Re: solarplate images up on my website
Hi Judy, The problem we're having that might be causing these "measles", or splotchiness in what should be even tones is this: the plate suface is a little tacky. against that we place the Pictorico ohp film, which we've printed in an inkjet so it has ink dots on the surface. Those two surfaces grab each other, and then air pockets can develop during drawdown. The two surfaces sticking to each other don't allow the air to get pulled out from between them as it should. Kinda like putting a decal on glass, and getting little air pockets trapped. My thoughts about the slick white plastic are that it forms a barrier all around the plate as the plastic gets sucked up against the glass cover. That stops the air from having a way to escape the area of the plate. When I removed the plastic, the little open "valleys" in the rubber baseplate allow the air a route to the vacuum line that's evacuating the air. I'm going to replace the plate glass in the NuArc with a special Krene vinyl that is supple and thin (sounds like Gumby). Jon uses that. Maybe then I can smooth the air bubbles toward the edges during drawdown. whaddayamean, "solarplate (yikes!)" ??? whaddabout, Gumprints - yikes! those sound really scary! susan On 2/26/07, Judy Seigel <jseigel@panix.com> wrote: Susan, I covered the "bumpy surface" of the Nu-Arc bed with a sheet that was a kind of dull black mat vinyl on the top side with a woven (dark) fabric backing on the underside, BUT the surface was black... and, while it's true I wasn't doing solarplate (yikes !), it NEVER gave me any trouble. (The main operating problem I had with the NuArc, when it wasn't shorting out its fuse-erama, was the tendency to emboss delicate papers, and when I cut the pressure that vanished.) Frankly I'd suspect the white surface. It could well not be totally opaque, and could also also cause reflections, including from the upper glass (the one under the bulb), throwing other things off. I can't remember what that vinyl sheet was... Or where I bought it. I think probably the Rubber Store on Canal Street, now of course long gone. But I have some scraps around (I use it for a mouse pad, and made an eye patch out of it after some surgery)... and am pretty sure I can scare up a swatch to send you as a sample, if you like. (Do any plate burners expose onto white?) J. -- susan gravure blog at www.susanvossgravures.blogspot.com website www.dalyvoss.com
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