High Speed Machining is becoming more and more popular each day.


While definitions of HSM may vary between tool manufacturers and even individual shops, the physics behind it remain the same.

High Speed Machining is a complex of programming, machining and tooling techniques aimed at radical increase of productivity.

Chip Thinning and HSM machining switches allow HSMAdvisor to account for the effect of thinning chip in certain machining modes.

Here is a list all the possible machining modes that cause chip thinning:

  1. When side-milling with any kind of end mill at low radial engagement angles (Width Of Cut below radius of the tool)
    This machining style often requires special CAM software with HSM tool paths that makes sure your engagement angle never exceeds the amount you have calculated your Speeds and Feeds for.
  2. When machining with radiused tools (such as ball or bull nose end mills) at Axial Depth lower than the Corner Radius of the tool (WOC below radius of the tool)
    When machining with cutters that have Lead Angle below 90 degree (such as 45 deg Face Mills, Feed Mills)
    This machining style employs regular pocketing and profiling tool paths programmed with large WOC (Radial Engagement) and low DOC (Axial Engagement) values

What are effects of thinning chip on cutting process

  • Improved chip evacuation: because of low engagement values chips are less likely to clog the flutes.
  • Less contact time: Allows for higher Cutting Speed
  • Better distribution of load over the length of flute: higher feeds and more MRR (Material Removal Rate) possible.
  • Longer life of the cutting edge: lower engagement improves conditions for each cutting edge
  • Longer tool life: wear spreads over longer portion of the flute: instead of only using the end of the cutter, you are using a whole flute

How HSMAdvisor accounts for chip thinning

  • Chip Thinning check box allows you to increase the Chip Load or Feed Rate when conditions, required for thinning are present (see list of machining modes above, that cause thinning)
  • HSM check box allows you to increase Cutting Speed or RPM when chip thinning occurs

These switches is independent of each other and account for both aspects of thinning chip phenomena

These switches only make any difference when chip thinning actually occurs!

When to use Chip Thinning and when to use HSM check boxes

Use Chip Thinning check box when you need to increase cutting feed rate to improve productivity and increase the tool life

Do Not use Chip Thinning check box when finishing walls and floors as it deteriorates surface finish

Use HSM check box any time you need to increase cutting speed, it is very useful for profile and surface finishing walls.


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Chip Thinning and HSM - High Speed Machining
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