Part 6 (2/2)

There is no good in taking up with the brush a large quant.i.ty of lye or turps, and to shed it at once. Yet this is too commonly done, regardless of waste. In order to wash a form well the brush should be pa.s.sed lightly over all the pages, in order to wet them uniformly. Then they should be rubbed round and round, and finally lengthwise and crosswise. Leaning on the brush not only wears away the bristles, but sometimes injures the face of the type, too. It is a bad practice.

After was.h.i.+ng, before printing, a sponge with pure water should be pa.s.sed lightly over the form, and then the form should be dried with a cloth.

Care should be taken not to use a woolen cloth, which is liable to leave little pieces on the face of the types, and to see that there are no hard substances in it. After printing it is always best to wash with turpentine. Lye induces oxidation of the types, while turps leave an oily film on them, which preserves them from the action of the atmosphere.

HOW TO PREVENT OFF-SETTING.

A practical pressman says that a sheet of paper wet with glycerine and used as a tympan-sheet will prevent off-setting. This will be found better than using oiled sheets.

PRINTING ENVELOPES.

To prevent the lumpy particles of mucilage on gummed envelopes from ”battering” the type, use a heavy piece of blotting paper as a tympan, and when beaten down, touch the injured part with a drop of water, which will bring up the impression again.

TO PREVENT SET-OFF ON WRITING PAPERS PRINTED ON ONE SIDE.

To prevent set-off on writing papers printed on one side, do not lay the sheets straight as they leave the press or machine; this will enable the air to get between them, and wonderfully expedite the drying of the ink.

Do not allow the heap to become too heavy.

A QUICK DRYER.

A quick dryer:--j.a.panese gold size, 2 parts; copal varnish, 1 part; elber powder (radix carlinae, carline thistle), 2 parts. Incorporate well together with a small spatula, and use in quant.i.ties to suit the consistency of the ink employed and the rapidity with which it is desired to dry. The usual proportion is a small teaspoonful of the dryer to about one ounce of average good ink.

TO PREVENT WARPING IN BLOCKS AND WOOD.

To prevent warping in blocks and wood-letter used in large bills, a French printer advises that they should be placed in a zinc basin, provided with an air-tight lid; they should then be thoroughly saturated with paraffine oil, and left thus for about four days, when they should be wiped with a clean dry rag. Prepared in this way when new, wood-letter resists the effects of lye, petroleum, turpentine, and atmospheric changes.

HOW TO KEEP ROLLERS WHEN OUT OF USE.

It is a good plan, when rollers are to be kept out of use for any particular time, to put them away with the ink on them. It protects their surface from the hardening effects of the atmosphere, and causes them to retain those properties which give them the much desired ”tackiness.” But about half an hour before using them, remove the ink and see that they are really in condition again.

PRESERVATIVE OF ROLLERS WHEN NOT IN USE.

The following preservative of rollers when not in use is often applied:--Corrosive sublimate, 1 drachm; fine table salt, 2 ozs.; put together in 1/2 gallon of soft water. It is allowed to stand 24 hours, and is to be well shaken before using. Sponge the rollers with the mixture after was.h.i.+ng.

OILS FOR LUBRICATING ROLLER MOLDS.

Sperm and lard oils are the best for lubricating roller molds. If they are properly used, no trouble will be experienced in drawing the rollers.

CARE OF ROLLERS IN THE SUMMER TIME.

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