Notching is a metal-cutting process used on sheet-metal or thin bar-stock, sometimes on angle sections or tube. A shearing or punching process is used in a press, so as to cut vertically down and perpendicular to the surface, working from the edge of a work-piece. Sometimes the goal is merely the notch itself, but usually this is a precursor to some other process: such as bending a corner in sheet or joining two tubes at a tee joint, notching one to fit closely to the other.
Notching is a low-cost process, particularly for its low tooling costs with a small range of standard punches. The capital cost of the punch press can be expensive though, so small fabrication shops often out-source their notching work to a press shop or notching specialist. Notching of large or heavy sections, particularly for large tube fabrication or HVAC, is increasingly carried out by plasma-cutting rather than punch tools. The first punch & die type tool for notching tube & pipe was invented in Chicago by Julius Vogel, who was issued a US patent in 1938. [1]
The accuracy of punch notching is good, depending on the care with which it's carried out. For manual folding work, prior notching can often improve resultant accuracy of the folding itself.
The speed of notching is usually limited by manual handling when loading the workpieces into the press. Pieces some feet long may be manually loaded into a single-stroke press. Smaller pieces are still generally hand-fed, limiting speeds to perhaps 100 strokes / minute.
Almost any workable metal can be notched. It's particularly suitable where the metal is otherwise awkward to drill, such as stainless steels, titanium or previously heat-treated aluminium alloys. It is an operation of removing a small part of metal sheet of desired shape from edge of metal sheet
Tube notching is commonly performed before joining light-gauge tubes to make a tee or similar joint, as by welding. Either one or both tubes may be notched before assembly. A familiar example of tube notching is in the manufacture of bicycle frames.
End notching works the end of the tube, such as a semicircular concavity to make the base of a tee, or a convex vee to fit into a mitre.
Side notching (also called offset notching) works the side of a tube with a vee notch for bending, semicircular or vee notches for tee joint.
Tube being hollow, it's not practical to use a simple punch operation to notch it, as it would be squashed. Although punching is possible, it requires support mandrels and awkward handling. Where tube is worked with a punch press other than for side notching, this is generally described as slotting.
Tube notching for fabrication of circular tube is thus most commonly done with a rotary hole saw in which a hole saw of the diameter of the tube being attached to is fed into the stock to be notched at a semi-perpendicular angle. This produces a semi-circular notch. Rather than using large presses, such saw notching may only require a simple jig, also making it suitable for on-site working. [2] [3]
A much more accurate way of notching the end of tube stock is to use a specially made milling cutter called an end mill. The stock to be notched is clamped into a vise and can then be fed slowly and accurately into a rotating, hardened metal, end mill. The equipment required for this method is considerably more expensive than the hole saw method and does not lend well to the same portability of the hole saw method as the machine is usually bolted to the floor for stability and safety reasons. This method of end notching is much faster and thus greatly minimizes the chance of damaging the stock either by warping due to heat build up or by squashing as can still happen with a hole saw. [4]
Notching in thin-wall tube may also be carried out by abrasive tools, reducing some of the risk of damage from a hole saw snatching. This also allows more complex shapes to be performed, such as vee notches. [3] In some cases, a helical end mill cutter may be used. [3]
Computer numerical control (CNC) notching is enabling designers to work with more complex geometries.
Vee notches in tube, particularly square tube, may be cut so deep as to cut almost through the tube: three sides of a square tube. This then allows torner[ check spelling ], usually finished by welding.
On a smaller scale for jewellery making, this operation is performed by hand-filing precious-metal strip before bending and soldering to make box frames or stone mounts.
A chisel is a wedged hand tool with a characteristically shaped cutting edge on the end of its blade, for carving or cutting a hard material. The tool can be used by hand, struck with a mallet, or applied with mechanical power. The handle and blade of some types of chisel are made of metal or wood with a sharp edge in it.
