Cast and Extruded Acrylic: A Mini-Guide

Clear acrylic sheet is fast growing in popularity as an alternative to glass in domestic and commercial environments. It can offer flexibility, light weight and strength far superior to plate glass and this makes it a terrific material to use where safety may be a concern. There are two key types of clear acrylic which prove most popular as glass replacements; namely cast acrylic and extruded acrylic – but what is the difference between the two?

The key differences between cast and extruded acrylic stem from the way the sheet is manufactured, which may make the material more suitable for certain applications. Cast acrylic sheet is made by pouring acrylic resin into a mould, and this process results in a sheet which displays high strength and transparency with a less uniform thickness. Cast acrylic is also superior in terms of impact resistance, chemical resistance and thermal stability. While it may be more expensive than extruded clear acrylic; cast acrylic is a reliable choice of material for glazing applications including skylights and even boat windows, and it is also great for thermoforming and complex machine fabricating.

Extruded acrylic is the more economical material out of the two, and it is made by extruding the resin on a production line. This results in a very uniform sheet which is suitable for general purpose applications and home DIY. Though less strong than cast acrylic, extruded acrylic sheets are still far more impact resistant than glass, half the weight and won’t splinter if broken. Many greenhouses and garden sheds are re-glazed with extruded acrylic because of this shatter resistance and the low levels of maintenance it requires. In fact both cast and extruded acrylic need only a little soap and warm water to clean dirt from the surface of the sheet, and a soft cloth should be used to avoid scratches.

If you previously thought Perspex sheeting was all the same, it is worth taking the time to research the differences between types of material before selecting the right sheet for the job. Many clear acrylic retailers have a lot of technical information and years of experience they can offer. Cut Plastic Sheeting, for example, are a leading supplier of cut to size acrylic who can offer advice on the best material to use for a specific job. They really know their stuff, and they supply all of their Perspex and acrylic sheets cut to size so you don’t have to risk breaking it when cutting it in situ. The free price calculator on their site really comes in handy too!