It all starts with the disc burner or "lathe" as often called, a stunning piece of equipment designed with a feed mechanism that rotates slowly and transport screw to move the cutting head across the radius of the disc. The precision of pencil-shaped cut, mounted on the head, cut a spiral slot states through a flat aluminum disc coated lacquer (acetate) by turning to a precise speed of 33-1/3, 45, or the old days, 78.26 rpm operating speeds standard phonograph.

Next the cutting head is installed on the lathe, it is simply a phonograph pickup in reverse, ie, the audio feed in and get mechanical motion out. Apart from its larger size, the style of a special court, and the spindle mechanism which moves the head in the registry to make the spiral groove, the inner workings are very similar. The recording pen is probably the most important component of the recording process, and was probably first used by Edison in 1877.

Diamond is not a good material for a cutting stylus, but is excellent as a breeding pen. Home cutting styli were commonly made of an alloy steel because it was cheap to manufacture, but most cutting styli for professional use are corundum, known as sapphire, which will last more than a diamond and produce superior recordings. From the earliest recordings on wax, recording spaces have been called by various names including instantaneous discs, lacquers, acetates, smooth cuts and others. The most accurate is probably "lacquer" by the fact that they are coated with lacquer with a compound of cellulose nitrate and acetate had little to do with it, although it has become a common name for a lacquer-coated disc, and many professionals still use the term "acetate".

"The waxing phrase" still exists to day, although the solid block of wax-olds were in use until shortly before the Second World War. Before there was no tape recording and had to be cut in huge blocks originally thick warm beeswax, basically. The final product before "process" became a single lacquered disk on which the grooves were cut actual recording. different degrees of "overhead" were offered by manufacturers, which is distinguished by the uniformity of coating and the thickness of the metal itself. Simply put, all drives of a certain degree through the process began manufacturing in the same way, but a subsequent inspection determined the level of quality that met the disk before being sent out of use. Before starting his spiral course, everything must be pre-set and double-checked from the visual selection and the flatness of the blank disc, the status of the sapphire needle cutting chip suction and all connections and audio settings. An appropriate blank recording disc size is selected ... usually 14 "in diameter to a size of 12" final disc. Once it is launched a cutting stylus can not be stopped without ruining the disk! A trial court silence slot is done outside the diameter of the finished disc. This is examined under the microscope for correct slot size, and sometimes play back to ensure that the noise level is low enough. Sometimes the discs are rejected at this stage, even cutting a pencil could be changed before everything is ready to begin the actual recording.

At this point, the vacuum pump is started, tape players are cued to the beginning of the recording, the group of rotary cutting stock and now the pen is carefully reduced to the disk surface. First, the rapid onset initiative spiral is cut, the tape playback starts once or twice after the spiral has stopped and the audio feed of the disk recorder is enabled. Depth of cut is periodically checked through a microscope, and of course the volume levels should be noted, though automatic variable pitch protects against most cases of indiscriminate felling of adjacent slots. The running time should be checked at the 1 / 4, 1 / 2 and 3 / 4 step to ensure that the disc reaches the desired final point needed for the standardization of the finished product. At the end of registration, after two revolutions in black, the final spiral lead-out groove is made by the acceleration of the screw cutting lathe, either automatically or manually, followed by a lock slot.

In the early days, an eccentric lock slot was added in a special machine designed for this purpose. The teacher is now done and visually examined closely by the failure ... Once the master is not played. to move, teachers are screwed into holes in the center of a complicated picture of separations to keep the current interface, the lacquer is very delicate and easily scratched.

There are minor differences between records, but the most obvious of size and speed of 7 "45 rpm to 12" 33 rpm. The biggest differences, however, are in the slot sizes. Groove thick 16 "radio transcriptions using a groove slightly narrower and more compact than the average 78" standard "but is played at 33 rpm. The channel used for LP's and 45's is even smaller, much tighter. Problems with LP groove precision are higher than with the major groove of age, and a while after their first LP in 1948 it was reported that industry-wide small groove cut was almost impossible. After months of experiencing the cut small indentations became less problems and more problems in this area that the broader process of groove. With minor adjustments to the pen size and depth of cut any type of record could be reduced by the same team. Production of a metal press that fact is recorded in the mold of shellac or vinyl is a multi-coating process.

Depositing metal to metal by an electric current that transfers metal through a coating solution directly to the actual surface is silver. In this record-making point is surrounded by tanks. Rows and rows of containers filled with liquids of various colors, some steam, pouring on some, like things are swished through the deep. To make an impression of real metal or lacquer must flow into the metal and let it harden or a cold plate. The first process is obviously impossible (lacquer is a soft, highly flammable plastic!) Some kind of coating is the only answer. But how the metal plate in a non-metal? A number of methods have been used. The oldest, when master records were cut in wax blocks, was to apply a very thin layer of graphite, a form of carbon, known as the tip of the pen, which conducts electricity. For this coating, thin enough to not disturb the form of improperly record groove, a metal plate could in fact that would form the grooves of record. When enough metal had been supported in the lining, it was an easy matter to strip the wax and graphite, leaving a metal mold. Three ways are used to obtain the first microscopic layer of metal in lacquer. Silver spray is the newest and most delicate and even the bathroom of silver leaf is still used, similar in chemical composition, but takes longer and is less accurate. Varnishes are treated differently, to give metal coatings at first only a molecule or so thick.

