Carpet tape

Carpet tape is a high-strength, high-adhesion double-sided tape used in weapon construction.

Carpet tape is available in a variety of qualities - it is important to use only the high-grade indoor/outdoor variety with visible fiberglass weaving, as the "plasticy" looking indoor-only variety has little strength and less adhesion.

A recent discovery is a semi-generic brand of carpet tape sold by certain hardware stores in the upper midwest and manufactured by the "Custom Tape Company" (possibly this one). The Indoor/Outdoor version is thick and black and is both extremely strong (and stiff) and has a very sticky adhesive. It is a very strong alternative to DAP for use in weapon construction, even at the point of binding foam to the core of the weapon. It is ~$5/roll and can be difficult to find. The Indoor/Outdoor version comes in a blue and white box with a picture of someone laying down outdoor carpet by a pool.