There are ranges of qualities to be had from a drypoint plate.  The important thing to remember is that the burr sticks above the plate.  Ink sticks to the plate in 3 places; the far side of the line on that burr, the valley caused by the needle, and the near side.  The amount of ink that accumulates is these 3 spots is determined by: 1) the viscosity of the ink 2) the nature of the material used to wipe the plate, and 3) the thoroughness with which the plate is wiped.

  The viscosity of the ink plays a role because it determines how quickly the ink comes off  the plate.  Viscosity can be determined by mixing the ink with oil; it can also be affected by temperature.  If the plate is wiped while it is hot, the ink will be less viscous and come off the plate more easily.

 The materials used to wipe the plate, traditionally, would be one of the following:  tarlaton, the hand (the heel of the hand), or paper.

 Tarlaton:

 Tarlaton, because it’s composed of thousands of threads, is able to conform to the surface of the plate and to wipe more closely around every burr. This provides the most accurate, but weak image from the plate.

 The Hand:

 The hand, that is, the heel of the hand sliding across the plate has a certain amount of firmness and glides up and over the burr creating fairly rich line. The hand is held straight with the outer heel of the palm down and brushed across the plate. The pressure used for most of hand wiping is comparable to sweeping crumbs from a tablecloth. The printer may want to put abrasive material such as dust, or black pigment on the ink accumulating ink. Other wise, the printer will make frequent use of his or her apron to wipe off excess.

Note: The barrier creams intended to protect hands from absorbing chemicals will become sticky and leave unpleasant and unpredictable streaks on the plate.

Paper wiping:

Paper, when slid over the plate, is harder than the hand and rides up and over the burr creating an even broader line.  Many printers develop favorite papers such as phone books or TV Guide pages that either fit their hand well, or slide across the plate well. One artist uses wood blocks wrapped in newsprint.

Abrasive qualities in ink

A fourth factor that impacts printing is the abrasive quality of the ink.  Inks which contain more bone black will wipe cleaner than those containing more vine or lamp black. Most etching inks are ground to a coarser texture than lithography inks. A variety of products to modify inks are marketed but few impart an abrasive quality. Adding materials such as Brasso metal polish to the ink will increase the abrasive quality when moderate amounts are used.

Retrossage:

Yet another factor which impacts printing is retrossage, which means rubbing back in.  Retrossage is done after the plate is completely wiped.  The plate is placed on a cold surface such as the jigger to the left of the hotplate.  An inky tarlaton is warmed on the hotplate as the printing plate cools.  The warmed tarlaton is then passed over the surface of the plate.  The pressure used at this stage is so light that it might be analogous to wiping a speck of dust from your friend’s eye.  The warm ink in the tarlaton will accumulate on the colder ink that is on the plate.  The image will become perceptibly richer.  One last enriching strategy is simply heating the plate after the process.  The plate seems to seat a fine gray film which will translate into plate tone.