As a general rule, select the largest diameter and most stiff cutter that you can use for the features you're cutting.
- Standard 1/8" ball end mill (2-flute, ~3/4" flute length)
- Contouring and part smoothing
- Standard 1/8" flat end mill (2-flute, ~3/4" flute length)
- facing, 2-1/2"D work, roughing contours
- 90deg chamfer end mill
- edge breaks, engraving, and spot drilling.
- Standard ball end mills and tapered finishing cutters
- Drafts (molds)
- Smaller diameter - micro-grain carbide dead sharp tools with 2 or 3 deep flutes and high helix angle are good for plastics.
One half of the tools can be long-reach (40mm max) the other half will be shorter (25mm max). For the longer tools, undercutting 300deg ball end mills allow finishing of high-vertical-sidewall parts.
Flute length is not important unless cutting deep pockets close to the size of the tool. Generally, we don't take many cuts with the full length of the side of the end mill, except occasionally finishing passes of .02~.04mm.
We typically only use single form thread mills. They are a bit slower since you have to sweep the entire helix, but they're also the most versatile. Multi-form tools are typically for production situations where you are only cutting one thread pitch and you want to minimize cycle time. These are not generally available with 1/8" shanks.
Difficult to find with a 1/8" shank. The staggered tooth versions are much better at clearing chips, which is extremely important with thermoplastics. We are working to source these as a custom solution for the H-Series.
We use both 60 and 90 degree tools with flutes (true chamfer end mill, not just a pointed engraving cutter)