Tab choices when cutting polycarbonate

Hi All,
I have successfully cut 3/8" polycarbonate for a project. Now I am trying to refine the tool path to make the run time shorter.

I have a 1/4" "O" single flute bit that works beyond any expectation. I was taught to set the cut depth to 1/32" and the speed is 18K ; I forget the IPS feed rate but it worked.

The project is basically a 3.5" donut with a 1" center hole. I use four tabs set 90 degrees apart. The tab size is 0.125" and 2D in profile. I was taught to use ramp in cuts.

Does anyone have suggestions on how to speed up the total job time? I was thinking that my cut depth per pas could be increased to 0.0625 or even 0.125" with the same speed and feed rates. Would a 3D tab be a faster profile? Would going to a 3 tab arrangement still provide part stabilization?

Thoughts?

thanks,
Clint

Use 3D tabs, but maybe increase the length slightly to add some strength to it due to the fact that it ramps up to the 0.125" height instead of going straight up. Keep in mind that the actual tab length is tool diameter shorter than the setting. Set the plunge rate to be close to or the same as the feedrate. This will allow the toolpath to maintain a more consistent feedrate instead of having to slow down for each 3d tab.

As far as your other thoughts, give them a test to see how the quality holds up.

One thing I've found with tabs in acrylic. Unless you are very careful, you can knock a chip out of the good side of the cut when removing those tabs. I use a multi-tool (ultrasonic) to cut those little buggers so they don't ruin the good side.

I would say going deeper per pass may cause more problems than solve. The forces go way up and the odds of getting melted plastic in the kerf go way up.