Metalworking is the process of shaping and reshaping metals in order to create useful objects, parts, assemblies, and large scale structures. As a term, it covers a wide and diverse range of processes, skills, and tools for producing objects on every scale: from huge ships, buildings, and bridges, down to precise engine parts and delicate jewelry.
A die is a specialized machine tool used in manufacturing industries to cut and/or form material to a desired shape or profile. Stamping dies are used with a press, as opposed to drawing dies and casting dies which are not. Like molds, dies are generally customized to the item they are used to create.
In machining, numerical control, also called computer numerical control (CNC), is the automated control of tools by means of a computer. It is used to operate tools such as drills, lathes, mills, grinders, routers and 3D printers. CNC transforms a piece of material into a specified shape by following coded programmed instructions and without a manual operator directly controlling the machining operation.
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A grinding machine, often shortened to grinder, is any of various power tools or machine tools used for grinding. It is a type of material removal using an abrasive wheel as the cutting tool. Each grain of abrasive on the wheel's surface cuts a small chip from the workpiece via shear deformation.
Sheet metal is metal formed into thin, flat pieces, usually by an industrial process.
An Ironworker is a class of machine that can shear, notch, and punch holes in steel plate and profiles. Ironworkers generate force using mechanical advantage or hydraulic systems.
Hydroforming is a means of shaping ductile metals such as aluminium, brass, low alloy steel, and stainless steel into lightweight, structurally stiff and strong pieces. One of the largest applications of cost-effective hydroforming is the automotive industry, which makes use of the complex shapes made possible by hydroforming to produce stronger, lighter, and more rigid unibody structures for vehicles. This technique is particularly popular with the high-end sports car industry and is also frequently employed in the shaping of aluminium tubes for bicycle frames.
Punching is a forming process that uses a punch press to force a tool, called a punch, through the workpiece to create a hole via shearing. Punching is applicable to a wide variety of materials that come in sheet form, including sheet metal, paper, vulcanized fibre and some forms of plastic sheet. The punch often passes through the work into a die. A scrap slug from the hole is deposited into the die in the process. Depending on the material being punched this slug may be recycled and reused or discarded.
Tool and die makers are highly skilled crafters working in the manufacturing industries. Tool and die makers work primarily in toolroom environments—sometimes literally in one room but more often in an environment with flexible, semipermeable boundaries from production work. They are skilled artisans (craftspeople) who typically learn their trade through a combination of academic coursework and with substantial period of on-the-job training that is functionally an apprenticeship. They make jigs, fixtures, dies, molds, machine tools, cutting tools, gauges, and other tools used in manufacturing processes.
A fixture is a work-holding or support device used in the manufacturing industry. Fixtures are used to securely locate and support the work, ensuring that all parts produced using the fixture will maintain conformity and interchangeability. Using a fixture improves the economy of production by allowing smooth operation and quick transition from part to part, reducing the requirement for skilled labor by simplifying how workpieces are mounted, and increasing conformity across a production run.
JD Squared, Inc. is an American manufacturer of tube and pipe benders. Founded in 1982 and based in Johnson City, Tennessee, the company has manufactured fabrication tools since 1982, starting with tube and pipe benders and later expanding to other fabrication tools. JD Squared is a privately owned Florida corporation. Robert Hughes is the owner and Chief Engineer.
A Model maker is a professional Craftsperson who creates a three-dimensional representation of a design or concept. Most products in use and in development today first take form as a model. This "model" may be an exacting duplicate (prototype) of the future design or a simple mock-up of the general shape or concept. Many prototype models are used for testing physical properties of the design, others for usability and marketing studies.
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A disc cutter is a specialised, often hand-held, power tool used for cutting hard materials, ceramic tile, metal, concrete, and stone for example. This tool is very similar to an angle grinder, chop saw, or even a die grinder, with the main difference being the cutting disc itself. This tool is highly efficient at cutting very hard materials, especially when compared to hand tools.
A turret punch or turret press is a type of punch press used for metal forming by punching.