In article , Michael Chare wrote:
a) Why aluminium has largely replaced steel as a material for
metal window frames?

Steel window frames are welded then galvanised. Definitely a process
for big company mass production. Aluminium windows are made up from
extruded sections and joining pieces so almost anyone could start
making them with a relatively small outlay.

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Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
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