blackthorn
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Posts posted by blackthorn
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4 hours ago, PeterH said:
Considerably surpasses it in ingenuity.
<insert blush emoji here>
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8 hours ago, Callie Beller Diesel said:
Those are turning out amazing!
I wonder if you could build up more detail if you layer multiple images.
Thank you Callie! Absolutely! I've been using multiple colors and have in mind to create a 3 or 4-color separation of the attached. Keeping the slab moist without blurring existing image content is the trick.
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Short version here, although I'm working on a detailed How To.
I'm printing on acetate, which is completely resistant to ink absorption. Dusting 50/50 Mason Stain/ Gerstley Borate or Mason Stain/Frit 3124 through a screen onto the wet ink.
Tapping and blowing off the excess and applying to a semi-moist slab. Carefully burnishing by hand, occasionally lifting a corner to check progress. Repeating burnishing as necessary.
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After seeing the shortcomings of Cyanotype on clay at high temperatures, I've been casting about for another (non-toxic) way to get continuous tone imagery onto the ceramic surface. I've been fiddling with dusting inkjet outputs with oxides or Mason Stain onto moister than leather hard slabs. Attached are some recent results. The process still requires more contrast in the working images than I want to end up with but it's getting close. They don't photograph particularly well since they change considerably with the viewing angle. I like the 'relic' nature of them. Sometimes l leave them out in the wild for some adventurous soul to stumble upon with delight and/or wonder ( I hope).
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I was lucky enough to acquire a very decent homemade wheel and a Skutt kiln from a fellow potter who was moving and couldn't take it with him. Sadly I didn't have room enough for his homemade pug mill. I use the wheel just for trimming since my other wheel was the very opposite of free.
I'm still coin hunting so I can pay for the 220 wiring for the Skutt. Soon, though.
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I recall seeing this woman's extensive pursuit of additions to clay bodies. Plus I did buy her book. So, maybe this will have some useful information:
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Peter- I agree with your suspicion that the iodine will burn out. The iron from a typical cyanotype is tenuous enough in high fire, so my expectation is for it to vaporize.
Otherwise, I've been working with over exposing regular cyanotype to the point of solarization. It's an interesting look on bisque but I've yet to see how it will survive cone 10.
Today's test is below, and is my commentary on the past two years.
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I'm still chasing processes for imaging on clay and have come across another process. Much like standard cyanotype but uses Ferric Ammonium Oxalate instead of the Citrate form and, it subs Anhyrdrous Ferric Chloride instead of Potassium Ferricyanide. So far, still using Iron salts. However, after a lengthy exposure, it is developed with Potassium Iodide instead of plain water.
The fellow who introduced me to the process says the Iodine seems to replace the Iron, which is not an encouraging outcome for my purposes in firing. I'm going to test it anyway, but meanwhile, I'm wondering if any here have ever used Iodine in any formulas. Other than medically of course.
I've attached an example of my comrade's process on glass.
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Been a while since I was able to squeeze one of these into a firing.
Here's the latest test. Exposing the cyanotype twice is helping keep the image from fading so much.
Next step is spraying a clear glaze over it to see if that will keep the image from evaporating during Cone 10 firing. Leda is just so so and the swan is fading, so I also think a less contrasty negative and a third exposure to build up the iron. We'll see.
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A belated posting on this topic.
Before and after of cyanotype on bisque - and re-bisqued.
My next test will be reprinting and re-firing, however many times needed to get the iron to build up into a less subtle image.
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From what I found in my research on slumping glass onto ceramic substrates:
Fire the kiln to a temperature between 1200 to 1300°F (648.9 to 704.4°C), keeping an eye on the glass through the peephole.
The glass will begin softening and turn glossy when the temperature nears 1000°F (537.7°C) and start slumping as it nears 1200°F (648.9°C).
Sadly, I think this is much higher that the silver in Liquid Light can endure but have yet to confirm this. It will likely dissapate above 1000ºF.
It's on my list to test but will require dedicated kiln time at the school and we're in the middle of a term with students scrambling like ferrets to have their work fired.
Still, sounds interesting and I'll pursue it as time permits.
