03-29-2012, 05:37 PM
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This is an article on how safety razors were produced in the 1930s. Many of the processes, though modernized with computer technology, versus human QC, is still in use today. Article Attached - Please forgive any scanning errors

Modern Mechanix 1937 - Behind the Razor Blade
by Robert W. Gordon

TAKE a look at any group photograph of half a century ago. No matter what their station in life, the faces of the men you see there will be adorned with luxuriant crops of whiskers. Some were clipped plain, with the simple dignity of a cemetery hedge. Others were brushed and trimmed in weird and wonderful designs, like decorations on a wedding cake.

Now take a look along the street any street in almost any country. You see a new race of men entirely. You can really see their faces, and they are bright and clean. No more of this hiding behind the bush. Their jaws are as bare of foliage as an oak tree in January.

Has science given us a new race of whiskerless males?

You know it has not. The whisker crop is as bountiful as ever, but it is harvested earlier harvested every morning by the majority of men throughout the world.

Now the only conclusion we can draw from this is that men never really liked whiskers any more than did the women. But down through the centuries, elimination of the beard remained an ordeal.

Then along came King C. Gillette in 1895 with the safety razor. Whiskers didn’t disappear over night. Men were proud of the wiry toughness of their beards. You couldn’t convince them that a little piece of metal stuck into a miniature double-edged hoe, could make shaving a painless, two-minute chore.

Even those few with faces too handsome to conceal, who went through the daily face-scraping with much the same martyr-to-looks spirit a woman assumes when getting a permanent, demanded a great steel forging, laboriously hollow ground, and equipped with a fancy handle. It required a lot of stropping and honing to keep a keen edge on that forging they called a razor.

Gillette had the revolutionary idea that it was only the edge you shaved with, and that the rest didn’t really matter. He popularized shaving by developing an edge so sharp it is invisible, yet so cheap you can throw it away after using it once.

And the edge of the razor blade actually is invisible, even when looked at through the highest-powered microscope. The cutting edges of 80.000 blades, laid side by side, would occupy only one inch of space.

They demonstrate this absolute invisibility at the factory in Boston. They will show you a stack of blades a foot high, clamped together on a special holder. So accurately are the blades cut that the unsharpened ends appear as one solid bar of shining steel. Now turn the stack on edge. You see no shining metal there only solid black. There is not enough metal on the cutting edges of that stack of blades to reflect a single beam of light. You can photograph it and get nothing on the plate but a solid black rectangle. Place a single blade on its side under a high-power microscope, and there will be no saw-tooth effect only a straight line. Place the blade on edge and you will see nothing. One-eighty-thousandth of an inch is too infinitesimal a point in space to be seen by the eye, even when aided by the highest-powered microscope science has produced.

To obtain a cutting edge so sharp, close control and microscopically-fine limits of accuracy are required for every operation of manufacture.

Swedish steel is used because of the high quality of Swedish raw materials and the long experience and great skill in rolling possessed by the Scandinavian mills. To insure uninterrupted production schedules with accompanying uniformity of quality, a tremendous steel inventory, representing an investment of several hundred thousand dollars, is carried in storage.

The coils of raw steel arrive from Sweden, each wrapped in heavy crepe paper, covered with oily waterproof paper, while the surfaces of the steel ribbons are coated with a special rust-proofing compound. Six coils are hermetically sealed in a tin container, which is protected by a wooden box. Thus protected, the shipping case could be immersed in sea water without damage to the contents.

As the cases are opened at the factory, a sample is cut from each end and tagged with the number of the coil. Another tag is placed on the coil itself, and follows the steel throughout the factory until the finished blades are packed. Each person who handles that particular coil, whether for manufacture or testing, must initial the tag. When the coil passes from one stage of manufacture to another, it is checked in and out of the control room. This intricate system of checking and rechecking makes it possible to detect flaws instantly and trace them to their source. It makes it possible to guarantee that only perfect blades will be offered for sale.

The original samples of the soft cold-rolled steel are submitted to a series of rigid laboratory tests to see that specifications for width, thickness, and metallurgical characteristics are fulfilled, and only when these tests are completed, and an O. K. placed on the tag. is the coil released for production.

Width and thickness are checked by micrometer gauges, and the variations permitted are infinitesimally small. A sample is then placed in the oscillograph, an instrument that virtually sees through steel. Hidden flaws, strains resulting from improper rolling, incorrect micro-structure, are instantly detected.

Samples of each coil are then sent to the laboratory and microphotographed at 3,000 diameters. A trained metallurgist studies these photographs to determine if the inner structure, the combination of elements making up the metal, is suitable for blades.

Another sample goes into an electric furnace, to be burned in a stream of oxygen. Vapors resulting from this combustion are analyzed chemically to see that exactly the right proportion of carbon is present.

