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Plasma Cutting – Precision and Accuracy

A machine is accurate when it does exactly what you want and it is precise when it does exactly what you want over and over again. I am going to talk about CNC (computer numeric control) plasma cutters here because with hand held plasma cutting equipment it is your skill and talent that determines precision and accuracy. With a machine, it is a variety of factors that do not included skill or talent.

Generally, mechanical machining processes lend themselves to easily assign standard tolerance, but that is not so for Plasma Cutting equipment. The actual machine (the cutting table, motors, rails, CNC, and bridge) actually have tolerances that far exceed the tolerances of the plasma cutting process itself. There are many different factors that can influence the precision and accuracy, collectively referred to as the quality, of the plasma cut including: the unit’s power settings, the type of consumables, the gases used, type of material, characteristics of the material being cut, gauge (thickness) of the material, the layout of the parts on the plate.

Other factors affecting the cut quality include construction and condition of the rail system, the type of CNC unit and PC used, the sizing of the motors relative to the gear box, the drive systems used, etc. As you can see there are lots of details that can affect the cutting quality of plasma cutting system. So when you are buying a CNC plasma cutter it is best to ask the manufacturer to provide you with cut samples made using the machine and plasma cutter combination that you are interested in. Ask that the samples closely resemble what you will be cutting with the machine. That way you will have an idea of the quality of the cut with different set ups. If the quality is not up to snuff then keep looking. You will be dropping a pretty penny on plasma cutting equipment, so make sure it does exactly what you need with accuracy and precision.

Technical Control Room Furniture Design and Employee Performance

Technical control room furniture is designed to make the user more comfortable and more effective during long shifts often under demanding circumstances. The design of the furniture goes to the shape and size of space, equipment requirements, ergonomics, furniture layout, lighting, equipment type and accessibility. The success of the furniture design is measured by employee effectiveness, attitude, absenteeism and job turnover. Unhappy employees don’t stay very long. Other factors related to employee performance are job descriptions, evaluations, office rules, environmental control and relationships with management and coworkers.

Factors considered when designing technical control room furniture

When designing technical control room furniture, it’s important to consider the levels of physical and mental stress under which the user will be working. This will allow you to design the furniture in a way that maximizes employee effectiveness.

1. Shift Patterns

Since many control rooms function for 24 hours without interruption, the furniture should be 24×7 rated and purchased from an experienced manufacturer that specializes in intensive-use furniture. This customized furniture should allow users with varying physical characteristics to perform efficiently regardless of the situation including those disabled members of the staff.

2. Situation Awareness

Furniture designed for critical operations should not be too comfortable for obvious reasons. Although furniture should be designed for comfort, control rooms are not “living rooms”. Conversely, when workers are not comfortable, then productivity drops off and there’s the potential for critical errors. So actually, it’s a balancing act between the two extremes.

3. Emergencies

An employee’s duties during a normal working day and during emergencies can be demonstrably different, or at least be refocused on other activities for extended periods driven by the requirements of the incident. There’s the need to solve problems during emergencies as well as gather additional staff, coordinate activities, schedule employee overtime; all of which drive stress levels by all involved. Technical furniture should be adaptable and designed to reinforce the operator’s activities during these events.

4. Environmental Conditions

The environmental conditions within a control room play an important role. Aside from the design and performance of the furniture, the space should be adequately lit and have adequate temperature control including personalized control at desktop level. Appliances installed in the desktop that accept centralized connections for data and power simplifies cable management. These appliances also provide personalized fan cooling and heating, and control of task lighting and motorized desktop adjustability all with the touch of a button.

The most important consideration when designing furniture is the human factor. It’s all about the professionals that inhabit the control room on a continual basis potentially dealing with crisis after crisis. If the operators are not comfortable, they aren’t productive. If the furniture does not lend itself to efficient operation of the equipment in and on the furniture, then the operator can be ineffective and likely to commit errors especially during emergency situations. Considering that control rooms often function round-the-clock, they need to be furnished to accommodate the requirements of a continuous flow of employees during and after shift changes. Working with an experienced control room furniture designer will help you bridge the gap between the appropriate furniture design, employee needs, the work they do and the space they inhabit.

The Difference Between Acoustic and Electric Guitar

The differences between acoustic and electric guitars are myriad. In addition to one requiring electricity to be heard and the other one not requiring anything but a skilled set of hands, the way in which each one is made and the uses of each one stand in stark contrast to one another.

An acoustic guitar is a hollow-bodied, six-stringed instrument. The sound produced by an acoustic guitar comes from the vibrations created by a note or notes being plucked or strummed on the strings and echoing throughout the hollow inside of the instrument’s body. Steel-stringed acoustic guitars are made of wood, and the tops of acoustic guitars are usually made from spruce, although some are made from rosewood or maple. Other acoustic guitars are nylon-stringed, or classical, guitars. These are usually smaller, and the strings are tied to the bridge in a knot rather than held in with a peg like on steel-stringed acoustic bridges. Classical guitars are used in a variety of musical applications from jazz, traditional Latin folk music, to, of course, classical guitar compositions. Classical guitars are most often played with the fingers, but a plectrum may be used to play either steel-stringed or classical acoustic guitars. Blues, rock, and most Western folk music is played on steel-stringed acoustic guitars. While acoustics are traditionally played without the need for electric amplification, acoustic-electric models–acoustic guitars equipped with electric pickups–are quite popular for acoustic artists whose professional needs call for amplification.

Electric guitars, on the other hand, can be hollow-bodied or solid. In the twenty-first century, hollow-bodied electric guitars are less commonly-used than solid-body variations, but a number of rock, blues, and jazz musicians still prefer the tones they produce. Hollow-bodied electric guitars usually have f-holes (like a violin or cello) as opposed to the single, large, circular hole in an acoustic guitar body. The first solid-body electric guitar, the famous Les Paul model, was introduced in the 1950s, and since then the solid-body electric guitar has become a staple for guitarists involved in all genres of popular music. Solid-body electrics feature either a bolt-on neck (like the Fender Stratocaster) or a set-in neck (the Les Paul, for example), and can make use of either single-coil pickups for use with clean channel amplification or humbucker pickups for use with distortion. Electric guitars, unlike acoustics, are rarely manufactured with natural finishes. The bodies can be made from a number of different woods, but the most common are alder, ash, or mahogany. The mahogany bodies of most Gibson guitars are credited for the warm tones their guitars produce. There are, however, a limited number of electric guitars that make use of synthetic materials since all the guitar requires to be heard is amplification as opposed to a hollow cage of wood. Even so, the most popular electric guitars are made from wood and are believed to provide superior tonality than those made from anything else.