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The programme examines the overall design philosophy necessary to produce a single mass-produced article; in this case a plastic potato chitting tray.
Metadata describing this Open University video programme
Module code and title: T351, Materials under stress
Item code: T351; 12
First transmission date: 28-08-1976
Published: 1976
Rights Statement:
Restrictions on use:
Duration: 00:23:06
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Producer: Philip Ashby
Contributors: Ron Jones; Peter Powell
Publisher: BBC Open University
Keyword(s): Chitting; East Anglia; Environmental conditions; Moulding constraints; Prototype parts; Stacking; Trays
Footage description: Ron Jones, in a cattle yard on a farm in East Anglia, introduces the programme. Jones, inside a farm building, explains the chitting process for producing seed potatoes. He shows some chitted potatoes to illustrate his points. Jones explains why plastic chitting trays would have some advantages over traditional wooden trays. He points out why a plastics designer would not make a Chinese copy of a wooden tray and also points out some of the critical elements in working conditions during the life of the tray. Peter Powell (Institute of Polymer Technology, Loughborough), the designer of the plastic tray, and Ron Jones discuss how the main structural members of the plastic tray were designed to prototype level. Powell and Jones go on to discuss the importance of taking time dependence into account in the design of the plastic tray. Powell and Jones examine a prototype plastic chitting tray. They list additional design problems which need to be considered before a final product can be manufactured. Ron Jones, inside a plastics components factory in Birmingham, looks at some of the products which are manufactured by the injection moulding process. Shots of two injection moulding machines at work. Commentary by Jones explain how they work. Jones goes on to point out several examples of design constraints imposed by the manufacturing process. Powell and Jones (back on the farm) look at a plastic chitting tray in its final form. They point out and explain the changes which have been made in the design since the prototype was produced and the reasons for making the changes. Jones and Powell briefly discuss the problem, for the designer, of material selection. They explain why poly-propylene was chosen for chitting tray manufacture. Shots of plastic chitting trays being abused in various ways on the farm including being run over by a tractor. The demonstration is intended to illustrate the strength of the design. Commentary by Jones.
Master spool number: 6HT/72150
Production number: 00525_5263
Videofinder number: 1423
Available to public: no