Mechanical Methods

Mechanical methods include techniques such as screw fastening, riveting, or snap-fits which employ a fastener or physical means of part assembly. These techniques are used for applications requiring non-destructive disassembly or rapid assembly with low capital investment. Unlike other fastening methods, these techniques are readily used for joining all materials, including metals. Plexiglas acrylic resins may be joined with themselves or other materials, providing appropriate design considerations have been taken.

Accumulation of material, not only in walls, but at joints and corners should be avoided by coring out. Good practice aims at minimizing risk of sinkmarks, voids and deformation in the design process.

Snap-fit assemblies must be designed within the elastic limitations of the materials employed. The following formulas may be used to estimate the percent deformation of Plexiglas acrylic resin for a given design.

For Cantilever: e = d/(0.67 x l²/h)

For Bush Fit: e=(d1-d2)/d1 x 100
ß angle range for a dismountable system = 40-50°
ß angle range for an undismountable system > or = 50°
a angle should be between 20° and 30°