Recycling Plates

[Festus]

Okay, this might be stupid, but here goes….Is it possible to take the reject plates(under, overexposed, etc)and repolish, resensitize, and reuse them? Or do I need to have them replated?

[RonF]

The short answer is “yes”. This is what most of us do all the time. If you are repolishing a used plate, you shouldn’t have to remove much silver, so there will usually still be enough silver to resensitize and reuse.

If the plate had been treated with gold chloride, it will require a lot more polishing. If the plate has defects such as pits, then polishing won’t solve that problem. If you are dealing with antique plates and there was gold painted on, that spot always be there, in my experience.

I use old plates that were previously been ruined in some way, I was able to buy some that already had the images wiped off. When I started, I was doing much more polishing than I had to and I still usually had enough silver to do multiple tries on the same plate.

Modern plates may have less silver on them, in which case you would not be able to repolish them as many times.

[Festus]

Thanks RonF! That’s very good news for us guys just starting out. Thanks again.

[dagist]

Ron F. observed “Modern plates may have less silver on them, in which case you would not be able to repolish them as many times.”

It turns out that modern plates usually have much more silver on them than vintage plates, not less. Theoretically, you can reuse modern plates many more times than vintage ones. Your polishing technique will determine how many reuses you will get before the copper starts to show through.

Back in 1999, I made silver thickness measurements on both vintage and modern plates which showed that vintage plates usually have only about 10% of the thickness of silver that modern plates do. It of course depends on how much silver you have asked your electroplater to put on your modern plates. I used to ask for 1 mil of silver but now only ask for a half mil. Here are the silver thickness measurements taken from the center of eight different plates. The plating process will often plate more silver towards the edges of your plate than in the center, hence my .000851 measurement below was just under a mil for the center while the edges were just over a mil.

.000056″ 1850s plate #2

.000071″ 1850s plate #1

.000095″ Theis Plating–Ken Nelson

.000192″ Pierre Plating–Mark Kessel

.000202″ Pierre Plating #2–Mark Kessel

.000261″ Theis Plating–Tom Young

.000846″ Metal Finishing Technologies–Charlie Schreiner

.000851″ Buffalo Plater–Rob McElroy

Cheers,

Rob McElroy

Buffalo, NY

[Festus]

Thanks Rob. When I had my 10 4X5’s done I requested 1 mil. If it actually is, who know’s? Hopefully, I won’t be having to repolish them too many times before getting an acceptable image. But we know how THAT goes!

[photolytic]

Well said Rob,

One might also add the caviate that not all platers will give you what you ask for.

Witness the sad story told by Race in San Diego where he paid $400 for a few sixth plates with only minimal silver.

Trust in a plater recommended by another Daguerreotypist is usually safe, but if you have to find a new plater, good luck.

First, choose a plater with XRF thickness analysis equipment.

The coulohmb thickess meter which platers used to use puts a hole in the silver layer.

Pre-weigh the polished copper plates to verify the work of your plater.

Be upfront about this, telling the plater what you have done.

Supply him with a list of your original plate weights beforehand so he can verify your data.

Call this quality control.

Be sure to put in writing, on the invoice, that if his work does not meet your thickness specifications in the center of the plate by a reasonable margin (say 50%) you will send the plates back to him for additional plating at his expense.

Over a period of 10 years I have only had to do this with two platers and it has only taken one such experience for the plater agree to comply with your requests.

I actually brought my digital balance to their lab and weighed the plates there to prove my point.

[RonF]

Sorry about my mis-information re: new plates. I had seen so many stories about plating not being done to spec that I thought that many out there may not have as much silver. I did use the word “may”, but I should stick to things I know first-hand.

The part about old plates was based on actual experience, I have found that they can be reused several times providing you only do a light polishing each time.

[Festus]

Thanks guys. I’ll just stick with a light repolish and hope for the best.

[Mercury]

Festus,

Watch out with the “light repolish.” Enough repolishing has to be done to completely remove the traces of the old image.

Pay attention when you’re sensitizing a re-used plate… if your re-polishing hasn’t been adequate you will probably see a “ghost” of the old image reappear as the plate takes on iodide.

On the other hand, if you notice any greenish tints in what should otherwise be a nice gold-rose of silver iodide, you’re probably very close to having buffed through the silver in those spots. You’ll see that greenish tint when iodizing long before you see copper actually coloring through as you’re buffing.

Some platers will re-plate over old silver when it gets thin. My current plater, whom I would trust to plate my children, has advised me not to bring him my old, worn-through plates. He’s convinced me that new copper or brass will yield the best quality, and with most of the cost of the plate in the silvering, I believe him.

Welcome to the Club!

[RonF]

Mercury-

Love the line “My current plater, whom I would trust to plate my children…” !

Agreed that under-polishing can leave a latent image that could reappear. I had this issue more when I was recycling antique plates for the first time. I haven’t had this happen when rubbing off my own images. I am not sure if it is because my images are often under-saturated, because they are becquerel-developed, because they are not treated with gold chloride, or because I have become better at polishing.

Good to learn about the green tint on sensitizing indicating too thin a layer of silver. I was wondering how one would know when this was the case.

[Festus]

Thanks for the info Mercury Nelson. I’ll go a wee bit beyond the light repolish, then add a little more.

[Mercury]

Festus, I believe you’re on exactly the right track. Go a wee bit beyond the minimum, and then a little bit more. The Goldie-Locks principle applies very well to the daguereotype.

