Wrinkles and Paste

Mitsumata Washi; wrinkled with drying.

I printed up another smaller batch of my Chess/Horse prints but I ended up with some badly wrinkled prints so I got to finally try my hand at wet-mounting thin Japanese paper onto backing sheets.
The ones that wrinkled were all printed on a beautiful new paper that I was trying out--a 100% mitsumata paper that I got from New York Central Art Supply in NYC.
Not only do they have a great selection of European and Japanese papers but they are also arranged so that you can see and touch the various papers and compare the weights/surfaces/opacity/etc of papers that I've read about but never seen/touched.  They have a great selection of Japanese washi but also Thai and Korean papers in addition to Western printmaking papers. Many of their papers come from the Japanese Paper Place and there were a bunch of papers that I had never heard of.
I bought a bunch of stuff--Kozo, gampi, mitsumata and pulp papers--mostly artist grade but a few student papers to try out and test for future classes.
I also bought 15 small sheets of this shimmery, 100% Mitsumata paper ("Mitsumata letter-size") that was about 30g/m2. It has a lovely feel/hand and since I've had some luck with sizing and printing on thinner papers I thought it would probably work well.  I sized it during one of my sizing sessions with the same recipe I use for heavier papers (14g animal skin glue and 5g alum).

It printed beautifully. It really gave crisp, lively, sharp colors and the added body from the glue made handling and printing on it fairly straightforward. (It actually printed nicely unsized too) The only problem I've noted (on three separate printing sessions) is that when it dries it puckers very badly. I think it may be from uneven stress during printing but it's happened when the papers have dried pressed between books or under weights.

So I wasn't happy with the idea of pitching the 5-6 excellent copies of my little Horse print just because of wrinkling.  (And I still have 13 sheets left).
So after about 30" cruising the web and youtube for tutorials on wet-mounting prints I was ready to give it a try.
(Henry Li's Blue Heron Arts site has excellent tutorials/youtube videos of how to wet mount washi onto other papers. (www.youtube.com/watch?v=ii8ubo1jv1A)

Using a blend of 1/4 cup flour, a pinch of alum, and about 3-4 cups of hot water I made a glue-soup about the thickness of whole milk. This was brushed onto the back of the prints (face down on a waterproof surface across the entire print and off the edges...the moisture in the glue helps "float" the paper on the surface. A sheet of thinner-grade Japanese paper was then laid across the back and burnished in place with a stiff brush and then my softer baren.  The edges of this sheet were then brushed with the same paste and the sheet was lifted and pressed onto a drying board to dry/shrink tight. The print is now face up, glued to the backing sheet; and the backing sheet is pasted along the perimeter only onto the drying board.

Once dry I cut them off and now they just await trimming.

They're flat, thicker and heavier now that they've been backed with good paper and they dried without the puckering or wrinkling.  In my haste I used organic flour that wasn't perfectly white and I had to fish out some bran flakes while I was gluing....and I used my regular printing brushes so got a tad of toning to the paper that makes them look vintage.  But it worked pretty well and even the copy I glued to heavier etching paper came out totally flat and looking good.

Finished print now mounted on a base sheet of Japanese paper.

Wrinkles are gone.