Factors That Affect the Speed of a Paper Cutter

During the design process of a new paper cutter, it is important to consider the factors that affect the speed of the machine. These include the speed of the Spindle, Feed rate, Idle time and Chain tension.

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Spindle speed

Increasing the spindle speed of a paper cutter has been a longtime goal of many in the industry. With the help of new machine and spindle designs, high-speed machining has become an affordable option for smaller parts.

A new twist on the old standby, the VFD spindle, offers low-cost, high-performance spindles that are ideal for small part production. The most common applications for the VFD spindle are producing paper and packaging components, such as labels, stickers and paper tapes. The spindle is typically accompanied by a collet and a tool holder. The first step to setting up the VFD spindle is to raise the tool holder to free spinning position. It is also helpful to set the spindle to a slow speed first, in order to prevent damage from the spindle moving at the wrong speed.

Feed rate

Increasing feed rate increases cutting power. However, when the rate of feed is too fast, the cutter can dull faster. Similarly, when the rate of feed is too slow, the cutter will slice off more material than needed. This can result in too large a chip and too small a surface.

The optimum feed rate for woodworking depends on the number of teeth on the cutter and the desired amount of material per tooth. This is usually determined by trial and error when power feeding or by feel when hand feeding.

The mathematical relationship between the cutting force F and the feed rate V is useful in adjusting the feed rate in medium machining and finishing. The feed rate is measured in units of distance per revolution for turning, and units of distance per time for milling.

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Chain tension

Various parts of a conveyor system may be repositioned, which will result in changes in chain tension. For example, when a loaded conveyor is started, many components may be repositioned, including the chain, which could cause a change in chain tension.

It is important to ensure that the cutting machine paper chain is properly tensioned. If it is too loose, it can whip backwards towards the user. It can also derail the saw bar. A proper tension will hold the chain against the bottom of the bar, preventing damage to the saw as it spins around the bar.

To determine the effect of chain tension on cutting efficiency, force values were obtained for a variety of cutting conditions. These force values were calculated from the number of sprocket teeth on the chain. The magnitude of these forces was measured by a linear bearing system paired with a S-beam load cell.

Backgauge squareness

Keeping the backgauge square is a critical step to cutting sheets accurately. This is particularly true if the paper cutter is used to cut parallelograms, which can be difficult to align into a corner. If the stack of sheets is not square, it will not cut properly, and the operator may also notice inaccuracies later on in the process.

Typical industrial paper cutters use clamps and fixed gauges to hold sheets in place. This technique allows for quick adjustments during the process, but the operator must be sure to follow the manufacturer's procedures. Otherwise, the sheets may be cut incorrectly, resulting in distortion of the stack and an error in the printed material.

Newer machines have computer displays, which enable the operator to check for the correct backgauge position. However, each manufacturer has its own way of adjusting the gauge. This is usually done at practically every cutting cycle.

Idle time

Basically, the idle time of a paper cutter machine is the amount of time spent by the cutter while it is not performing any operation. It includes the time for changing tools, adjusting machine settings, loading and unloading jobs, etc. It is also called as non-productive time. This time may vary depending on the feed rate and cutting velocity.

The cut speed is a factor affecting the idle time of a paper cutter. It is measured by notches per minute or seconds. It depends on various factors like the material being cut, the type of operation, and the speed of the cutter. This will determine the total production time. It is calculated by dividing the total cut length by the feed rate. In conventional machining, the cutter may require several tool changes. This will lower the life of the cutting tools.