The most dazzling to watch involves silver nitrate and a simple pistol. The lacquer surface is "material" to be dipped in a tin chloride solution is washed in a spray of water, leaving a very thin layer. Silver nitrate solution is sprayed on the disc and the black becomes a silver mirror in seconds. Silver has been deposited in a very thin layer of chemicals (replacement) action, the stannous chloride acting as a catalyst to promote the process. The new silver disc is washed and moved to their next treatment. The next goal is to build a solid metal bracket on the shield of fine silver. This can be confusing, since such support "is actually being deposited on the front of the original disc. Remember that we are making a negative mold, the surface of the silver present in direct contact with the surface of lacquer and back to us we look at the record. We look forward in silver on the back, and we're going to add more metal to the rear in order to harden it. The original record will eventually be eliminated, leaving the other side of the silver, the front side down, as the mold. The start of the accumulation of metal music support, a layer of copper fine particle size and delicate or sometimes nickel gradually set in the silver surface just experienced. It is fine grained in order not to disturb the small groove patterns and maintain them accurately in place.

After this, a metal grain sizes can be stacked, but in some plants, another layer of fine grain before "wrap" is added first. The coating thickness is desirable lot faster, because in the fine grain slow before high-speed boards, it can take weeks to create a layer of metal strong enough. One company used special anodes rotating disk that swish around near the surface of the metal disc and do the job to required thickness plates within hours. Other systems use much slower than usual the ballast tanks with the movement of weapons to the content on crops. Enough metal is put on the back of the silver surface to support rigidly. and with a quick stroke of a special hammer with a toss of the insertion tool, the silver around the copper mold is released from the lacquer, and have a negative impact on the metal, the back or down the surface of the silver mirror-image slots original. The paint is often damaged in this process of separation and can not be used again, so the new metal negative "matrix", is now the only way that the existing slots. Being a negative, the grooves are sharp ridges with flat valleys between. This negative or metal "matrix" can now be used to suppress the actual records! Since it is now the only existing copy of the original shellac disc, in most cases is used to produce a "mother", a positive metal disc that can actually be played for testing purposes. The game is not the paper for this mother and instead, the mother undergoes another operation as much as the first coating, which ends in another negative metal is the desired "Stamper". Because the mother, unlike the original brittle lacquer, is made of metal, can be re-plated many times, producing negative after negative in metal, all identical to the first.

We now have a source of negative offspring stampers, each of which can push as many as a thousand finishing your current files. Several mothers can be made from the original parent metal so multiple identical mothers can be sent to pressing plants or other countries for their production needs, and enormous quantities of records can occur very quickly if is necessary, all with exactly the same level of quality of presswork release in the country of origin or the plant. The first step in preparing for the creation of the mother is to remove the silver which now contains the path of direct printing .. Removing the silver layer is necessary as quickly rust or corrode in the air. Fortunately, it is a thin molecule, and the harder underlying metal has virtually the same as the original sharp image. A rumble or two of chromic acid takes silver away faster than it was deposited by spraying in the first place. With the image silver, but still groove "metallic" in the negative matrix, the entire coating process is repeated to re-create a new image. Of the plates, the separation solution is applied to the surface, so that, although the sheet metal on metal, can be stripped later, otherwise the whole thing would become a useless lump of metal solid. Next, a tough but ultra-thin chrome plated surface should read and the hole in the middle, the back of drawing, which must be rectified to the right thickness to accommodate the press and the outer edge that must be trimmed to size. The rear surface is machined in a turning operation in accuracy chisel scraping a spiral path from the outside of the back, right into the interior, shave all the irregularities, leaving a bright mirror backplane. The jagged edges, then go to the stuffing machine centered. As soon as the teacher has its place, is lost. Another blow knocks out a larger area, usually a couple of inches in circumference than half to fit the center of the press. But the disc position is exactly determined by the small hole, so that essential information is held, the last hole in the record to be made in the current pressing upon it.

After the previous steps that occur between the original recording and the final negative metal stamper disk comes the final operation of making the actual record. The basic structure of the press is precisely what is needed for record making ... two similar molds, both heated, mounted face to face with a hinge at the back so that the machine is opened in front of you. Extend these two molds to record the size, holding two registration drives Stamper, one below and one above (by the subject in their schools and around the edges), and has the beginning of a record press behind every Stamper comes a sudden heat, super-heated steam at three hundred degrees, then quick cooling by cold water, all of which must be controlled by opening and closing appropriate valves - and automatically, since no human operator could maintain the desired cycle exact heat and cold that produces the perfect record. Registration for easier and more common is the solid disc, single material all the way through, although more complex records, such as disk-old Columbia rolled, go through the same presses. Record and label are united in pressing. The operator of a pressing machine has beside him a hot tray "in which a dozen are rectangular blocks of material, (shellac or vinyl) about half of the area and two or three times the thickness of the minutes final. The biscuits are softened in hot plate until the consistency of a work-soaked fried mashed only furniture in one piece, and nothing more. With the press open, first label, then a cookie, and then a label is placed in the press, and the top floor. The automated system takes over quietly, water vapor is heated and flows of plastic material in each small slot at the moment is replaced by water, and registration is immediately hardened. You get up, and the next is ready to go

After leaving the hot press fresh record has its ragged edge neatly trimmed by a circular cutting device that went for inspection. Records are rejected by visual inspection and checks of actual play. A significant number are rejected - large containers of rejects, returns and expected cuts to feed the complex machinery that reduces the masses of the disks unsatisfactory pieces and then powder for recycling in most records. Visual inspection is performed by workers who look closely at every disk that comes to them on conveyor belts, separating the rejects. The complementary set out a record-high sample occasionally catches more bugs that have been developed in a Stamper before it is pressed too many bad discs.