Acryllic vs "Normal" Bits

I have a friend who wants to do some acrylic. Do I need special bits for it? From what I can tell, they aren’t really any different, but I am not against getting them if they are needed/better.

I happened to research this topic this morning and found this thread that might be useful to you.

there are two kinds of acrylic extruded and cast. Cast cuts much better and is also more expensive.
Polycarbonate is much stronger than acrylic and cuts much easier. However it is typically about 10% more expensive and if you use white color about 50% darker/less transparent.

Acrylic tends to melt, if you are cutting small pieces you can freeze it or just wait until winter when the shop is cold. with any material you should not leave a cnc unattended, but expecially with acrylic.

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I did the some successful cuts with cast acrylic, but on a desktop cnc.
With the Maslow the feed-rates are very low, plus with a router the RPM are to high for the feed.
So the only option to transfer the heat away is with the chips.
I would not try the extruded acrylic. With the cast i would go for a 1-flute (higher chip-load) at max feed speed and lower Z until the chips are like tiny snowflakes.
Proper vacuum is also a must, as chips from the previous cut tend to make ugly plastic balls around the bit.

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