Cutting StarBoard on the CNC

Advice on feed rates, RPMs, and bit choices for cutting StarBoard high density polyethylene on the CNC. December 28, 2014

I have to cut 3/4'' starboard on my CNC and need advice on the tool type, rpm, and speed. Any help is appreciated.

Forum Responses
(CNC Forum)
From Contributor H:
We have had the best results cutting this with our 3 flute slow spiral upcut. Since this is a plastic you need to get those chips out (14,000 to 16,000 RPM at 200 to 400 IPM as a starting point). Always start low and work your way up. A lot is going to depend on the diameter tool you use. Half is best if you can and the size of the part being cut. Always check and change collets.

From contributor T:
I was just cutting some of this the other day with a 3/8" carbide offlute (1" length of cut) at 17,000 rpm and 175 ipm (approximatley 4.5mpm). This application required exceptional edge finish so we did several roughing passes leaving .012~.015, then one finish pass. It cuts very well! I would think in most applications that do not require a surface finish measured in micro inches, you could cut substantially faster (feed rate).

From contributor Y:
Starboard can have a slight warp in the sheet from time to time and this causes issues when cutting or trimming finished parts. Some folks I know have used either a 1/32", 1/16" or even 1/8" sealant in order to create a better vacuum seal between the substrate and the spoilboard.