If you have engaged cutter compensation, you can not reverse the trajectory 180 degrees. You must program something of that nature on the centerline of the tool. You must enter <CNI> & <enter> and it must occur before and after the Screw Corr. appears in the lower left corner of the screen. For most NC481 / RT480 machines, if anything you would want to reduce the speed settings for age / wear of the machine. I believe most of the older machines were set with a 55-60mpm max rapid.
Hope this helps
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