This chemical content is extremely important. Without the proper amount of carbon the steel will lack hardness. With too much sulphur or phosphorus, the steel will not yield a cutting edge that will stand up for a number of shaves. With too little manganese or chromium, the steel will lack toughness. Metal failing to meet these rigid laboratory tests is immediately crated and returned to Sweden. If approved in the laboratory, the coil of soft steel is wound on a reel and sent to the perforating machine. But before it reaches the dies it feeds through two series of oil wipers, which remove any foreign matter adhering to the strip and add an oil which aids the perforating die and prevents rust between this and the next operation.

These dies that punch out the center slot are the acme of accuracy. They must be if the blade is to be held in the razor at the correct position for a proper shave. Unable to obtain such accuracy elsewhere, the factory employs its own corps of die cutters, any one of whom could grind the print off this page without removing a particle of the paper.

So critical is the workmanship demanded here that in certain cases it has been necessary to release a man from his bench to other easier tasks for several months to prevent a nervous breakdown. The dies these men produce are accurate to one ten-thousandth of an inch.

After perforating, the blade strip is gauged for centrality a measurement from the center slot to either edge. This distance must be held constant. The importance of accuracy here can scarcely be over-emphasized, since centrality of the slot controls the proper positioning of the blade in the razor.

Since the hardening process requires a surface absolutely clean, the coils of steel are “laundered” in the de-greasing machine immediately before entering the hardening furnace. The de-greaser passes the perforated coil through a soda wash, through high pressure jets of water just under the boiling point, through blasts of compressed air, a scrubbing box, a tank of special grease solvents, through jets of live steam, and finally compressed air again.

The razor blade makers were the first to recognize the fact that steel received from the rolling mill cannot be uniform, even in a single coil, and that to produce a uniform finished product, the temperature of the hardening furnace must fluctuate to compensate for these variations.

Since the furnaces maintain a temperature of approximately 1500 degrees Fahrenheit, and the difference between a good and a bad blade can be affected by a change of only 10 or 12 degrees, the control for the hardening furnace must be extremely sensitive and entirely automatic.

A “magic black box,” situated midway of each furnace, furnishes this automatic control. A master strip of steel of exactly the correct temper is inserted in this box. If the steel in process does not match this master strip exactly in hardness, the magic box flashes an impulse to a control panel regulating a battery of automatic switches, and the amount of electricity flowing to the furnace is altered the required amount to bring the steel to the desired standard.

It is in the hardening furnace that the distinctive blue effect of a blade is obtained. A patented apparatus feeds a special mixture of gases to the furnaces, and the blue becomes part of the steel itself.

As the strip of steel leaves the hardening furnace it passes through the tempering plates that make the center section easy to flex when the blade is placed in the razor. A coat of rustproofing oil is then applied before the coil is rewound.

Samples are broken off of each coil after it leaves the furnace, to be submitted to a hardness test under a diamond-pointed instrument. If a sample fails to meet the required standard the whole coil is rejected and the furnace is stopped until the trouble can be found and remedied.

These samples are then sent to the cathode ray oscillograph the electro-magnetic tester previously described. Variations of hardness and temper, or any hidden flaws or strains, are revealed here by a green line of light flashing on the fluorescent face of the oscillograph cathode ray tube. So accurate is this device that the passing of a sample through the flame of a match will cause a variation of hardness great enough to bring about a rejection. Next is a bending test to make sure the center of the blade will flex in the razor.

Having passed these tests, the coil of steel, now perforated, hardened and tempered, is run through a series of delicate gauges, to again determine that the breadth, thickness and centering are uniform.

The approved steel is again passed through the “laundry,” after which it goes to the etching machines, where the trade mark and other distinctive lettering are etched on the metal with acid.

After another examination, the coil is sent to the sharpening machine. Two sets of grinding wheels, one for each edge, first remove the rough stock. Next the honing wheels, cutting at a different angle from the grinders, produce a perfect bevel on each edge.

After being honed, the blades are washed clean and dried with compressed air before passing on to the stroppers of specially tanned leather. Each blade is finished on 280 feet of sharpening surface while passing through this machine. Inspectors stationed at the ends of the finishing machines submit their blades to tests with microscopes and gauges, finishing the test by cutting hair with the blades.

Samples from the finishers are also sent continually to the laboratory for examination by a photo-electric sharpness comparator. This machine measures the area of the blade edge with a beam of light. As the light traces down the length of the blade, a dot is thrown on a ground glass.

With cross-section paper placed over the glass, a girl traces a graph of the blade’s edge. If the graph is straight, or nearly so, the blade is satisfactory. If it is saw-toothed, irregular, something is wrong with the grinding machine. That machine is stopped immediately, and the blades it has finished must be rejected.

The finished blades now go to a room which at first glance you would take to be a library. Girls are studiously pouring over, not books, but stacks of blades. Every blade that leaves the factory is inspected by these girls.

After passing this last barrier the blades are sprayed with a powerful antiseptic solution, after which they are immediately wrapped, sealed in a wax-paper envelope and an outside wrapper.

In an endeavor to improve its product the Gillette Company has several inventors on salary, constantly working on new developments for the razor and blade.

And all so you won’t wear whiskers.

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