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View Full Version : cast versus extruded acrylic



bill gervais
08-10-2009, 6:46 AM
Hello Creekers,

Looking to do some work with acylics shopping around I see extruded and cast. I know it is a different process but what are the pros and cons when it comes to cutting or engraving? Best suppliers?

Nice suuny day in Maine!

Bill

Frank Corker
08-10-2009, 7:42 AM
Cast engraves and cuts well. Can be snapped or broken. Extruded engraves but not very well, cuts okay, more robust than cast and often used in safety glass situations.

Rodne Gold
08-10-2009, 10:48 AM
My suggestion is stick to cast , extruded is stressed and doesnt respond well to solvents or solvent based glues when lasered (heat stresses extruded a LOT) and often months after you have lasered a a piece , if cleaned or exposed to some solvents and theior vapours , it stress cracks.

The only real advantage to extruded is that is far more within reasonable tolerances as to thickness , cast is often more than + and - 10% off in thicknesses over a piece .. difficult to use for precise manufacturing. It's sometimes cheaper too

The advantage of cast is that it does not expand more in one direction like extruded (expands more in the direction of extrusion), it expands evenly..

The way to check what you using is to burn a piece , extruded burns silently and drips molten burning balls of acrylic , cast burns with a crackle and doesnt drip.

Michael Simpson Virgina
08-11-2009, 12:10 PM
Extruded has a nasty burnt plastic smell when cut. Stinks up my whole lab. Cast has much less of a smell.