Gas welding for plastic has been around for decades. The Swiss company’s introduction of a hot air gun that had a very exact temperature control made it possible to use this method for fabrication and plastic repair.
It was not until the release of Ford Escort MK4, Austin’s Maestro, Montego and the Rover 800 series ( These sites have pictures and histories www.maestro.org.uk and for the Rover www.aronline.co.uk ) and other makes along these lines, that a good reliable way of repairing flexible materials needed to be found. The traditional method of the fiberglass patches behind the damaged area as support had to change.
It did not take long for the Insurance companies to realize that they could not sustain the replacement costs of all these bumpers. The type of plastic used in the Austin and Rover ranges would not take much of a knock before it shattered. The insurance lab’s at Thatchem ( www.thatchem.co.uk ) had to find a way to cut costs.
It did not take long for two systems to come to the fore; two pack polyurethane and plastic welding. The two pack procedure still required with some repairs, a patch behind it, this limits it to the smaller repair. As to the welding, it can cope with the full gamut of damage from a small crack to broken pieces. It became clear that this was the way to go.
At this point I must point out that flexible materials fall into two categories:- thermoplastic the injection molded type that repair by gas welding and the other is thermo-set; this is where two chemicals added together form a solid like two pack polyurethane and glass reinforced plastic (GRP).
Plastic welding has come a long way since the early days. The Institute of the Motor Industry recognise it as a valid repair for plastic parts and has become part of the body repair apprenticeship. It only takes a few hours to learn the basics of plastic welding but it is a skill that takes some time to perfect, more so when it comes to broken and missing pieces.
The motor industry is introducing more and more plastic into its products, part of the reason is to cut costs, another to make vehicles lighter meaning they will go further on a tank of fuel and in the current climate of higher energy costs this is a good thing. But where will it stop? In the future the plan is to have the vehicle made of plastic right down to the wheel rims. I know we already have GRP cars like TVR ( www.tvr-car-club.co.uk ) but I’m talking about thermoplastic cars that go beyond the Renault Espace (www.matrasport.dk ). It is possible that in the future, the engines that propel these cars could be made of plastic but that will depend on fossil fuels still being used.