[emf]

drdag, thanks for the words of encouragement. I’ve kept a separate buffing wheel for the rouge, but it sounds like I’m being much too careless leaving the bar and wheel out on the bench between attempts. I’ve ordered a few new buffing wheels that should be in this weekend, so I’ll try pretending the rouge is ebola.

Pobboravsky, I’m probably mis-using terms here. I’m using 16ga copper plates from Renaissance Graphic Arts. When they come, they look like supphaman’s first picture a few posts above. To start with, I was taking them straight to the buffing wheel with rouge or tripoli, and I’d end up with a nicely polished plate (save for the minor scratches), except a very slight waviness if you looked closely at the reflection. These ripples were all aligned in one direction, and I was assuming they came from the initial vertical lines you can see in the copper plate pictured. That’s what I meant by orange-peel, and sanding did take care of it.

When I was playing around with polishing the plates by hand (chrome oxide powder on velvet on a board), It looked like still only see two of the edges were getting polished unless I started to use a lot of pressure — I attributed this to the copper plate being having a slightly-curved surface. Maybe I bent it doing something stupid, maybe it just came that way. Anyway, I tried a trick I’d heard of overclockers using to ensure the surface of computer heat sinks were completely flat — take a piece of wet/dry sandpaper, lay it on a piece of glass (under a trickle of water) and sand it. I just held one edge of the sandpaper in place with my left hand (the wet sandpaper sticks to the glass pretty well to start with, so it’s not hard to keep it in place), and sanded the copper plate across it with my right hand — no holder, not very comfortable. To start with I’d only see the sandpaper scuffing up the surface on the two sides that had been polishing, but after 10 minutes or so the surface evened out. I was just using whatever 3M wet/dry sandpaper they had at the auto parts store, it wasn’t adhesive backed or anything like that.

I’m just making this stuff up as I go along… I haven’t gotten any plates polished well enough to send them out for plating, so I have no idea if what I’m doing has any value.

[emf]

Ah, it’s nice to see that I’m not the only one going crazy trying to get copper polished. I’m just getting started with daguerreotypes, and I’ve accumulated most of what I need except the plates. I expected there to be a learning curve to polishing the copper, but I’m amazed how steep it is. Granted, I’ve never tried to polish anything except for an acrylic ash tray in 7th grade shop class, but still…

I’ve tried a lot of different methods at random, and my best results look similar to supphaman’s picture. I start with 2000 grit wet/dry sandpaper on a sheet of glass to try to flatten the copper and get rid of the orange-peel. Then I move on to the buffing wheel (6″ bench grinder), sometimes with tripoli first, then to rouge. I get to a point where I can get light scratches in one direction, and rotate it 90 degrees and get the scratches lined up in the other direction, but they’re always there, haunting me. When I try hand-polishing it with powdered chrome oxide or red rouge, if I press lightly it isn’t enough to get the scratches to disappear; if I press a bit harder (or keep at it for a half hour pressing lightly), the shiny finish clouds up after a hundred passes or so.

So far I’ve had other projects to work on when I got tired of polishing, but I’m running out of distractions. It’s great to hear what’s working for other people, though, even if I can’t make it work for me.

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