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9 hours ago, PeterH said:
1) The cyanotype process precipitates out a strongly coloured iron compound, which forms a strong image. If fired this will decompose to a paler iron oxide. Here are some pix of the unfired image. I've yet to see any pix of fired image. https://tinyurl.com/8ubba93x
2) Legalistic quibble. The initial cyanotype process was a liquid process and relied on the backing material (paper,cloth, etc) to hold the precipitated compound in place. This carries over naturally to porous ceramic but not to water-proof glass/glaze.
3) A long-standing solution to this problem is the precipitate the iron compound into a layer of gelatin or similar. https://tinyurl.com/ynhzneer
4) If you want a fired-on image from such cyanotype I would just try firing them. The situation is not that different from transfers or gum-DAS images so the chances of it working are promising.
5) Do we know anybody who has tried this? How successful was the attempt?
@PeterH To your points 1 and 5 - I posted images of some of my recent tests earlier in this thread. To your point 2 - I've found this to be true of fully vitrified stoneware and porcelain, so I coated it with a combination of equal parts of Whiting, Gesso and water. It remains stable long enough to allow for exposure, processing and firing if it done within a day or two. I haven't tried it yet but I'm also going to spray paint flat white, sand and repeat a few times, on a fully fired slab to see if it allows cyanotype to not bead up. Gum or gelatin will bond to the painted and sanded surface.
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2 minutes ago, jsmoove said:
I think im confused about the pigment part. How do we know what pigments survive the heat?
Reading just about any book on Ceramics will provide info on pigments that are used, and the better ones will describe the behavior of most at varying temperatures.
Since we know that:
"Glass melting is performed at temperatures between 700°C and 800 °C which correspond to an optimized value of the viscosity for glass refining and shaping",
we can surmise that firing an exposed and processed sheet of glass will begin to flux at temps nearing that. Experimentation would be essential to see 1) How high is high enough to completely bond with the surface image; 2) How high is too high, which would result in partial or complete distortion of the image, ala Salvador Dali; 3) If it's even possible to sufficiently melt the glass without it bonding to whatever cookie or shelving it's resting on during the firing.
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I purchased my supply of Potassium Dichromate from Bostick and Sullivan but a quick Google search will turn a dozen more places, like another of my favorites: The Photographer's Formulary. Here's a link to Bostick and Sullivan:
https://www.bostick-sullivan.com/cart/3/109/
Yes, it's toxic. Maybe more so than Cobalt and perhaps Barium but handle with good and sensible care and you'll be ok.
ps. Some low fire glazes actually call for Potassium Dichro. Just saying.
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8 hours ago, PeterH said:
I cannot think of any reason why iron oxide cannot be used as the "pigment" in gum-dichromatic style processes. Or any other photographic process with a wash-away binder carrying a pigment. Wouldn't keep banging on about it otherwise.
[Or ceramic stains with or without a binder; eg frit or "Gerstley borate"].
Absolutely Peter. Iron, Cobalt, Manganese all can be and are used as pigment in gelatin or gum dichro printing.
The ONLY thing one has to watch out for it the amount used. I can attest to the fact that if too much of any of these is used then the emulsion becomes to opaque, like parts of the negative and blocks the exposure. So much of the emulsion simply washes away after exposure. Less is more with both oxides and Mason Stains and interestingly enough, that includes Mason Stain White, which I've used with film positives on dark clay bodies, instead of a film negative.
But, @jsmoove, your point about testing is, of course, correct. I'm still doing that. I've found many ways how not to make these processes work.
I have no experience with glass work but admire the process. There are only so many hours for me and that's another rabbit hole in which I could easily get lost.
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Mark's comment on eating Fair food and getting ill reminded me of the time I got food poisoning and my wife had to do the tear down and packing all by herself as I writhed, sweating in agony. Subsequently I planned my fasts around events and just drank tea and water. Two or three days was not a struggle. Not a very exciting response to the original question I suppose but there it is. I'm extremely unlikely to eat street vendor food from any location ever again.
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11 hours ago, PeterH said:
"I've no idea if hardened (cross-linked?) gelatin melts. If it does it might be worth trying the gum arabic form the gum-dichromate process instead."
The gelatin melts at kitchen cooking temperature and burns out completely by bisque temps, regardless of whether it's hardened or not. I use glycol as a hardener when needed. It's also organic and vaporizes along with the gelatin.
