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Top: Business: Industrial_Goods_and_Services: Casting,_Molding,_Machining: Machine_Shops

The overwhelming majority of Machine Shops concentrate on general machining of metal parts, each serves what is essentially a local market, and, if only as a matter of convenience, seem best indexed in a series of Full_Service subcategories that reflect their individual locations.

However, it seems useful to isolate shops that offer a particularly specialized form of machining, and they are therefore indexed under either this main Machine_Shops category or in readily identifiable categories such as Spinning and Stamping. As will be seen, sites allocated to this main Machine_Shops category are those that focus on less common machine processes as, for example, thread rolling and cold heading.

Electrical Discharge Machining

This category indexes sites of companies involved in electrical discharge machining, a process that removes metal from a workpiece by using a controlled electrical current to cut and create intricate shapes in materials that would be difficult to handle with other machining operations. Some secondary capabilities are often offered by these companies, but the focus is unquestionably upon EDM work -- and needs to be so to warrant inclusion here.

Full Service

With few exceptions, Machine Shops each serve a local market rather than catering to a national (let alone an international) customer base. In turn, most of them concentrate on jobs that can be considered in terms of general rather than specialized machining. In other words, they produce parts by turning, milling, boring, and grinding metal, but they don't often go beyond these processes.

Given this basis -- and recognizing the sheer volume of firms of so similar a nature -- it is considered useful, if only as a matter of convenience, to index Machine Shop sites under a series of subcategories based on location.

Note: Shops that (regardless of what they may call themselves) concentrate on a particular type of machining as opposed to a variety of general operations are, relatively speaking at least, much less numerous -- and in consequence their customers are more widely scattered. Accordingly, sites of this kind are collected -- and retained -- under several appropriate headings such as Grinding, Spinning, and Stamping. In a few cases, too, shops focused on less common machining processes (as, for example, thread rolling and cold heading) are allocated to the main Machine_Shops category.

Additional note: Tool and Die Shops differ from Machine Shops and have a category of their own. Their emphasis is on producing tooling, patterns, dies, fixtures, gages, and parts that involve one form or another of special or sophisticated machining. As with Grinding companies and their like, their numbers aren't too unmanageable, and there is no benefit in breaking them up into location subcategories.

Gear Manufacturing

This category contains sites of companies involved in producing power transmission components. Many of them are fair sized corporations engaged exclusively in gear manufacturing, while others are relatively small machine shops focused on the same kind of product. A few serve a narrow market niche (the French AML firm is an example), but the majority cover a broad range of gear, gearbox, and geared motor requirements in the form of either standard or custom produced items.

Metal Fabricators

This category contains site of job shops and manufacturers that specialize in fabricating metal parts either in a more sophisticated way than by general machining or in a less than usual -- and more than likely advanced and complex -- form. It also includes site of companies that offer a diversified range of capabilities and are difficult to classify under an otherwise narrow heading (e.g. spinning, stamping, etc.).

Note: There is a subtle but important difference between sites in this category and those indexed in the Sheetmetal one. There, the essential emphasis is on working with sheet material that is cut, pressed, bent, and, often enough, also stamped into a required shape. Or, to put it another way, sheetmetal products could be hammered flat, whereas fabricated metal components could never be returned to their original shape.

Precision Cutting

This category covers machine shops that specialize -- or are primarily involved -- in waterjet, plasma, or laser cutting. Where this kind of operation is merely an ancillary (i.e. additional or secondary) part of the business, the firm's site more properly belongs in its appropriate Full_Service/Regional subcategory.

Note: Sites providing or focused on laser marking and engraving services are also appropriate for this category.

Screw Machine Shops

This category contains sites of shops that concentrate on what is generally known as (Swiss) screw products, which are produced -- usually from bar stock -- on a single piece of equipment. In most cases, they are small rather than large and complex as opposed to simple. Moreover, their manufacture can be seen as a "one shot affair," rather than the result of using a succession of machine tools (e.g., lathe, drill, grinder, milling machine, etc.) to produce a part. There are only a few makes of screw machines, but they all incorporate a collection of spindles, each one of which can be set and used to perform a given operation in the path towards the finished product.

Note: As an alternative to what are strictly termed screw machines, some lathes and machining centers have multi-axis capabilities and can either replicate screw machine production or handle parts that fall outside the diameter and/or length capacities of screw machines.

Tool and Die Shops

This category covers sites of shops that are primarily concerned with the design, production, and supply of dies, fixtures, jigs, and other forms of tooling for a variety of end users. As such, while they may also offer machining services -- as a number of them do -- they are focused on the tooling needs of their customers rather than simply on what they require themselves for subcontract orders.

Note: There is an obvious similarity with companies that make patterns, molds, and dies for the casting and plastic industries, as opposed to producing tooling for machining and fabrication customers. However, sites of this nature are concentrated in -- and should be directed to -- the Business/Industries/Manufacturing/Polymers/Machinery_and_Tools/Molding/Mold_Making/ category. If, of course, a Tool and Die Shop serves both kinds of markets (as a few of them do), its site can -- and should -- be indexed in whichever category better reflects its focus.

Trepanning, Gundrilling, Boring

This category contains sites of machine shops -- and there are relatively few of them -- that concentrate on what is perhaps the same idea: the drilling of centered holes through lengths of tubing, and usually long ones at that. Gundrilling, as its name suggests, originated as an operation in the manufacture of firearms, but it now applies to various other deep hole drilling applications. Boring -- in the case of this category at least -- applies to the creation of large diameter rings, invariably with quite thick walls. And trepanning is a process that produces thick walled tubes in such a way that the centre core is retained rather than being drilled away (as, in contrast, it is in gundrilling and boring operations).

Note: Although some shops include one or more of the capabilities covered in this category, their sites need to be focused on them to be listed here. If the business emphasis lies elsewhere, the firm should be indexed in a correspondingly more appropriate category.

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