THREE X = SAFETY

THREE X SAFETY

NE of the greatest improvements in motor car safety in recent years has been the widespread use of safety glass. As in most other cases of progress, sports and racing cars led the way, their drivers fully realising the risk of flying glass splinters in an accident, until now this danger has become fully appreciated, and it is compulsory for manufacturers to fit the windscreens of new cars with some form of safety glass.

It was therefore with great interest that on the invitation of the Triplex Safety Glass Co., Ltd., we made a tour of inspection of their admirably equipped and organised works at King’s Norton, near Birmingham, when we had an opportunity to see for ourselves exactly how the famous Triplex glass is made.

As usual, we found that the business of making what outwardly seems a fairly straightforward article, can be a very lengthy process, especially, as is the case with Triplex, when the highest standard of workmanship is maintained.

On arrival, we were taken first of all to the Stores, where all supplies of raw glass, both plate and sheet, are carefully inspected for blemishes—a most important precaution. From there the glass is taken to the cutting room, where some twenty men and boys bring the rectangular pieces of glass to the required size by means of template and diamond. The patterns are all on the large size, to allow for smooth finishing.

Now let us leave the glass for a moment to consider another ingredient of the finished product, namely the celluloid. Most of our readers are doubtless aware that safety glass consists of a “sandwich,” composed of two sheets of glass and a sheet of celluloid in the. middle. The celluloid is supplied by the manufacturers, and has to be graded and inspected in the same way as the glass. It is then cut into the requisite shapes, by means of sharp knives, and passed on to the assembly room.

Meanwhile the shaped pieces of glass, after a further inspection, are washed, sprayed with hot water, brushed and rolled into a cage, where they are sprayed first with gelatine, and then with one of the many react compounds which are known only to the manufacturers. After this they are dried in long tunnels and then comes the preparation of the ” sandwich ” which comprises the finished product. The glass and celluloid come

together in a machine which has a long V trough, lined with wooden rollers. The pairs of panes are laid in the trough so that one pane lies against each side of the V, and the celluloid is dropped in between them. Conveyor bands carry the panes along the trough, and warm water is sprayed over them. The spraying is then changed from water to another secret Triplex liquid which is known familiarly in the works as the “cough mixture,” for it is claimed to be a very good cure for both coughs and colds. The V narrows and the panes are brought together until they are pressed tightly between rubber rollers, and all the moiture is forced from between them.

The ” sandwiches ” are next carried to the hydraulic presses, of which there are over fifty. Gauges are fitted to assist the girls who attend the presses, but they do not tell the outsider anything, for the significance of the figures is known only to Triplex engineers. Sandwiching is one of the secrets of the whole process.

The sheets of safety glass are then ” arrissed,” that is to say, the sharp edges and overlap are ground down to the requisite size of the window of the car for which they are intended, after which an eighth of an inch of the celluloid is burned out by means of a hot wheel, and the cavity filled with the sealing material or” pitch.”

After a final polishing, and in the case of sliding windows, a grinding of the edge to 1/64th of an inch, the sheets are finally branded with the famous three X’s, the trade mark of the firm. On examination, if any of the sheets are found to be scratched or marked, they are sent to a department which is all red in colour, for the men in it use jewellers’ rouge for removing marks .from the surface.

The panes which are passed O.K. go to the packing department, where they are wrapped up and placed in felt-lined boxes, when they go all over the world. They are taken from King’s Norton by road, for it is found that road transport is not only quicker, but is safer than delivery by rail.

Triplex turn out some two million square feet of safety glass a year, and when it is borne in mind that each sheet is inspected nine times before it is counted perfect, it is easy to understand why its three X’s are famous throughout the world.