The MonsterMill PCR UNI plunge mills from Sheffield-based WNT (UK) Ltd (www.wnt.com) are said to allow precise and process-secure ramping/plunge milling at high angles, or with extremely high chip volumes, during full-slot milling in materials such as steel, stainless steel and cast iron.

This capability is made possible by the cutters’ four-flute design and patented centring tip.

With four cutting edges, the MonsterMill PCR UNIs offers an advantage over conventional plunge mills with only three, as they can achieve feed rates that are up to a third higher.

For ramping/plunging, slotting and profiling operations, feed rates of up to 0.137mm/rev are possible, according to WNT.

Even when used at high cutting speeds, these tools offer process security, thanks to the use of a core geometry that has been designed to break chips and prevent spiral chips forming during plunging and drilling.

They also offer a quiet cutting action; this is attributed to the irregular flute pitch and helix angle, which have the effect of preventing the tool from oscillating — even when ramping angles up to 45deg are used without reducing the feed rate.

Another feature of the PCR UNI cutter is its ability to ensure a stable process and maximum precision during angled ramping at up to 90deg.

This stability is achieved as a result of the patented 142deg centring tip, which allows rapid centring without having to perform helical milling in advance.