From: epona (firstname.lastname@example.org)
Date: 08/27/02-01:10:23 PM Z
This may be a silly question, but I am assuming you place the plate dead
center, right? Then what do you do about the pin in the center designed to
hold the record in place?
William Marsh wrote:
> You might try placing the plate on a turntable from an old phonograph,
> set on 33rpm (or slower). Turn on the turntable, pour on the emulsion
> in the center of the spinning plate, stop pouring before it reaches the
> edge of the plate. An amazingly flat even coating will be achieved.
> You can then turn it off, allowing it to spin down by itself. If you
> stop it abruptly you will get a wave of emulsion - a "hump" as it were -
> across the plate. The turntable must be very level, and the plate must
> be allowed to dry in place. If you move the plate before it dries, you
> will affect the evenness of the coat.
> This should work for plates up to about 11x14 on 18 guage copper,
> somewhat larger on lighter plates. The motors of turntables were not
> designed for this, obviously, so weight of the plate, as you go larger,
> becomes a problem. You might have to help the spinning get going on a
> really big plate.
> Plate spinners were used in the printing industry for years, but now
> with everything going digital, nobody uses them anymore. It could be
> possible to find one at a graphic arts salvage place for a good price.
> One drawback is the emusion that is slung off during coating, but the
> evenness you can achieve is amazing.
> Oh yeah, I forgot that it really helps if the plate has been
> "de-greased" before coating. This allows even wetting over the entire
> surface. In other words, if you run water over the plate, and the water
> doesn't run off in a smooth sheet (if it "beads up"), then the plate
> needs to be degreased: scrub the plate with alcohol, then rub the plate
> with a mixture of water and pumice powder (hardware store) on a paper
> towel or sponge. DON"T TOUCH THE SURFACE OF THE PLATE WITH YOUR
> FINGERS, or you'll have to start over. When you rinse the plate, after
> these treatments, the water should run off the plate in a sheet, no
> beading up. Let it dry, then coat.
> > Margery wrote:
> > Nothing as interesting as when is porn porn, the meaning of
> > postmodernism,weston's peppers and the value of contemplating women's
> > breasts. Just a mundane inquiry: I am trying to coat the metal plates
> > supplied by Rockaloid with Ag Plus emulsion. They recommend pouring a
> > small puddle onto the middle of the 4x5 plate and moaving the plate
> > around so the stuff is distributed, and using a finger to push it
> > toward the corners if necessary. Using a finger doesn't work at all
> > for me-- and I am not getting anything resemble even coating although
> > the emulsion is liquified as per instructions.I've tried a foam brush
> > an d hake brush too, with very messy results. I'm new to liquid
> > emulsions -- are some better than AG Plus for working on metal? or
> > paper? All responses much appreciated.
> > Also -- could someone reind me about how one accesses the list's
> > archives? Thanks.
> > Margery
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "The most beautiful thing we can experience is the mysterious. It is the source of all true art and science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead; his eyes are closed." -Albert Einstein
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