Introduction to Water-BasedScreen Printing with Dave Fortune
What struck me most about Dave’s introduction and the screen print suite was the complete absence of oil-based inks. This has made the process so much better than when I tried to produce posters in my kitchen and was screens with endless amounts of paper and turps, many years ago. Although I used water-based inks – acrylics – when they became widely available I had not realised that these had become industry standard. This has made the screen process far friendlier and seems to have almost completely removed chemical risk.
Dave showed us the process which used some of the same methods as litho; the Dale Rowney mark-resist 150 microns film, matt acetate, chinagraph pencil, Rotring ink &c. Methylated spirits seemed to play quite a role, especially in getting washes. Dave mentioned using sandpaper, and that multiple layers can be exposed at the same time.
Once again we each made a drawing- I did a vase of brushes but it seemed a little pale. Several of the drawings had deep black areas and very fine detail. Lunch.
Dave and Freya went through the screen photo-coating process, Dave did the first demonstration and a number of screens were then prepared. We were getting hands-on which was great. We each exposed a screen – a few drawings on each screen – then washed out the exposed area and put the screens into the drying cabinet – wet screens to the bottom!
Dave demonstrated setting up the screen in the printing frame, registration, mixing up the ink and we then got on with it. Registration was done on the two lower corners of the screen using little rectangles of stick back paper rather than marks. NB: Ink pots are not to go directly onto the vacuum bed, use paper to protect the bed.
With the screen raised off the bed and paper in place, vacuum on, holding the squeegee at about 45 ^ flood the screen with ink, i.e. push the ink up the screen. Then lower the frame to the bed and firmly press/pull the squeegee down screen. Raise the frame and re-flood the screen, raise frame completely, turn off vacuum and remove the print.
My print was ok, a little washed-out, I did several.
We had a demonstration of cleaning the screen and washing out the stencil – a weak alkaline with no environment or H & S issues – no X mark.
Washing out was simple and easy, reclaim excess ink, wash out ink from screen, brush on stencil remover both sides, wash out stencil from rear.
This was an enjoyable and successful day. Must make sure to see Dave before getting a screen exposed…
Screen printing is something I have done quite a bit of in the past, although always in an amateur way. I made my first screen in 1973 for mono-colour tee-shirts; in 1975 I remember printing some tee-shirts for the then trades union NUPE and experimented with flyers and posters for fly-posting – very common at the time.
I have an abiding interest in Andy Warhol and the Factory, still considered avant-garde and rather strange back then, and I tried out the mis-registering style. Not at all difficult to mis-register, my screen were invariably made from old wooden window frames, or for tiny ones, wooden picture frames from junk shops, with pieces of acrylic shirts stretched over the frames and held in place with a combination of thumbtacks, office staples and glue.