Thursday, April 15, 2010

Registration Simplified

Being an over-efficient maniac, one of the things that has always bothered me when printing a la Japanese, is the registration method used in moku-hanga. Don't get me wrong, I have faithfully cut kentos in every block just like the old methods explain. But I believe this way of doing things introduces a margin of error for every single block that is cut. I'm sure the masters, er, mastered this kento cutting so that they were identical for every block.

In Western printing, long ago I started using registration boards. I've made them mostly of foam-board so that they could be fed through the etching press (or hydraulic press). A registration board is simply a "movable kento" system of registration. Any two pieces of material glued together as a square corner, then another piece of material as a paper guide glued at some pre-determined margin. Not really a complicated device. There is some error introduced in that the block has to be placed exactly in the same place every time, but in my experience this is less prone to error than having to cut exact kentos in as many as a dozen or more blocks. Seems that every kento in every block could introduce some error into the registration process and I would rather spend a little time upfront into building a semi-permanent movable kento.
With a well-built registration board, the only but very important requirement is that the blocks have to be cut perfectly square, the paper has to be cut perfectly square and the placement needs attention, but no more attention than if placing paper on a standard cut kento.

When I started printing with waterbased pigment, the dampness of the whole process was not compatible with a foam-board registration jig. So I made a prototype of wood with a 1 inch margin wood paper guides built in. If I want other margins, as for the tiny tigers, I just glue kento-mat-board to the board at the appropriate distance. You can see the margins of the tiger prints in burgundy matboard. They are glued with paste so they just come off by a bit of soaking and scraping. The wood guides are glued with white glue, also steady but removable with a bit more effort.

I used cheap wood and simple staples to see if the board worked okay for printing but I was careful to use a square at every step to make the board corner and the kentos a true 90 degrees. Also, the "ruler" is just cheap wood I had around the studio; I used it because it is slightly lower in thickness than my blocks, allowing the baren a free "ride" over the printing area without fear of catching on the registration guides. After a few prints, I brushed the whole board and mat-board kentos with clear acrylic to make it easier to repel water and clean pigment and paste off (not that I'm messy or anything).

Once I was satisfied that this was a suitable movable kento for woodblock, I made myself a slightly fancier board. This time I used a nice board for the backing and brass corners and straight pieces for the "kento". I brushed it with polyurethane again to make cleaning easier and installed semi-permanent one-inch and two-inch margin kentos. Despite the polyurethane, matboard still sticks to the wood, so I can still temporarily "install" a shorter or longer margin. Also the screws can be removed and the kentos moved according to my next project demands. I screwed the brass pieces quite firmly so that there would be absolutely no gap between the board and the brass kento where the paper could slip in. The whole board sits on a sheet of slip-proof drawer liner, which I also use sometimes directly under the block.
And again, I emphasize, the corners must be perfectly square, as the blocks and paper.

Much prettier, easier to clean.
Perfect registration is now a breeze, no need for cutting kentos on every block and wasting all that time and wood. Baren glides over the board without problems, cleanup a mere wipe with a damp towel, can life get any better than this?

3 comments:

  1. Question - How do you adjust for varying thickness of blocks? All of mine are not always the same measurement. Cherry is different from Shina, etc. I'm sure you have a remedy for this common problem. ;-)

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  2. Hey Sharri!
    Two solutions for that. I either work on 3/8" Shina or 3/4" cherry, so the obvious first solution is to have two registration boards, one for the thinner woods and one for the thicker woods.
    Really the "thin" registration board would accommodate a range of blocks from 3/8" to something as much as a 1/4" higher without any problem.

    But there is another solution, really two. One is to have a couple of pieces of thin wood handy to "raise" the brass kentos. The kentos are removed, thin wood goes on the marks, kentos are screwed down again, holding the shim-wood in place. Tacked on pieces of matboard can be used to raise the paper, or the shim-wood can include a "shelf" for the paper to be the same height as the block.
    The other is to raise the entire, and already squared, corner wood pieces with kentos attached. The pieces are just tacked on with white glue to the backing board and then screwed down in four places. All that is needed is to remove the screws, gently tap the wood off the backing board, insert shim-wood as high as you want to go and screw the whole corner assembly back down. If you almost always work with similar wood sizes, this would take five minutes and you can have ready-cut shims for a variety of block thicknesses.

    Hope all that made sense. I personally have two (at least) registration boards.

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  3. Very cool. I've more and more often been using a registration board rather than the cut-in kento. For me it's not so much about not trusting the accuracy of the registration as it is about wanting to use the entire block for image area & not wanting to "waste" any of it on border space. I've been using a reg. board from McClain's, but you've given me courage to try making my own. And thanks for the tip about covering it in a layer of clear acrylic for cleanup. Mine's a mess!!

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