As for the reason for using gelatin vs. gum arabic - if you want to lift and manipulate the image off its original substrate then gelatin is the choice material. Gums, both Arabic and CMC are proper for creating the image directly on its final surface. In the long tall image I posted above (Liber Novus Liber Novus Gum Bichromate) I used Gum Arabic.
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Ok. Like you, one of my goals is to create an absolute permanent image, and, as it happens for my part, to make it on ceramic. While I like the cyanotype process, my next project involves the other video link I posted - Carbon Transfer. What I'm doing is creating the emulsion of Potassium Dichromate, Mason Stain and Gelatin. I pour that on Yupo and let it dry in full dark. After dry, I get the enlarged negative of choice and expose it. I've also prepared a bisqued slab coated with a mix of gesso and Whiting which is then coated with gelatin and hardener. The exposed Yupo/gelatin substrate is sandwiched with that slab and set in a tray of hot water until the gelatin releases from the Yupo and adheres to the slab. Yupo is peeled away and washing continues melting away all the unexposed gelatin leaving the exposed (hardened) image. Now it's such a thin coat of gelatin that during firing, as it melts, the actual image suffers minimal distortion. One down side is getting an image onto something thrown or more dimensional than a slab. Of course the absolute major challenge is to find an image that integrates into that form and not just having an image on it for the sake of having an image. I'll post an image of then when successful.
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2 hours ago, Min said:
@blackthorn, your ^10 cyanotype + white underglaze looks like fossil dug up from an excavation. Neat stuff! Thanks for sharing your process and results.
Thank you Min! It's actually in my front yard pretending to be just that, along with some fossils I made just for that purpose.
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As for the cyanide gas release during the firing, yes, the kiln is outdoors and well away from any human traffic. Even so, the amount of hydrogen cyanide is really quite small given the coverage of the pieces you see above.
As you say, you want to render your image permanent on the glass. Firing is both unnecessary and most likely ruinous. In order to use glass as an initial substrate like the fellow in the link below the glass has to be of reasonable thickness to allow for handling as well as support of the image. That would make it at the very least 1/16th of in inch thick. Regardless of how the image is affixed to the glass when is fired that image will most likely go all Salvador Dali and become unrecognizable. Could be interesting but it's a grand toss up.
As you mentioned wanting to commit your artwork to glass specifically, so here are some links to two fellows doing just that. Keep in mind that their works are finished pieces and would never survive a firing at any temp. And your point about the Liquid Light is true, given the melting point of Silver Nitrate is something you can accomplish in your household oven, right around 450º F.
There are a few ways to render a permanent image on high or low fired ceramic surface but to the very best of my knowledge they don't involve an initial glass substrate. Then again, I could be wrong.
Here are ways to render images on glass pretty permanently - without firing:
Cyanotype on glass:
Carbon Transfer Printing on Glass:
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@jsmoove
My background is also in photography and my projects of late have revolved around getting a stable photographic image on ^10 ceramics. I've not tried any glass work but am having plenty of success with a handful of techniques, most of which involve direct contact exposure with a large format negative.I've previously posted a few imageson the forum here so won't take up additional space re-posting those but the ones here are more recent takes on the two most successful techniques: cyanotype and gum bichromate.
Cyanotype is lovely, both unfired and fired. Although it's main light sensitive constituent is iron, the iron is fugitive at higher temps. I've not yet tested it's high limit but at bisque it comes off a nice toasty brown.
The gum bichromate is just like the paper print process though instead of watercolor pigment typically used, I mix mason stains or Manganese Dioxide with either Gerstley Borate, Frit 3124 or some clear glaze recipe as a binder.
So far all of my tests are on slabs but I'm constructing an exposure unit that will allow for 360 degree exposure for taller thrown work.
I know it's a bit off topic from the ground glass rod query in the op but it does speak to the process of fixing true photographic images onto a ceramic substrate.
There are a couple of other processes I'm exploring but the results have been a bit weak so far, but still have some possibilities. Happy to discuss if you're interested.
- Min, Callie Beller Diesel and jsmoove
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3
Making a photosensitive powder
in Clay and Glaze Chemistry
Posted
The next test will be using cling wrap fastened securely to a substantially supportive substrate.
Printing then dusting that.
Unfastening the cling wrap and transferring the image to one of my thrown forms, taking advantage of its incredible flexibility.