Bonding Polycarbonate

Adhesive bonding for polycarbonate water baths

The joints used to bond polycarbonate or acrylic water baths need to be both structurally strong and completely water tight. The joints we use are actually tee joints which are finished to make a rectangular box. The bonding is done using jigs to keep the pieces at right angles while the cement hardens.

The figure below shows a typical bond using ½” sheet. Prior to bonding, one edge is beveled at 12 degrees using a router or table saw, and the adjacent side is cut 1/8” larger than the final dimension. The pieces are clamped together in the jig and the cement is injected between the pieces with a full fillet. The cement shrinks as it hardens so it is important to overfill the gap as shown. After about 4 hours the excess material can be removed with a router.

The cement we use for polycarbonate bonding is IPS Weld-On 55, a slow curing, clear, colorless 2 component, 100% reactive polyurethane adhesive.