Plastic welding is a technique to join pieces of plastic together using a a thermoplastic material, which can soften and create a secure bond. Common types of plastic to use in plastic welding include:
- Polyethylene.
- Polypropylene.
- PVC.
- Polyurethane.
- Acrylonitrile Butadiene Styrene.
How plastic welding works
Plastic welding works by heating a plastic rod to its melting point slowly and applying it to the area that needs to be connected or repaired. A heat gun is a common tool to use for plastic welding, as these devices are portable, easy to use and allow the heat to be carefully directed at the specific area that needs to be warmed.
A plastic welding attachment turns a heat gun into a tailored tool for this purpose. The attachment has three openings: one for the heat gun nozzle, one for the plastic rods and one for the plastic and heat to come together in contact with the material being welded.
Plastic welds can take many shapes and angles. The right one for a job depends on the desired outcome. Two pieces can be conjoined atop one another with an edge weld, or two pieces can be welded in line with one another with single or double V welds. Corners and angles can also be welded with this method.
How to choose the right tools and materials for plastic welding
The various plastics used for welding have specific melting points, and they’re not identical to one another. ABS melts at 500 degrees Fahrenheit, while PVC melts at 525 degrees, polyethylene at 550 degrees, and polypropylene and polyurethane at 575 degrees.
Since plastic welding is often done for small, precise areas, the plastic welding attachment is used in conjunction with a pinpoint reducer, which acts as a funnel that narrows the heat stream to a smaller diameter.
When choosing a heat gun, keep these melting points in mind and check the thermal capacity of the tool. Some heat guns are designed for lower temperatures, while others will overshoot these targets.
