The plastic core of ALUCOBOND^® eco can be hot-air welded using conventional hot-air welding equipment and plastic filler rod. Hot-air welding is not suitable for joints where structural strength is required.

Hot-air welding has proved useful for joining thermoplastic plastics and for welding ALUCOBOND^® eco. The plastic core and the plastic welding rod are heated and welded using electrical hot-air welding sets. The following conditions are essential for good results:

• Well prepared welding joint
• High-quality welding rod
• Clean hot air
• Correct temperature
• Correct contact pressure
• Welding speed

(Fig. 1) The rapid welding nozzle method ensures uniform heating of the core material and the welding rod and thus results in a better welding quality. Rod A is inserted manually through nozzle tongue B. By applying constant pressure to the nozzle tongue, the rod is pressed into the joint.

For butt-welding, the edges of the ALUCOBOND^® eco panels must be chamfered (Fig. 2). Before folding and welding ALUCOBOND^® eco panels, grooves have to be routed into the panels using corresponding milling cutters (Fig. 3). As the plastic core oxidizes relatively quickly when exposed to air, welding should be completed within 24 hours after chamfering.

Make sure to use the following quality:
Polyethylene, soft, Type: 1800-h, colour: black, rod diameter: 3 - 4 mm
Immediately before welding, remove the outer layer (oxide layer) of the welding rod using emery cloth. Please chamfer the starting end of the rod to approx. 45°.

The following air temperature is required for hot-air welding:
ALUCOBOND^® eco 265 °C ± 5 °C

The temperature must be continuously adjustable and is measured using a mercury thermometer or bimetal measuring unit 5 mm from the nozzle point. To measure the temperature, please take off the rapid welding nozzle.

The required pressure to the nozzle shoe (rapid welding nozzle) is approx. 3 kp.

A scraper blade or knife is used at a very flat angle to shave the welding seam as soon as it has cooled down. For visible welding joints, the seam on butt and corner welds is removed using a crescent-shaped knife (Fig. 4).