HSMAdvisor operates both in imperial(in) and metric(mm) system.

Every field on the main Speeds and Feeds tab can be toggled to either in or mm simply by clicking on the in/mm label, located next to the field.

The value will be converted automatically.

For example if you enter 0.5 in diameter, you can convert it to 12.7 by clicking on the in label like so:

It is totally normal to have some fields metric and others imperial.

For example this setup is totally legitimate and HSMAdvisor will internally use proper units for each field:

Changing Speeds and Feeds Page Units Globally

While HSMAdvisor's Speed and Feed page is designed to work with both units simultaneously, for user's convenience we have added not one but two global switches that toggle all units on the page to either inches or millimetres:

Clicking Input in/mm label will toggle units for all Tool Geometry and Cutting Parameters fields.

Clicking Result in/mm label will toggle units for all Speeds and Feeds and Gauges fields.

Please note that these global in/mm switches do not change units for other pages and windows of the app. They only apply to the fields of the Speeds and Feeds page.

Units In the Machine Definition Page

Machine Definition page always starts up in same (imperial) mode.

For purposes of editing or creating your machine you can toggle the in/mm radio box to have your machine parameters fields displayed in either one of those systems.

As you toggle between imperial and metric values will automatically convert from one unit system to another. While doing so a small rounding error may appear. But it is designed to be not significant to the overall calculations.

It does not matter whether you save your machine with in or mm flag set.

The unit system set in your Machine Definition DOES NOT AFFECT speeds and feeds calculations in any way. HSMAdvisor will internally handle all conversions and output result value only depends on the unit currently set for each displayed field.

All you have to worry about is for the numbers to be actual for the currently selected unit mode. 

See also 

HSMAdvisor Units System (in/mm)
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