Epoxy adhesives are widely used to bond prisms in cantilever fashion to mechanical mounting surfaces. Typically, the adhesive is applied in a prescribed thickness to a raised land on the mounting surface. This land then defines the area of contact with the prism. In order for the bond to survive, this area should equal or exceed some value related to the ass of the prism, the manufacturer's specified shear strength of the cured adhesive and the anticipated maximum acceleration due to shock and/or vibration during shipment, operation and mishandling by the user. In this paper, formulas relating prism clear aperture, material density and acceleration loading to minimum bond area for a representative commercially-available epoxy are derived for several common prism types. Since these computations are based on nominal conditions and some approximations, they should be regarded as guidelines for preliminary design purposes. Experimental verification of the choice of materials, application/cure methods and of the specific interface design is advisable in critical applications.
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