The polyester plate litho process is neat. You can create the plate in either a laser printer or with sharpie markers or anything else that is waterproof and permanent. So making the plate is quick and easy. The plates are also cheap, less than a buck each for a 8 1/2 x 15″ sheet. (side note… I like the gocco process as well, but the screens are pretty expensive, not to mention the lightbulbs to expose them, etc.) One plate lasted for about 40 pulls before it seemed to deteriorate, this may have been my fault of rolling up a stiff ink and it pulled the toner off. The fidelity is what I was really drawn to, it’s about as detailed as the toner decals if the ink consistency is right. The only draw back is it doesn’t lay down a lot of ink, a very thin layer, so I think the challenge will be getting opacity and color from a very thin layer of glaze. If you try and ink it up a lot, the details get lost and the ink bleeds when it goes through the press.
I got the first batch out yesterday morning, they turned out ok. The fidelity is there, the images are a little light as expected, then again I wasn’t going for colors this round, just durability of the print on the pot when fired to 04. Most of the recipes were 50% oxide or less. Obviously stronger colorants (iron & black mason stain) showed up the best. I also tried some white on black glaze, the zircopax ones showed up pretty nice on my black glaze (McFarling Black) but scratched easily, so I wanna try it again with the durable recipes and over top a glossy glaze (mcfarling black is kinda matte so I wonder if the glaze underneath is more prone to scratching).
I did a few different frits (3110, 3124, 3134), some alone, some with feldspars some with clay and feldspars. The 3124 and 3134 seemed best but I may be biased cause they had the strongest colorants as well. The oxides alone did not adhere to glaze well, or they peeled off as the decal burned off. Here’s the recipes I am concentrating on for the next round where I will vary the percentage of colorant. Keep in mind I am not much of a glaze chemist, I am more of a experiment see what sticks kinda guy - emperical me! My daughter Iva got a “Eyeclops” for christmas, it’s like a powerful microscope with a video camera that hooks to the tv. Very cool, you can see little specks of iron the size of silver dollars on the screen and can see microscopic images of the glazes.
Black Ink #3
Printed Decal and Test Tile
Tile Detail
Microscopic view of half-tone screen 60 dots per inch
Lavender Ink #2
Printed decal sheet and test tile
Detail, you can’t see that it printed much at all unless you look at it with a glare, as shown here.
For some reason I am hungry for Grits now! |
Iron Oxide Ink #1
Printed Decal and Test Tile
Tile Detail
Microscopic view. This is of Shiva Shazam Man’s Eye and top of nose (slightly rotated clockwise).
White (Zircopax) on Black Glaze
Detail
Detail with the Eyeclops. Half tone screen at 60 dots per inch. |
Ink #1
3124 90
EPK 10
Iron Ox 20
Came out sepia toned. Very durable. Of all the inks for this next round, this one seemed to melt into the under lying glaze the most when you look at it in the microscope (blurry edges at the microscopic level, not at the visual level).
Ink #2
OM4 65
3110 25
Silica 10
Lavender Stain 30
Very very faint color, however the stain is a light value, on top of a clear glaze over a porcelain clay body (what did I expect) anyways and the percentage is way down, so I think it has potential to be a nice opaque ink. I’m not sure why I used a ball clay instead of EPK (may try it both ways next time), but it makes for a very durable image in addition to retaining high fidelity under the microscope (sharp edges).
Ink #3
3134 33
Black Stain 33
Bentonite 33
I’m going to try this one with and without the bentonite since I never did a 3134 alone in the first round. Nice image fidelity, durable, and a very simple glaze. I am not sure if it’s the stain, but at 33% the image in a dark charcol, looks nice in contrast to the sepia toned one. Since the image looks the best with this one, I wanna see what other colorants looks like. At the microscopic level the dots have a halo effect, you see where the dots originally was, and the glaze melted and contracted? kinda? Anyways makes for a sharp image. BTW, this one printed sharp, however the ink was “gritty” compared to the other mixes.
All of the dry materials are mixed with a transparent lithography ink, mixed very stiff, I only add enough ink to dissolve the dry materials to start with, then I add a #2 burnt plate oil (same oil as the ink, but a thinner consistency) and add only enough to get to gloss over but still “stand up”. It’s not accurate but I was trying to be consistent between batches, basically 10 grams total of dry materials to 1/2 table knife of ink. And then a small daub of the burnt plate oil.
yack yack yack yack… Anyways I think once the recipe is right, I’ll try making decals using both wood cuts and the gocco which will lay down more ink, but be less detailed. Maybe a combo of techniques based on the image I want will be the ticket.
