Below, you will find two descriptions of the manufacturing process for vinyl records. The descriptions come courtesy of independent record manufacturers "Music Manufacturing Services" and "Aardvark Record Mastering".

Your master is first transferred to a disc, called a lacquer, which is 14 inches in diameter. To do this we use a cutting lathe. These discs are actually lacquer-coated aluminum and are often referred to as acetates. The lathe has a turntable upon which the lacquer is placed, but instead of a tone arm with a regular stylus, there is an instrument with a diamond stylus that cuts out the groove on the lacquer, under the guidance of a computer. When the disc is ready to be cut and the parameters set, the lathe moves into the proper diameter. For a 12-inch master disc it moves into 11 7/8 inches, drops the head and makes a fast spiral groove (on the outside, to guide the stylus into the playing area). The cutting stylus cuts anything that is completely left side information, although the stylus itself is vertical, at a 45ƒ angle to the left. Anything it sees as right side information is cut at a 45ƒ angle in a plane to the right. Anything it sees as lying in the center of the two speakers is cut completely horizontally. Any sound occurring completely in the right speaker, not appearing in the left speaker, or vice-versa, is called vertical information: the stylus moves in an up and down direction. When the master tape indicates a space, the lathe automatically puts a little spread between the tunes. After getting to the inside diameter and the cutting is finished the machine puts in a spiral and a lock groove, ties it off and lifts the cutting head. It takes maybe 20 minutes per side to set up the parameters on the disc mastering console. It takes running the master once and listening to all the sound on that side. We normally cut a test disc while doing this, which is generally discarded, but we're making adjustments all the way. When the master is complete we microscopically inspect it and ship it to the pressing plant. At the plant, they coat the lacquer with silver (electroplating). When this coating is thick enough it is peeled off to create a 'metal master' which is now a negative image of what was on the lacquer (it has ridges where the grooves go). Several "mothers" are made from the metal master (again by electroplating) which are intermediate masters, and positive images again. The process is repeated once again to form negative discs called "stampers". These stampers, which have refinements like a depression around the edge to make the raised outer rims of the discs, are the "molds" with which the grooves are actually stamped on vinyl (under intense heat and pressure). With this three step process, involving metal masters and mothers, you can make as many discs as possible from a single lacquer, otherwise the tricky process of lacquer-cutting would have to be repeated almost continuously, increasing the likelihood of inconsistency in the finished product. The finished records are then sleeved and boxed ready to be shipped to you.

The following more detailed description of Vinyl Manufacturing or mastering is taken from Aardvark Record Mastering. There web site can be found at http://www.aardvark-mastering.com/proceed.htm.

