Lightweight American Joon from Scotland
Page 21
If you've noticed an error in this article please click here to report it so we can fix it.
rEHICLE doors manufacured entirely of glassfibreeinforced plastics which have been developed by Premix Inc, bf America, are now being broduced to customer pecification by the British ubsidiary, Premix Fibre-Glas ,td, 28 Firth Road, Houstoun :state, Livingston, West .,othian, Scotland.
These lightweight and orrosion-resistant doors are low standard on the Astro and ;eneral truck ranges proluced by the Truck and Coach )ivision of the General Motors 7orporation. They represent he first vehicle body cornbonents subject to mechmica! stress to be successully mass produced entirely of einforced plastics withbut use of metal supports or tiffeners. Premix claim an 8kg saving in weight for each loor (36kg per vehicle), and a eduction of nearly 50% in the lumber of component parts equired previously.
Each door comprises three :omponents. The inner panel s of Premi-Glas 1200 g.r.p. ,heet moulding compound, mith a 30% glassfibre content. The compound is pigmented to the desired colour, and a grained stitched pattern moulded into the surface to simulate vinyl. The exterior panel is Of Premi-Glas 7200 ultra lowLprofile automatic grade SMC, also with a 30% glassfibre content. The "backbone" of Ale assembly is provided by a full-length internal structural frame, which is compression moulded from sheet moulding compound incorporating 30% continuous glassfibre S and 20% chopped glassfibre. This frame is light in weight, yet has the strength to prevent any bowing or deflection under stress or at high speeds.
Premix overcame a deflection problem in the thin section surrounding the door window by orientating the continuous glassfibre reinforcement along the entire periphery of the internal structural door frame.
Overall size of the doors produced for General Motors is 1295mm x 865mm x 50mm thick, and the total weight of the three-part assembly is only 16kg.