Acrylic Cast Vs Extruded?

I’d like to buy a few thin sheets of acrylic for a couple projects i’ve been working on. I’m just curious how much of a difference cast makes vs extruded? I plan to do some basic cut outs for some signage. Some painting might be involved also. I understand cast cuts better but for my intended use, would cast make much of a difference? Just trying to determine if i can save a few bucks going with extruded or not. Thanks.

You want to buy cast acrylic if you plan on machining it.

Cast acrylic cuts well if you use proper feeds and speeds.

Extruded acrylic will gum up your bit, and after a short run, you will have a lovely melted blob of acrylic on your bit and it will break. This is from personal experience before I knew the difference between cast and extruded.

I was trying to engrave the plastic with an 0.0236" (0.6mm) bit, and it cut for just a second or two, then began the “making a melty blob” phase, then moved quickly to the “snap off the bit tip” phase, which prompted me to look up why it happened.


I agree about using cast acrylic instead of extruded. Extruded is soft and flexible, cast is hard and brittle. The brittleness extends to the problem that cast acrylic can be broken like glass, especially if there are any scratches or score marks or if there is a pinched or thin neck sort of place in the design.

Have you considered sheet ABS or styrene. I’ve used ABS for many years and it machines very well.

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