I spent a fair amount of quality time this weekend in castle daguerre. Several hours were devoted to experimenting more with polishing plates. Since I was dissatisfied with my copper polish in the last go round, this time I worked on a sixth plate that I have that was donated to me by a daguerreian friend. It is already coated with silver and has been used a number of times, so it was a perfect practice subject. I wanted to see in what way working with the silver is different than the copper.
I have several types of alumina slurry that I am using with my Bosch random orbital sander. (5.0 mic, 1.0 mic, 0.3 mic and 0.05 mic). I have foam pads that fit the 5″ hook and loop plate on the sander and I use a separate pad for each micron size of slurry.
Initially as a plate holder I was using a 14″x14″ piece of 1/8″ acrylic that I had glued a thin sheet of polycarbonate to that had a sixth plate size hole cut out in it. This created a square “well” for the plate to sit in that allowed me to polish without actually fastening the plate to the holder. It worked decently enough, but there was some “chatter” of the plate because the square hole was very slightly larger than the plate. I also found that when I changed slurry types, the well had a tendency to be harder to clean thoroughly. I tried this design because I didn’t like peeling plates off the double sided tape that others use, fearful that I would bend them. The original plan was to create a “well holder” for each polishing compound I use so cleaning wouldn’t be as much of an issue. Multiple holders have not yet been made however.
In the end though I went back to the double sticky tape on a plain sheet of acrylic. After I experimented with the tape a bit, I found that about an inch long piece held the plate securely but still allowed it to be easily removed using a sharp knife slid carefully underneath.
For my method I would squirt a puddle of slurry on the plate about the size of a quarter and then run the ROS at the lowest speed for about 3 minutes. I would then detach the plate, rinse it in tap water and then isopropyl alcohol and dry with a piece of clean paper towel.
I did find that paper towel is too rough for silver. Even when used very lightly it can create the odd random scratch. I think on my next attempt I will try using a cotton ball to rub the leftover compound off the plate. The simple sheet of acrylic (no “well”) was very easy to clean. When I ramp up to multi-plate production I will probably use a separate sheet of acrylic for each compound to reduce the chance of cross contamination.
I still do not have the rouge I ordered to do the dry polishing step, I plan to try the ultrasuede that Irv Pobboravsky recommended for my buffs. I have to order that and decide on a buff design. I have the lampblack, but I need to get it into a nylon stocking “duster” as Mike Robinson recommends. Otherwise I will have a really big mess on my hands.
I was pretty pleased with the polish I achieved even without the final steps, but did have the odd thin scratch here or there. I can see that rigorous adherence to cleanliness is going to be critiacal. I also have a plate from the same friend that was polished by a well know daguerreian. He loaned it to me as an exemplar. I still have a ways to go before I have a perfect match with the “pro” plate, but it feels more like it might be within reach. I did notice that the plate I polished had a sort of “waviness” that the exemplar plate did not. It looked to me like the remains of some kind of milling process that maybe hadn’t been removed at an early stage. It was very hard to see unless the plate was held at just the right angle. Overall though I would have been able to use the plate I made and it would have taken an image.
My second project was to try my hand at iodine fuming. I charged up the fuming box I am using some weeks ago and I figure it is stabilized now. I took another gift plate I have that has been polished before and set the fuming box up in my hood along with a sheet of white paper and a 7.5 watt bulb to view the changing colors. The plate polish is not perfect, but since I had no intention of making an image, I decided it was good enough.
I ran into one complication right away when I discovered that my sixth plate was very slightly larger than the opening in my fuming box. Next time I will check the fit in advance. For this experiment however I just forged ahead as best I could. I put the plate down, opened the cover glass, fumed for five seconds and then closed the cover and pulled up the plate to take a look.
I couldn’t see a damned thing. Another 5 seconds. Nothing. 10 seconds. Nothing. 20 seconds – nada. This went on for a while. After 2-3 minutes I “maybe” saw a light rose blush – but then maybe it was my imagination. Eventually I would play a complete round of solitaire on my iPhone between looks. Eventually the color got obvious. The plate color was very uneven. My fellow editor Alan at cdags.ord tells me that this is mostly the result of uneven polishing. Since I hadn’t really polished the plate, that made sense.
So what was going on? My conjecture at this point is that the iodine box was too cold. The castle is unheated, and the outside temp today was in the low 60′s. The castle further sits in a fairly shaded area. I imagine I will have to put a thermometer out there and warm up the box a bit prior to use. I can also see that hitting a particular color is definitely going to take some practice. Still it was pretty great seeing the change taking place – just like in the books. I took a few pictures.
My goal seems that much closer. As I sit typing I notice that I have some iodine stains on my hands. They likely won’t be the last.