includes a pair of glazing sheets separated by an intervening marginal spacer frame formed to a required size and shape from strip material and marginally secured between the pair of sheets the apparatus comprises a frame forming mechanism which includes guides defining at least two paths for feeding required lengths of the strip material stops defining a position for the leading ends of the strip material as it is fed a plurality of bending stations arranged to bend the strip material on at least one of the paths to form frame corner angles at required distances from the stops and apparatus for joining the ends of spacer strip material which has been fed along the paths and bent thereby to form the frame application_number US 4302979 A description in fig1 sheets e g of glass not shown are brought along a feed conveyor 1 whence they are transferred to two parallel conveyors 2 3 of a panel assembly line a stockpile 4 may be built up at the start of these parallel conveyors 2 3 these conveyors are indicated as being divided into various zones where different operations may be performed on the conveyor line 2 sheets pass through a first zone 5 where their position and size can be checked they are then fed to a zone 6 located beneath a frame forming apparatus 7 constructed in accordance with the invention after a spacer frame has been formed there and deposited on an underlying sheet the sheet and frame.