Hello everybody.
This is an overview of practical KABK screenprinting info to help you streamline your production.
It's a lot, I know...
01 SIZES
1 table fits A0 (841 x 1189 mm)
consider to combine 2 A1 stencils on 1 A0 screen (and cover one half while you print the other) to save time.
2 tables fit printsize 560 x 760 mm (= between A2 (420 x 594 mm) and A1 (594 x 841 mm))
an odd size, but paper bought by the sheet in most stores come in 50 x 70 cm or 100 x 70 cm, so that's a good thing.
02 FILM
Should be flat, toner (whatever your use should be really black)
Please note that halftones can not be cut without making ugly lines in the print.
Good quality laserprint on halfmatted plastic-like A3 film:
go to 'edele technieken', down the stairs at etching room, ask Marijn Rietveld on mon-tue-wed
or buy it yourself and use any decent laserprinter.
Larger sizes:
If the design allows it: make a montage of A3's with transparent tape.
2 layers overlap is okay, 3 is too much (the UV can't pass through).
Larger sizes without montage, outside KABK:
cheap photocopy on transparent paper from a roll (usually 90 cm max.):
- Repro v/d Kamp, Wegastraat 40
- NDR, Valeriusstraat
KABK photography dept., Martijn Valkenburg, is supposed to have a large Epson inkjetprinter.
you could ask for the matted film from a roll, but I'm not sure they still do it.
03 SCREENS (zeven)
It's your job to check in time with Dodog or Martin if the screensize you need is available!
04 INK
Unico AQ (waterbased for paper) ink is sold by Goedman
TIP! Share colours with your group, make sure there's enough transparent base, and buy a liter of retarder as a group.
I will bring empty pots + lids to mix and store.
05 PAPER
Roosje is trying to get some sponsored.
If this doesn't work out, keep in mind that the moisture in the ink affects the paper.
The more ink (large solid areas), the more impact. Keep that in mind choosing the right weight.
06 NEWSPRINT (krantenpapier)
Essential tool to get going and repair stuff while printing, make sure you have it at hand.
Does the KABK shop (openings hours?) carry it?
07 DETAILS
Smallest printable elements (lines, type, pixels in bitmapped images) should have a minimum of .5 mm in positive and negative. There will always be even smaller elements (i.e. the endparts of serifs in type), but if you stick to this rule of thumb, you're avoiding lots of trouble. Zoom in and check this!
08 HALFTONES
Photographic images or grey scale textures from Illustrator can be screenprinted if you transform them to halftones in PhotoShop.
If you use a PostScript laserprinter like in the computerlab, Photoshop will rasterise your image if you follow the guides below. When you go to Cito or Repros (who use relatively dumb large size copymachines) the info below is used to incorporate the halftone-info as a bitmap.
Because of the 120 T screens for paper, and the waterbased inks we use, this STANDARD method usually works best:
- 18 lines/cm = 45 lines/inch = technical maximum
PLEASE NOTE THAT 10% BLACK POINT IS MINISCULE AND WILL DRY OUT ALMOST INSTANTLY
THAT'S WHY MY ADVISE IS:
less lines like 15 l/cm = 37 l/inch means cruder halftones, are can also beautiful (if the dimensions of the image are not too small) AND MUCH EASIER TO PRINT!
other halftone settings
- angle first halftone 22.5 degrees, each following layer (CMYK) + 30 degrees (unless you like moiré)
- elliptical dots
Feel free to experiment using other angles and dots (it's fun!), but whatever you try, make sure to stay UNDER the 18 lines/cm = 45 lines/inch!
ABOUT PRINTING RESOLUTION
The large photocopying machines at repro services used for cheap film on transparent paper from rolls don't print over 150 dpi, so this is the preferred resolution you give to them in PDF format.
Please note that making the transition from greyscale to bitmap, very high resolutions like 1000 dpi, give more refined bitmapped halftone dots. Try it if you like at 100% printing size, but make sure to lower the resolution to 150 dpi when you're ready for filmoutput.
If you rasterize your image through a Postscript laserprinter like the one in the computerlab, the dots will always look more smooth due to the higher printing resolution.
09 Clothing
Bring an apron or old clothing!
10 TAPE PLAKBANDBring plakband: the normal, plain stuff.
