Setting up a press
The art of erecting a press out of the various pieces in which it is constructed for the convenience of being removed. The following directions will be useful, especially to provincial and colonial printers. The Columbian press is put up as follows:
When you have the staple on the spot where you intend it to stand, put the feet on their respective places as marked, and raise it upon them; then put the bar-handle in with the bolt as marked; then put the principle lever into its place, and put the bolt in which connects it to the staple; then put the angular or crooked part, which has three round holes and one square hole, through it into the mortice, which is in the projecting part of the long side of the staple, and put in the bolt that attaches it to the staple. In the extremity of the edges of the heads of those two before-mentioned bolts you will observe marks, and corresponding marks over the holes through which they pass; put the bolts in so as the said marks meet together and correspond, and so on until you have all the remaining parts in their respective places.
Put on the ribs, and having made them perfectly straight, screw them tight to the staple. This done, lift the press-table into its place, and attach it to the rounce with the girths; the press being now ready for the platen, put the four screws which have heads on one side, intended to attach the platen to the piston, and screw on the nut belonging to each.
The press-table being properly adjusted with a spirit level, fix a bearer at each corner and one in the centre, and lift the platen on them. The platen being fixed straight, raise the screws in the piston, and roll in the platen as it is fixed on the bearers on the table, until it is exactly under the piston, when the screws, already in the piston, are fixed with their heads from you, into their proper plates in the platen, and secured by the four small blocks of iron which accompany them.
After putting the necessary number of tin or iron plates under the piston, bring the bar-handle over till the piston and platen come in contact, and hold it there till each nut is screwed tight with the hand. This done, give each nut one turn or so with a screw-key. It being these plates of tin or sheet-iron which increases the impression, care in ascertaining the proper number required will obviate the necessity and save the trouble of either adding to or decreasing the number after the platen is screwed up and adjusted.
In adjusting the platen, make a gauge that will exactly come between and touch the platen and the table, with the bar-handle at rest. With this gauge, which may be made of two four-line quotations, and justified to the proper height with paper, card, or leads, try whether the platen is exactly parallel with the table, by rolling it in and inserting the gauge under each corner of the platen. If any part of it be thus found lower than the rest, it must be raised, by turning a little the platen screw next the part to be raised. Again try the gauge, and if not yet exactly true, again screw the nut a little next the part affected; half or quarter of a turn will make a great difference. By thus gauging and tightening the nuts, the platen may be adjusted to a mathematical nicety.
It is necessary always to keep the proper side of the connecting rod up, when you have occasion to take the bolt out of the elbow of the bar, either to increase or diminish the power; increasing the power is effected by turning the rod so as to shorten it, and decreasing it by turning it the contrary way. By the nut on the iron screw, which connects the main and top counterpoise levers, you are to regulate the ascent and descent of the platen, so as to clear the head-bands of the tympans, which is done by screwing the iron nut up as far as is necessary. The small holes which communicate with the respective bolts require a small portion of pure sweet oil occasionally, and the use of the purest Florence flask oil is recommended as the cheapest in the end, which has been experimentally proved. You may easily judge whether every thing is put in its proper place, by the perfect ease with which the bar-handle moves when put up.
In your commencement of working, let your impression be rather light, and increase it by the before-mentioned means, until you have obtained such an impression as is desired. The pressmen should take all the cylindrical bolts out of their respective places once a week, taking out one at a time, cleaning and oiling it, and putting it into its place again.
The manner of setting up an Imperial press is somewhat different:
First, put on the legs to their corresponding marks on the staple. After you have placed the ribs to their marks, and before you have made them fast, see that the table runs true between the cheeks of the staple; then screw them fast. Hang the platen by its screws to the piston; observing, by the marks, that the screws and cotters are each in their proper holes. The attachment and adjustment of the platen are the same as in the case of the Columbian press. The bar-handle, the rounce, the rib stay, &c., as they can only be put in their respective places, need no directions. The small round bar of iron sent with the press is called the oiling-bar. When the press requires oiling, bring the bar-handle home to the cheek, then place the oiling bar between the head of the press and the flange of the piston; which, taking off the power of the springs, sets the working parts of the press at liberty; you can then with ease take out the main bolt, chill, &c., and after oiling the bearings, replace them in the same manner as before (the parts marked “front” must be kept to the front of the press), and removing the bar, the press is again in working order. The screw in front of the piston is connected with a wedge, by which you may with perfect ease at all times regulate the pull to your work; observing that the pull is correct when the screw is about half way out. If the impression is then too light, place between the two wedges at the back of the piston a strip or two of tin, or as many as will give you the power required.
After the platen is by this means once properly adjusted, it will not at any time need (as some presses do) to be unscrewed, iron or cards to be introduced between the piston and the platen, and a re-adjusting of the platen. The wedge will then act properly, and by screwing it in or out, the impression will be light or heavy, as the work requires; taking care, whenever you use the screw, to fix the oiling-bar as directed to be done when oiling the press.
The press is always working to its full power when you bring the bar-handle home to the cheek of the staple; and, whether the work requires a light or heavy impression, should always be so worked. The same observations respecting oiling and keeping the Columbian press clean, are applicable to the Imperial press.
Setting up a press
The art of erecting a press out of the various pieces in which it is constructed for the convenience of being removed. For the mode of setting up different kinds of presses see directions under the heads of Columbian Press, Imperial Press, and Albion Press. The small holes which communicate with the respective bolts require a small portion of pure sweet oil occasionally, and the use of the purest Florence flask oil is recommended as the cheapest in the end, which has been experimentally proved. It is easy to judge whether every thing is in its proper place, by the perfect ease with which the bar-handle moves when put up. In the commencement of working, let the impression be rather light, and increase it gradually until such an impression as is desired is obtained. The pressman should take all the cylindrical bolts out of their respective places once a week, taking out one at a time, cleaning and oiling it, and putting it into its place again.
The second edition’s entry for Imperial Press was labeled Sherwin and Cope’s Press.