamping screw through the central hole of an insert, the NanMill and NanFeed families for tool diameter 8-10 mm have adopted another concept.
Within such a small diameter range, the central clamping screw, as noted previously, does not provide an acceptable solution. According to the new concept, the screw is located above the insert, and the screw head plays the role of a wedge (Fig. 1). This approach provides reliable and rigid clamping, ensures a durable homogeneous insert structure with no hole, and allows insert indexing to be quick and simple.
It is predicted that these new families will be particularly effective in manufacturing compact parts and in machining small in size cavities, pockets and small parts utilized in industrial sectors such as die and mold making, as well as in producing miniature components.
A 1 mm change in size: is this a lot or a little? For indexable tools in the small diameter range, it makes a noticeable difference. Iscar’s new SumoCham 5 mm diameter drilling head represents an important step ahead in expanding the application fields of indexable drills (Fig. 2).
Within the small diameter range, indexable tools can offer precision and performance advantages that position them competitively against the more traditional solid carbide tools.