This article needs additional citations for verification .(February 2010) |
The multimachine is an all-purpose open source machine tool that can be built inexpensively by a semi-skilled mechanic with common hand tools, from discarded car and truck parts, using only commonly available hand tools and no electricity. Its size can range from being small enough to fit in a closet to one hundred times that size. The multimachine can accurately perform all the functions of an entire machine shop by itself.
The multimachine was first developed as a personal project by Pat Delaney, then grew into an open source project organized via a Yahoo! group. The 2,600 member support group that has grown up around its creation is made up of engineers, machinists, and experimenters who have proven that the machine works. As an open-source machine tool that can be built cheaply on-site, the Multimachine could have many uses in developing countries. The multimachine group is currently focused on the humanitarian aspects of the multimachine, and on promulgating the concept of the multimachine as a means to create jobs and economic growth in developing countries.
The multimachine first became known to a wider audience as the result of the 2006 Open Source Gift Guide article on the Make magazine website, in which the multimachine was mentioned under the caption "Multimachine - Open Source machine tool". [1]
As a general-purpose machine tool that includes the functions of a milling machine, drill press, and lathe, the multimachine can be used for many projects important for humanitarian and economic development in developing countries:
The design goals of the multimachine were to create an easily built machine tool, made from "junk," that is nonetheless all-purpose and accurate enough for production work. It has been reported to be able to make cuts within a tenth (one ten-thousandth of an inch), which means that in at least some setups it can equal commercial machine tool accuracy.[ citation needed ]
In almost every kind of machining operation, either the work piece or the cutting tool turns. If enough flexibility is built into the parts of a machine tool involved in these functions, the resulting machine can do almost every kind of machining operation that will physically fit on it. The multimachine starts with the concept of 3-in-1 machine tools—basically a combination of metal lathe, mill and drill press—but adds many other functions. It can be a 10-in-1 (or even more) machine tool.
At a high-level, the multimachine is built using vehicle engine blocks combined in a LEGO-like fashion. It utilizes the cylinder bores and engine deck (where the cylinder head would mate to via the head gasket) to provide accurate surfaces. Since cylinder bores are bored exactly parallel to each other and at exact right angles to the cylinder head surface, multimachine accuracy begins at the factory where the engine block was built. In the most common version of the multimachine, one that has a roller bearing spindle, this precision is maintained during construction with simple cylinder re-boring of the #3 cylinder to the size of the roller bearing outside diameter (OD) and re-boring the #1 cylinder to fit the overarm OD. These cylinder-boring operations can be done in almost any engine shop and at low cost. An engine machine shop provides the most inexpensive and accurate machine work commonly done anywhere and guarantees that the spindle and overarm will be perfectly aligned and at an exact right angle to the face (head surface) of the main engine block that serves as the base of the machine. Use a piece of pipe made to fit the inner diameter of the bearings as the spindle. A three-bearing spindle is used because the "main" spindle bearings just "float" in the cylinder bore so that the third bearing is needed to "locate" the spindle, act as a thrust bearing, and support the heavy pulley. The multimachine uses a unique way of clamping the engine blocks together that is easily built, easily adjusted, and very accurate. The multimachine makes use of a concrete and steel construction technique that was heavily used in industry during the First World War and resurrected for this project.
A lathe is a machine tool that rotates a workpiece about an axis of rotation to perform various operations such as cutting, sanding, knurling, drilling, deformation, facing, and turning, with tools that are applied to the workpiece to create an object with symmetry about that axis.
A machine tool is a machine for handling or machining metal or other rigid materials, usually by cutting, boring, grinding, shearing, or other forms of deformations. Machine tools employ some sort of tool that does the cutting or shaping. All machine tools have some means of constraining the workpiece and provide a guided movement of the parts of the machine. Thus, the relative movement between the workpiece and the cutting tool is controlled or constrained by the machine to at least some extent, rather than being entirely "offhand" or "freehand". It is a power-driven metal cutting machine which assists in managing the needed relative motion between cutting tool and the job that changes the size and shape of the job material.
A machinist is a tradesperson or trained professional who operates machine tools, and has the ability to set up tools such as milling machines, grinders, lathes, and drilling machines.
The bottom bracket on a bicycle connects the crankset (chainset) to the bicycle and allows the crankset to rotate freely. It contains a spindle to which the crankset attaches, and the bearings that allow the spindle and crankset to rotate. The chainrings and pedals attach to the cranks. Bottom bracket bearings fit inside the bottom bracket shell, which connects the seat tube, down tube and chain stays as part of the bicycle frame.
