Classic cars certainly require more attention than new cars because of the way they were built.
There are great differences even between pre and post war classic cars.
In the years before WW1 cars were mostly built around a channel section chassis and the body was produced separately and then secured to it. At about the mid-1930s box section frames became popular.
Classic Car © flickr/111 Emergency
The bodies were made by hand using coach building methods that reached back beyond the 18th century. The bodies mostly were aluminium panels covering a wooden frame, usually of ash. The coachwork was simple but well proportioned. Coach building was labour intensive and required skilled workers.
Until the mid-1920s open cars were more popular than saloons. If manufacturers didn’t maintain their own body shops, they relied on coach builders for the supplies. And as most towns had at least one coach builder, it was possible for customers to get their individual coachwork.
Change came from America, when in 1912 Edward Gowan Budd set up a plant in Philadelphia to mass produce pressed-steel bodywork for cars. The Dodge brothers were early customers, and after WW1 the steel bodies became more popular in the United States. The parts were quicker to produce and required far less skilled labour.
During the 1930s many British manufacturers adopted pressed steel bodies, but hand crafted coachwork also persisted.
A big step forward was the unitary body construction which first appeared in Britain on the Vauxhall Ten Four of 1938.
