Wire Wrap Overview Manual Wire Wrap Semiautomated Wire Wrap

The electronic parts plug into sockets. The sockets are glued with cyanoacrylate (or silicone glue) to thin plates of glass-fiber-reinforced epoxy.

The sockets have square posts. The usual posts are 0.017 inches (430 micrometres) square, 1 inch (25 mm) high, and spaced at 0.1 inch (2.5 mm) intervals. Premium posts are hard-drawn beryllium-copper alloy plated with a 0.0025 in (64 micrometres) of gold to prevent corrosion. Less-expensive posts are bronze with tin plating.

30 gauge silver-plated soft copperCopper is a chemical element in the periodic table that has the symbol Cu and atomic number 29. Notable characteristics Copper is a reddish-coloured metal, with a high electrical and thermal conductivity (among pure metals at room temperature, only silver wire is insulated with a fluorocarbonFluorocarbons are carbon- fluorine compounds that often contain other elements such as hydrogen, chlorine, or bromine. Common fluorocarbons include chlorofluorocarbons and related compounds (also known as ozone depleting substances including hydrochlorofl that does not emit dangerous gases when heated. The most common insulation is " kynarKynar is the Pennwalt trade name for polyvinylidene fluoride, a fluorocarbon material typically used as insulation for wire-wrap wire. Kynar insulation is very thin and fragile, and is generally used in electronics work where heat and abrasion are not an."

The 30 AWG Kynar is cut into standard lengths, and then stripped of insulation for one inch on each end.

A special toolThis page discusses common devices known as "tools". For the band, see Tool (band). For other meanings, see Tool (disambiguation). A tool is, among other things, a device that provides a mechanical or mental advantage in accomplishing a task. Most tools e called a "wire wrap tool" has two holes. The wire and a quarter inch (6 mm) of insulated wire are placed in a hole near the edge of the tool. The hole in the center of the tool is placed over the post.

The tool is rapidly twisted. The result is that 1.5 to 2 turns of insulated wire are wrapped around the post, and atop that, 7 to 9 turns of bare wire are wrapped around the post. The post has room for three such connections, although usually only two are needed. This permits manual wire-wrapping to be used for repairs.

The turn and a half of insulated wire help keep the wire from fatiguing where it meets the post.

Above the turn of insulated wire, the bare wire wraps around the post. The corners of the post bite in with pressures of tons per square inch (MPa). This forces all the gases out of the area between the wire's silver plate and the post's gold or tin corners. Further, with 28 such connections (seven turns on a four-cornered post), a very reliable connection exists between the wire and the post.

2 Manual wire wrap

Manual wire wrap tool resemble small pens. They are convenient for repair. Wirewrap is the one of the most repairable systems for assembling complex elecronics. Posts can be rewrapped up to ten times without appreciable wear, as long as new wire is used each time.

3 Semiautomated wire wrap

Semiautomated wire-wrap systems place "wire-wrap guns" on arms moved in two dimensions by computer-controlled motors. The guns are manually pulled down, and the trigger pressed to make a wrap. The wires are inserted into the gun manually. This system lets the operator place wires without worrying about whether they are on the right pin. The computer puts the gun over the right pin.

4 Automated wire wrapping

Automated wire-wrap machines have two wrap-heads, and two claws to route the wire. On each wire, the two wrap heads come together above a place between the two pins of the next wire. One end is stripped and inserted into the passive head, which grips the wire. The wire is unreeled from the active head. The claws pull the wire to the correct routing. Then the other end of the wire is stripped and clamped in the active head. Both heads and both claws descend, routing the wire and wrapping both pins at once. Automated machines can place a wire every second, almost five times as fast as the most skilled semiautomated wire-wrap operators.

In commercial wire-wrapping, computer programA computer program (often simply called a program is an example of computer software that prescribes the actions (" computations") that are to be carried out by a computer. Most programs consist of a loadable set of instructions which determines how the cs are used to optimize the order in which wires are placed. The programs generate a list of wires, and then put numbers in the list. The list is then sorted by the numbers.

For example, wires are "top & bottomed." That is, wires alternate between high and low as they connect a series of pins. This lets a repair or modification occur with the removal of at most three wires.

Another optimization is that long wires are placed first within a level, so that shorter wires will hold longer wires down. This reduces vibration of the longer wires, making the board more rugged in a vibrating environment such as a vehicle.

Placing all the wires of a certain size, makes it easier for a manual or semiautomated wire-wrapping machine to use precut wire. This especially speeds up manual wrapping.

Another optimization is that within each size of wire, the computer selects the next wire so that the wrap head moves to the nearest pin.

Finally, the direction of placing a wire can be optimized for right-handed wire-wrap people, so that wires are placed from right to left. In a semi-automated wire-wrap system, this means that the wrap head moves away from the user's hand when placing a wire. The user can then use their strong hand and eye to route the wire.

Semiautomated wirewrapping is unique among prototyping systems because it can place twisted pairs, permitting complex high frequency computer and radar systems.

5 See also

Point-to-point constructionPoint-to-point construction is the way most electronics were constructed before 1950s. Point-to-point construction is still used to construct prototype equipment with few or heavy components. The crucial invention was soldering. In soldering, an alloy of
PCB layout guidelinesMany practical circuits can be laid out easily if the lumped element model holds for the particular circuit. In radio especially, we cannot make this assumption and we must minimize parasitic effects due to layout of components, or take them into account
veroboardVeroboard is the trademark name of the electronics prototyping board manufactured by the Vero Electronics company. Among electronics hobbyists and professionals, the name Veroboard is synonymous with similar prototyping board, also called stripboard, made

6 External links

Pictures, specifications, and the technology of wire wrapping

6.1 Tool & supply manufacturers

Wire wrap jewellery is a type of jewellery design and method of hand jewellery fabrication. Electronics

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1 Overview