An automatic or manual device used to cut and trim paper and other substrates. Guillotine cutters are available in a variety of configurations and with varying degrees of automation and computer control, but all essentially comprise the following: a flat bed made of metal on which the material to be cut is placed; a long, heavy steel or steel-carbide knife which is mounted to a bar located near the front of the machine, which is either mechanically or electronically brought down through the material to be cut; a cutting stick imbedded in the bed directly beneath the knife, so as to prevent blade damage; a cutter clamp, a metal bar or plate that is lowered onto the stack of material to be cut, compressing the air out of it and holding it firmly in place while the knife cuts it; and stationary side guides and a moveable back gauge, which hold the stack of sheets squarely in place in the desired position on the bed to cut the sheets to the desired size. On some cutters, a split gauge is used, which is divided into two or more segments allowing for more than one edge of a stack to be cut without needing the back gauge setting to be changed between cuts.
Of particular concern with the use of guillotine cutters is the angle at which the knife contacts the sheets. Average weight papers—such as writing paper or common printing papers—are accurately cut with a knife angle of 22º, but thinner or heavier papers may require smaller or larger angles, respectively. The clamp pressure also may be too high or too low, depending upon stock thickness. Experience and experimentation are the best indicators for these materials.
Although the earliest guillotine cutters were operated simply by pulling a large metal handle to bring the knife down through the stock, a variety of high-tech improvements have made the cutter a remarkably efficient and computerized device. On many models, desired sizes can be programmed into a computer, and the back guide automatically moved to the correct position between cuts. This has the desired effect of eliminating the need for the operator to put his hands under the knife to move the stock into position.
There are many electronic and mechanical accessories to cutters which have not only improved safety but have also increased production capacity. These include low-pressure air tables, which have improved the feeding and flow of materials to the cutter; cut-line indicators use a thin line of light to indicate on the stock where a cut will be made, eliminating the need to tentatively lower the knife to the stock to ensure that an image area will not be cut; gripper-loading systems automatically remove stock from joggers and feed it directly to the rear of the cutter bed while tilting transfer tables have enhanced the ability to automatically feed large-size sheets. Cutting information for several jobs can be programmed into a computer off-line, and sent to the cutter via modem or by inserting a diskette, eliminating downtime between jobs. Lifting tables utilize sensors to detect pile height and accurately load it into position on the cutter, and post-cutting vertical storage systems automatically stack cut piles, often utilizing a jogger to ensure that stacks are kept square and straight.
(See also Cutting and Trimming and Binding and Finishing.)