A reamer is a type of rotary cutting tool used in metalworking. Precision reamers are designed to enlarge the size of a previously formed hole by a small amount but with a high degree of accuracy to leave smooth sides. There are also non-precision reamers which are used for more basic enlargement of holes or for removing burrs. The process of enlarging the hole is called reaming. There are many different types of reamer and they may be designed for use as a hand tool or in a machine tool, such as a milling machine or drill press.
A mandrel, mandril, or arbor is a tapered tool against which material can be forged, pressed, stretched or shaped, or a flanged or tapered or threaded bar that grips a workpiece to be machined in a lathe. A flanged mandrel is a parallel bar of a specific diameter with an integral flange towards one end, and threaded at the opposite end. Work is gripped between the flange and a nut on the thread. A tapered mandrel has a taper of approximately 0.005 inches per foot and is designed to hold work by being driven into an accurate hole on the work, gripping the work by friction. A threaded mandrel may have a male or female thread, and work which has an opposing thread is screwed onto the mandrel.
A collet is a segmented sleeve, band or collar. One of the two radial surfaces of a collet is usually tapered and the other is cylindrical. The term collet commonly refers to a type of chuck that uses collets to hold either a workpiece or a tool but has other mechanical applications.
A chuck is a specialized type of clamp used to hold an object with radial symmetry, especially a cylinder. In a drill, a mill and a transmission, a chuck holds the rotating tool; in a lathe, it holds the rotating workpiece.
A machine taper is a system for securing cutting tools or toolholders in the spindle of a machine tool or power tool. A male member of conical form fits into the female socket, which has a matching taper of equal angle.
Turning is a machining process in which a cutting tool, typically a non-rotary tool bit, describes a helix toolpath by moving more or less linearly while the workpiece rotates.
The shank is the end of a drill bit grasped by the chuck of a drill. The cutting edges of the drill bit contact the workpiece, and are connected via the shaft with the shank, which fits into the chuck. In many cases a general-purpose arrangement is used, such as a bit with cylindrical shaft and shank in a three-jaw chuck which grips a cylindrical shank tightly. Different shank and chuck combination can deliver improved performance, such as allowing higher torque, greater centering accuracy, or moving the bit independently of the chuck, with a hammer action.
A lathe center, often shortened to center, is a tool that has been ground to a point to accurately position a workpiece on an axis. They usually have an included angle of 60°, but in heavy machining situations an angle of 75° is used.
In machining, a metal lathe or metalworking lathe is a large class of lathes designed for precisely machining relatively hard materials. They were originally designed to machine metals; however, with the advent of plastics and other materials, and with their inherent versatility, they are used in a wide range of applications, and a broad range of materials. In machining jargon, where the larger context is already understood, they are usually simply called lathes, or else referred to by more-specific subtype names. These rigid machine tools remove material from a rotating workpiece via the movements of various cutting tools, such as tool bits and drill bits.
In machining, boring is the process of enlarging a hole that has already been drilled by means of a single-point cutting tool, such as in boring a gun barrel or an engine cylinder. Boring is used to achieve greater accuracy of the diameter of a hole, and can be used to cut a tapered hole. Boring can be viewed as the internal-diameter counterpart to turning, which cuts external diameters.
In a piston engine, the bore is the diameter of each cylinder.
The cylindrical grinder is a type of grinding machine used to shape the outside of an object. The cylindrical grinder can work on a variety of shapes, however the object must have a central axis of rotation. This includes but is not limited to such shapes as a cylinder, an ellipse, a cam, or a crankshaft.
The Van Norman Machine Tool Company was an American machine tool builder from late in the 19th century until the mid-1980s. The company was based in Springfield, Massachusetts, USA. Its main areas of focus were milling machines and grinding machines. The company was acquired by Universal American Corporation during the early 1960s. Universal American later merged with Gulf and Western Industries.
In machine tools, a spindle is a rotating axis of the machine, which often has a shaft at its heart. The shaft itself is called a spindle, but also, in shop-floor practice, the word often is used metonymically to refer to the entire rotary unit, including not only the shaft itself, but its bearings and anything attached to it. Spindles are electrically or pneumatically powered and come in various sizes. They are versatile in terms of material it can work with. Materials that spindles work with include embroidery, foam, glass, wood, etc.
In metalworking and woodworking, an automatic lathe is a lathe with an automatically controlled cutting process. Automatic lathes were first developed in the 1870s and were mechanically controlled. From the advent of NC and CNC in the 1950s, the term automatic lathe has generally been used for only mechanically controlled lathes, although some manufacturers market Swiss-type CNC lathes as 'automatic'.
Milling is the process of machining using rotary cutters to remove material by advancing a cutter into a workpiece. This may be done by varying directions on one or several axes, cutter head speed, and pressure. Milling covers a wide variety of different operations and machines, on scales from small individual parts to large, heavy-duty gang milling operations. It is one of the most commonly used processes for machining custom parts to precise tolerances.