One-point Lesson : Registration Marks
Lesson #7: Cutting the registration marks ...
Cutting the registration marks for a woodblock print - the kagi (the 'L' mark) and hikitsuke (the straight mark) - can be a difficult process. If the colour masses are large and/or roughly cut, the registration is sometimes not so important, but if fine lines are part of the design, it becomes a critical matter. If the hikitsuke is misplaced by even a hair's breadth, the movement on the far side of the paper is magnified by the 'pivoting' action, and unacceptable mis-registration will result.
Just as important as the position of the marks though, is their depth. In the ideal situation, the 'shelf' that is cut (on which the paper will rest), is no deeper than the actual thickness of the paper itself. Cutting it much deeper will mean that the paper becomes 'bent' when it is inserted, and accurate registration will be difficult.
But when carved areas of the block lie near the areas where the marks are cut, another problem arises - both the pigment brush and the baren come in contact with the marks. Not much can be done about the brushing, and small smears of pigment will be noticed on the margin of many woodblock prints in the area of the hikistuke. The baren problem though, cannot be ignored so easily. If the baren passes over the registration mark during rubbing, it is very likely to be abraded by the contact with the wood at that point. The bamboo cover will become worn far more quickly than it need be. It will also pick up pigment from the wood, and smear it over the back surface of the paper.
One solution is to recess the registration mark - both the 'shelf' and the wood that surrounds it, by a half-millimetre or so. There is a trade-off here - recessing too deeply will cause the paper to curve excessively ... but not recessing at all will result in damage to the baren.
And I'm sure that anything that helps extend the life of the bamboo cover will be appreciated ...
(Illustration courtesy of [Baren] member John Amoss. Thanks, John!)