Removing dirt and oxide from a 50-year-old zinc lithography plate?

February 25, 2024 11:37 AM

I have an etched intaglio plate from the late 70s, presumably zinc or zinc-aluminum alloy. I'd like to run a few prints off it, but it's got some small raised white spots which I'm guessing are zinc oxide in places. Anyone know of a way to clean/remove these without damaging the plate?

This was a plate my mom prepared in the 70's (she doesn't remember making it at all). The flip side of the plate indicates it's Ball brand "micro-metal", whatever that means. The raised white spots are about 2mm in diameter and maybe .5mm tall. There are maybe two dozen spots over the entire plate (which is probably around 6"x9"). Any ideas?

posted by phooky to Media & Arts (4 answers total)

Best answer: My memory is really fuzzy on this but I think we used citric acid to remove corrosion before drawing on aluminum litho plates. That would likely wreck the drawing if it's a litho (from your title) but I know absolutely nothing about etching or intaglio. I think litho on aluminum plates is pretty fragile. You could try finding an experienced printer to look at it. I've printed much older found litho stones so it may be possible.
posted by sepviva at 8:56 PM on February 25

What I would do is get some really fine grit sandpaper - 1000 or higher and tape it to something really flat and smooth. Most people will use a piece of glass or a window pane, but this is easier to do flat. Spritz some water on the sandpaper and wet sand the plate gently. It should remove the high spots and polish the plate. To make it easier, I would put masking tape handles on the back side of the plate.
posted by plinth at 6:17 AM on February 26

Best answer: It's really important to know if this is an intaglio plate or a litho plate -- they're two entirely different processes. There's a standard process for cleaning and polishing etching (intaglio) plates which would destroy the surface of a litho plate. I think you have a photoetching/engraving plate but without seeing it I'm not sure.

Do you have a local college or university with an art department that teaches printmaking? Asking an expert is the right and easy choice here. Also, where were you thinking of printing it? Because that will require a press that is surely adjacent to a printmaker -- whom you should ask.
posted by obliquicity at 5:04 AM on February 27 [2 favorites]

Response by poster: Thanks-- it really sounds like consulting a printmaker is the way to go. I'll poke around and find one!
posted by phooky at 6:05 PM on March 1