Pinning

Pinning is an assembly technique where a small hole is drilled into two parts that will be glued together, a length of wire or plastic rod is inserted into one side, and the other part is glued on so the rod bridges the joint. The rod adds mechanical strength that glue alone cannot provide, especially on load-bearing points like a weapon arm or a model balanced on one leg.

This matters most for heavier resin models, models with thin points of contact, or pieces likely to be handled and transported often, since a glued-only joint can snap under stress or over time as the glue becomes brittle. Pinning also helps align parts precisely during assembly by giving you a guide to slot pieces back together the same way each time.

A pin vise and matching drill bits, sized to the wire being used, make clean, straight holes far easier than trying to drill freehand. A common mistake is drilling the hole off-center or too shallow, which weakens rather than strengthens the joint, and using wire too thick for the part, which can split thin plastic or resin instead of reinforcing it.