RonF, 99.999% of all antique plates you’ll ever encounter have been treated with gold chloride, so every one of them is a real grind, literally. I have two problems with re-using 19th C. plates… 1) if the plate is so bad that the original image is ready for destruction, I will go through the silver before getting it smooth enough to use again. And 2) if the plate is not bad enough to be ready for destruction, I can’t bear to be the one to irretrievably destroy a piece of history, no matter how small or insignificant. Who knows? Sorry, I’m sounding like a doctor on a TV hospital show I think, but I believe that working with one’s own new, consistent plates is the key to a successful future.

Becquerel or mercury, ungilded plates are MUCH easier to buff off.

Thanks for the appreciation of my weird humor. I don’t have children, but if I did, the threat of getting plated in an electrolytic cell would give a whole new meaning to the term “you’re grounded.” …Cathode? what a sweet name. Is that with a C or a K?

[photolytic]

Ken,

Your plater wouldn’t be named Dr Frankenstein would he?

Festus,

Sometimes a “wee bit” more polishing isn’t enough, especially if the image was gilded.

I usually double or triple the amount of repolishing to be sure.

Even if you don’t see a ghost of the old image during fuming you may get one after developing the new image. The ghost isn’t from a latent image in the ordinary sense, in that it is usually a negative shadow, perhaps due to traces of mercury or surface roughness on the plate, either of which can interfere with subsequent fuming.

Mercury on the silver surface or residual roughness from the previous image can make the silver more reactive to the halide fumes, imprinting the plate with a pattern of thicker silver halide in the highlight areas of the previous image, which may make them slightly less photosensitive.

Ken used to advise “burning the plate” which involves heating the plate on a hot plate to 350F for a period of time to evaporate any traces of mercury. If you do this always do it outdoors.

[Pobboravsky]

Ken, Ken, Ken, I was shocked to hear you would elect-to-plate your children!

Irv

[RonF]

Mercury- (re: the morality of destroying an image)

I understand your point about destroying any daguerreotype image, however compromised to begin with. I bought two lots of plates (about 10 total) from a reputable dealer for the explicit purpose of reusing the plates. Some of them had images that were ok and I didn’t rub them out. Some of the plates had images that were barely visible, they had been rubbed out but not completely. I rubbed them out to use the plates. Sorry, but I simply do not feel that I did a huge crime. I was always aware that some people would feel that way. If they were photos of some significance, that significance is not significant if no one recognizes it. If a dealer with a good network can’t sell it for more than a few dollars then no one appreciates it. There were at least 10’s of million dags made and a lot survive. People always do things like unbind old books, or modify antique photos to make modern art out of them. There are always people who object to these activities. Hopefully the images destroyed represent a small part of the number of the surviving objects and would not be really appreciated anyways.

As the number of existing old dags decreases slowly; and the number on the market decreases as collectors hoard them, eventually no one would be able to buy a dag cheaper than a modern dag plate.

Would you say that someone should not throw out a 1990’s snapshot? Even if no one appreciates it and the owner does not want to store it? If so, where would you draw the line. I hate to see a decent image destroyed, but I am willing to make that call and I can still sleep at night.

For the majority of the ones I used, I was able to polish the plate and still have enough silver to make images, though some wore through to the copper at the edges during my first polishing. (I still use those).

Finally; you will be glad to know that I am not doing this anymore. I look forward to getting the polished copper plates that I ordered, and to try my hand in electroplating. I also have a piece of sterling I am going to try galvanizing.

If I get good at plating, perhaps I could sell the plates cheaply enough that no one could ever locate an old image cheaper than the cost of one of my plates. (I’m not promising anything here, I know it may be tricky).

…And if someone had a boy and a girl they could name her Cathode and name him Anode. I’m not even going to start a list of possible puns here, but I enjoyed yours.

[Mercury]

RonF, I apologize. No fault, no foul. Certainly no crime. I should have recognized that re-use of antique plates might not be a topic to make a casual comment on at first meeting. I’m glad that you’ve had success with them, my success rate was always less than good.

Also, I have spent too much time working in museums, where one daren’t mention such things at all. I learned that the hard way.

Your points are all good and well-taken. It is my personal opinion vis-a-vis successful daguerreeotyping, but I realize on re-reading that it was not said well. Again, I apologize, I did not mean to offend you.

… regarding the puns, I know at least one other avid reader of this blog that would also welcome you to start with your list! I’m afraid the rest, however, would get the keymasters to banish us for ever. Let’s start an alternative daguerreian blog where you CAN’T post without punning!

Sincerely,

Ken

[RonF]

Ken-

No offense taken. This is a point that I had thought about before so I had a response in my head ready to rattle off.

It is all subjective and I can’t fault you for being very much in favor of preservation. I struggled with the issue at first but decided that what I was doing is ok, but that working with new plates is the way to go in the future. (At least it is for the most part, I still may come across pictures that are deteriorated enough that I may rub them out, but I am not seeking them too actively)

I am sorry if my statement about not losing sleep over it may have been overly-defensive and perhaps that was what made you think I was offended.

I received my new plates (copper etching plates) and I can’t wait until I have the time to try plating them and using them. There will be the advantages of consistency (if I do it right), preservation, and I can’t wait to do something bigger than a 1/6 plate!

To end on a high note; I want to repeat how thrilled I am that this forum exists where people with shared interests take the time to give such thoughtful replies.

– Ron

[Festus]

Wow! Great discussion. I’m just glad all my plates are new!

Thanks for the advise guys.

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