The design of the adhesive joint will play a significant factor in determining how it will survive service loads. Although it may be tempting to use joints originally intended for other methods of fastening, adhesives require joints of a special design for optimum properties. The practice of using joints designed for some other method of assembly and slightly altering them for adhesives can lead to unfavorable results.
As with most fundamental processes involving adhesives, joint design cannot be complete without consideration of numerous factors. For the purpose of this paper, the reader should get accustomed to the fact that the joint strength is not necessarily the same or even proportional to the intrinsic strength of the adhesive. Joint strength is determined by many variables. The following variables are most important and are the primary subject of this paper.
* Adhesive material properties
* Adhesive thickness
* Geometry of the bonded area
* Adherend properties.
One must also be familiar with the requirements and costs of machining and forming substrates into various joint designs.