I. The master disks (one disk for each side of your record) are sent Federal Express to the plater. They must be expressed as they are only good for a few days, then microorganisms start growing in the lacquer of the master's grooves. There is some debate as to how long it takes for the lacquer to deteriorate. The lacquer manufacturers say they should be plated within 72 hours of cutting. The platers are able to get clean plates even when the lacquer is a few weeks old. Either way, I make certain that the plating happens within a week of cutting. I haven't had any problems with this practice. II. Plating: A. The plater coats the master disk with a thin layer of silver. This is then electroplated with nickel to about 15 thousandths of an inch thick. When the metal is separated from the master disk, the metal that was facing the disk now has protruding ridges where the grooves were. This plate is called the FATHER plate. B. The FATHER plate is oxidized, and plated again. The resulting plate when separated becomes a metal duplicate of the master disk with grooves again. This plate is called the MOTHER plate. The MOTHER can be played on a turntable to check for errors in mastering or plating. C. In a two step process, the FATHER plate is converted into a STAMPER, the MOTHER is shelved for future use. D. In a three step process, the MOTHER is oxidized, and plated to make the STAMPER plates. E. One FATHER can produce 10 MOTHERs. One MOTHER can produce 10 STAMPERs. One STAMPER can produce about 1000 vinyl records. Therefore, a two step process can produce a maximum of about 11,000 records before a remastering has to be done, and a three step process can produce up to about 100,000 vinyl records before remastering. I have not seen any independent records go above 10,000 pressings, so I suggest the two step process. F. Advantages of the three step process: 1. More records may be produced without remastering. 2. When silver is used on the master disks, there may be some leftover silver on the FATHER plate that can cause some noise. In the two step process, this silver is removed, however, some may remain. The three step process will not have any residual silver on the STAMPERs. If there is noise caused by silver, a new stamper can be pulled from the MOTHER, and there will be no silver residue. 3. In the cutting process, the edge of the groove forms a small ridge called a horn. This horn can catch the vinyl in the record press causing "non-fill" where the vinyl doesn't quite fill between the grooves, and will cause a crackling sound. Polishing the MOTHER plate will remove this ridge, and the vinyl will flow properly between the grooves. I have had this problem less than 10 times in the 11 years I have been mastering, and a new plate always solved this. 4. I always suggest the two step process because of the savings over the three step process, about $50, and if problems arise, the MOTHER can be used to determine if there was a problem in plating or mastering. G. Plates are usually good for about a year. It is wise to have your STAMPERs returned from the pressing plant with your record order as they will cash in the scrap nickel after they store them for about 6 months. The MOTHERs are usually held for a year at most platers, but they can be returned to you. It's best to wait until you have the records completed in case there is any problem with the pressing plant. III. Labels are printed from typesets or camera ready artwork. Usually they are one color ink on a contrasting paper such as red ink on white paper, silver ink on black paper, black ink on pink paper. The inks are to be the darker color except when using silver ink. Seven inch records use 3-5/8 inch labels with either a 9/32 inch or a 1-1/2 inch center hole. Twelve inch records use a 4 inch label with a 9/32 inch hole, and ten inch records use either 3-5/8, or 4 inch labels with a 9/32 inch hole. 78s use a 3 inch label, as do some odd sized records. Camera ready art should be black on white with specifications of what color inks are to be used where the black is, and what color paper on which to print. IV. 12 inch jackets are printed at a jacket manufacture. They usually need printer's film. This differs from photography film as the negatives used for printing are actual size, and there is no grey scale in the photographs. To do photos, a process called halftones is used where the photo is converted into small dots of varying size. This gives the illusion of greys. Color photos are converted into 4 layers of printer's film, each layer appearing black and white. Each layer is used to print one of the 4 "process" colors of yellow, magenta, cyan and black. Combinations of these 4 colors in varying degrees will produce any nonmetallic color in the final printing. The process for black and white film is called engraving, and for color it is called color separations. Some jacket manufacturers have on-site or subcontracted film engravers, most want the film. V. Test Pressings are run using the stampers that will be used for the final pressings. These pressings are samples of the final pressings. They usually have plain labels. Sometimes the seven inch records will have the wrong size hole. This is because they either punch the 1-1/2 inch hole or not depending on what plant you use. Tests must be approved before the plant will go ahead and run the records. Check the following: A. Noise, pops occurring in the same place on every test pressing. B. Record Numbers, be sure the record number written in the "wax" for each side is correct with the "A" side being the "A" songs. C. Skipping, again on each copy of the tests. D. If there are problems, call me. I cover excessive noise, and skipping, but I will only assume liability for remastering, and plating if I handled the plating. I may request that at least one copy of the tests be sent to me. VI. Pressing: A. The pressing plant needs the stampers from the plater, and the labels from the printer before they can start. B. The vinyl is loaded as a glob between the labels, then the mess is squashed in the press between the two stampers at about 300 degrees Fahrenheit, and 100 tons of pressure for about 20 to 30 seconds. C. The excess vinyl is trimmed off the edge of the record, and the record is stacked for cooling. D. The final pressing is then loaded into the paper sleeve and jacket if applicable. E. The completed product is then shipped to you.