Читать книгу How Paper Boxes Are Made - Robert F. Salade - Страница 6

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The term “set-up,” applies to paper boxes which are covered with separate lids. Folding boxes do not come under this term for the reason that they are glued together at one side, and remain in flat form until the time when they are used as containers, cut out sections of the sheet then being folded to serve as “lids.” In other words, a folding box is complete in one piece, while a set-up box (a shoe box, for example), is of two parts, the box and the lid.

A set-up box must be cut, creased, folded, stayed and covered before it is complete. The lid also must be cut, creased, folded, stayed and covered.

Various kinds of boxboard are used for the making of plain paper boxes, but the three principal kinds used are called “Chip-board,” “News-board” and “Straw-board.” Chip-board is made from pulp formed of all kinds of waste paper. News-board is made from pulp formed of old newspapers. Straw-board is made from straw. These three different kinds of boxboard come from the paper dealers, or from the mills, in various sizes and thicknesses to meet all of the requirements of the box factory.

Chip-board is more generally used for all kinds of plain paper boxes. It is of gray color, and it has rather a rough surface. When the boxes are to be of good quality, like a candy box for instance, the chip-board is lined on one side with white news paper, or white book paper. This lining is done before the boxboard is cut and creased in shape for making the boxes. Many of the larger box-makers do their own lining on a special machine called the Parry Liner, which has been designed especially for the purpose. Other box-makers send the boxboard to outside concerns who make a specialty of lining board for the trade.

Chip-board, news-board or straw-board, when used for the making of ordinary boxes—shoe boxes, for example—is not lined. Better-class boxes, such as are used for holding collars and cuffs, silk shirts, handkerchiefs, neckwear, writing paper, and “white goods” of many varieties, should be lined with white book paper.

The first step toward the making of a paper box is in deciding on the proper measurements. The specifications must indicate the length, width and depth of the box, as well as the length, width and depth of the lid. The length and width of a lid, for a plain set-up box, must of course be slightly larger than the length and width of the box. To ascertain the correct sizes of both the box and its lid, the box-maker first makes models, and after these have been approved, the regular work of making quantities of the boxes is commenced.

Robinson Double Rotary Cutter and Creaser.

The full-size sheets of boxboard are fed into a scoring machine which cuts and creases the sheets to the proper dimensions. Several pieces of board, of the size required for the boxes, or lids, are cut from the sheet with one operation. The machine is equipped with a series of rotary knives and rotary scorers, which can be moved and adjusted to the positions desired. The rotary scorers are like dull knives, and are set up a little higher than the cutting knives; thus they score the sheet instead of cutting completely through it.

Single scoring machines, which score and cut the sheets of boxboard in only one direction, are used in some of the box-making plants. In other plants double scoring machines, which score and cut the sheets in both directions, are in service. The double scoring machine is naturally a big time-saver on large orders for the simple reason that it cuts and scores, both ways, on the sheet without it being necessary for the operator to feed the sheets through the machine a second time.

The cut and scored blanks, when in flat form ready for cornering and folding, appear like this:

Figure 1. Showing blank for paper box, cut to proper size, scored,

but with corner-pieces not yet removed.

The next operation is in removing the corner pieces from the blanks. This work is performed with the aid of a cornering machine. There are single, double and quadruple cornering machines in some of the larger plants, but the single and double cornering machines seem to be the most popular. The single cornering machine removes only one corner from the blank with one operation; the double cornering machine cuts out two corners with a single operation and the quadruple machine removes all four corners with one operation.

Power Double Cornering Machine.

The cornering devices are equipped with cutting knives, arranged so that they may easily be adjusted. The guides may be adjusted so that many different sizes of corners may be cut out of the blank stock. As many as twenty or more blanks may be placed under the knives at one time. The double cornering machine has two sets of knives and guides which are adjustable to provide for the various sizes of blanks. In the same manner the knives and guides of the quadruple machine are adjustable to provide for many different sizes of stock and also various sizes of corners.

When feeding the blanks into the single cornering machine, it is necessary, of course, for the operator to feed the sheet four times before all of the corner pieces have been removed.

When the four corner-pieces have been removed from a sheet of stock, the blank has the following appearance:

Figure 2. Showing blank for paper box, cut to proper size, scored

for folding, and with corner-pieces removed.

Some of the box-makers who make a specialty of fine, small-size set-up boxes for the drug trade, jewelers, etc., have machines which score the blanks, and cut out the corner-pieces simultaneously. This device is for small work only, and its principal advantage is accuracy. When scoring and cornering small-size blanks separately, it is often difficult to have this scoring line in perfect alignment with the corners. On this special type of scoring and cutting machine it is necessary for the operator to feed one blank at a time. Cutting and creasing of this kind can also be done on cutting and creasing presses, with dies formed of steel cutting and creasing rules. This process will be explained in another article.

After the blanks have been cut, scored and the four corner-pieces removed, the blanks are then bent upwards on all four sides so as to put them in form for the staying machine operation. Several of the blanks can be bent partly into shape with one operation. The operator of the staying machine then takes each blank and properly shapes it into the form of a box as the stay paper is applied to each corner. The staying machine is equipped with a roll of narrow Kraft paper which is gummed on one side. The machine is also equipped with a water-pan and a roller which moistens the gummed paper as it passes along. The operator places one corner of the box in position on the machine; the head of the machine descends and affixes a strip of the stay paper on the outside corner of the box. The operator then turns the box in rapid succession while the machine “stays” the other three corners of the box. The cutting of the stay paper to the proper size is an automatic operation, and the device can be adjusted to cut off any length of stay paper. The stay paper placed on the outside corners of the box, holds the box together.

Power Corner-Staying Machine.

In the case of very small boxes and lids, the stay paper is attached by hand, although the machine is adapted to small-size as well as large-size boxes.