The Best Plastic Routers Bits
Plastic routers bits have long been used primarily with CNC routers at high speeds, with very fast rates. As a result of testing and experience in the field, plastic routing tools with free cutting geometry have become more widespread, but not necessarily among shops that machine mechanical plastics. Plastic routing is best accomplished with tools that have a high rake and low clearance, though, which helps improve productivity and increase the luster of the surface finish.
Most shops that machine mechanical plastics use end mills running on CNC milling machines, which are robust cutting tools specifically designed for heavy loads, slower spindle speeds and lower feed rates. These plastic machining tools get in the way of the shop's ability to eliminate the chips that are produced during the plastic machining process, though. These are actually probably better for metals, and not mechanical plastics. Choosing the plastic routers bits for a specific job depends on the materials being used.
Mechanical plastics might be hard or soft, which is easy to see by looking at the chips that are produced. Soft plastic machining produces a curled chip, while hard plastic machining produces a splintered wedge. In most cases, it is best to use O-flute plastic routers bits for soft plastics, while V-flute tools are best for hard plastics. In most cases, though, it is the O-flute plastic routers bits that are used. These tools are made in straight- or spiral-flute styles, and the selection depends on which direction the user wants the chips to flow. For the most part, plastic routing with upcut spirals is effective to eliminate, and downcut spirals are better for re-cutting chips. There are clearly some new plastic routers bits on the block for machining and routing, and there is no such thing as a one size fits all tool for these tasks.