SAE AMS-L-P-391

Description / Abstract: The sheet, rods and tubes covered by this specification are intended for use in applications where transparency, color range, weather resistance and other characteristics of cast acrylic shapes are required. Type I material is intended for use where the ultraviolet light absorbing properties specified in tables I or II, as applicable, are required. Type II material is intended for use where the ultraviolet light absorbing properties, specified for type I material, are not required. Type I and II sheet are not intended for use in aircraft glazing or other applications requiring consistently high optical quality. Type III sheet is intended for use in applications requiring good optical quality, cleanability or serviceability under adverse environmental conditions. Applications include diffusing lighting shields, window glazing, card holders, chart covers, edge lighted signs, surgical instrument handles and parts, safety shielding and transparent models. Type III sheet is not readily cemented using conventional cements for acrylic resins. The coating can be removed by sanding or buffing the areas to be cemented. Continuous cast sheet have better thermoformability then cell cast sheet, and the continuous cast process is less expensive. However, it should be cautioned that, if the continuous cast sheet are to be used in forming applications, frequently adjusting (temperature, pressure, time of forming cycle, etc.) of the forming machinery may be required and this could offset any savings. Due to the continuous mixing, the uniformity of blend for the continuous cast sheet may be less consistant than that of the cell cast sheet which is cast from a premixed batch. Also due to the ripple effects (waves) the continuous cast sheet may be marginal in use for applications such as optical windows.