Concerning firing enamels

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Havi
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Concerning firing enamels

Post by Havi »

Hello dear friends,
I hope you and yours are healthy and safe regarding the COVID 19
Recently I have been firing enamels... I printed leaves on the glass, then fired them.
I fired 1 piece on my smaller Paragon [17" octagonal] to 730C, 1346F The piece came OK as far as technique.
I fired 4 pieces on my Jen Ken squarish 24" again to 730C - and everything was burnt! Only tiny dots, which look like unrelevant dirt.
A friend here, saw the photos [before and after, I document everything] and suggested that the paint was too 'liquidy', not enough paint - therefore it burnt away..............
With broken heart I re-printed and refired tonight a more concise version of the ink, on the Paragon to 690C. 1274F It came out perfect!
now questions / dilemas
1. Can I refire the piece I made???
1.a. What would happen in I go to a higher degree on an additional firing - will it AGAIN, fire out the print? This has influence on my sequence of firing, i.e. the print should be the last firing?
2. If the paint I have applied is perhaps thin, can I, to be on the safe side, cover the whole piece with frit, 08, OR 01?
Then again up to what temprature,
or is the frit cover protecting the print from being totally burnt out???

I'd be more than grateful for your responses and expeiences, as always,
if possible , please do not tell me to TRY it, I know I can try, but perhaps someone out there has the answer without me trying again, I so hurt when failing....

another thing, actually my Paragon has an elements problem, it does not heat evenly, so I take the risk of firing only smaller pieces on the good side

So thanks again,
stay safe,
Havi
Haviva Z
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"Speed comes from the Devil" - (an Arabic proverb)
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Lynn Perry
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Location: East Tennessee

Re: Concerning firing enamels

Post by Lynn Perry »

Hi Havi. You seem to have several potential problems, the first being that you do not have an accurate known temperature in one of your kilns, the one where you had the best results. You did not specify what enamels you are using either, and the range you fired of about 125 degrees between the firings is definitely enough to see some differences in the result.

When you say you printed the leaves on the glass, does that mean you are not firing the leaves themselves? Also, I do not know why you need to cover the enamel with frit, unless you are using lead enamels and are trying to protect food from the enamel. Enamels generally give a nice shiny surface, unless you are using matt or transparent ones.

I think your friend is also correct about the liquid being too thin with too little enamel, so the result was not one uniform color. The liquid you used to make the paint can be a factor. Some liquids can hold much more enamel, and give a much more dense, uniform result. A14 holds much more enamel than Klyr-fire or water. I have not had any problems re-firing enamels, and you can always apply additional enamels to the areas which have already been fired. While enamels work well with most glasses, if the enamel layer gets too thick, COE problems can occur.

Given than this entire process can be finicky, you are going to have to do more experiments with reliable equipment which will give you repeatable results (sounds like chemistry class....). I greatly enjoy making enamel jewelry, which is totally different than just fused or dichroic glass and the possibilities are endless.
Lynn Perry
Havi
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Re: Concerning firing enamels

Post by Havi »

Many thanks Lynn.
Actually I am experimenting with COLORLINE printing paints / inks, which I have for several years now. Those inks are made by Creative Glass in Switzerland, where I took a class, and consequently bought some inks AND paints. [the inks are more concentrated than the paints]
However - I do not need to add any liquid. But the inks are old, sometimes a bit too dry, therefore I dilute them using some binder I bought in USA, also years ago...
so in a very non-American way [you Americans are perfectionists, probably would have discarded those inks.]
I try and see what happens. Before I do a REAL piece.
My dilema concerns the red ink I used, which seems to have been too diluted.
This is one of the reasons Why I turned to you - will adding frit solve the problem of diluted ink? Will it protect the ink from burning out?

We are now on a very tight lock down. So I can not get help from a kiln electrician. to check the controller and the thernocpule on my Jen Ken. The elements for the Paragon will reach Israel next week, but I am not sure the supplier will be able to install them - before the lock down ends. Between 2 - 3 weeks from now.
So I am doing what I can in this situation.
I have some Sunshine-Ferro enamels, which I am sure will work excellent. This would be my next experiment. I feel I need to have more experience with the technique, in order not to waste the better material.
Also, perhaps it is worth mentioning, that I do not do jewelry, bigger staff, aiming to even bigger compositions, so every unsuccesful project is a bigger loss of material

However,
I am gratful for your resonse, and applogiise for my too long answer - - -

Havi
Haviva Z
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"Speed comes from the Devil" - (an Arabic proverb)
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Lynn Perry
Posts: 128
Joined: Sun Jun 08, 2003 5:27 pm
Location: East Tennessee

Re: Concerning firing enamels

Post by Lynn Perry »

Hi Havi. What a pain the virus is, even without being infected! I now understand and appreciate what you are trying to do. For the red ink, I am fairly certain adding frit will not help much, if any. However, if you can leave the red ink open for a while or transfer it to a larger, more open container, wouldn't evaporation help concentrate the ink? Wishing you the best in all of your work and your health.

Lynn
Lynn Perry
Barry Kaiser
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Re: Concerning firing enamels

Post by Barry Kaiser »

As to burning out, that should not happen at all. It is possible that the pigment in the paint has decomposed. Do not trust the color of the unfired paint to indicate the final color.

Covering the paint has no benefit in retaining the color.

You should be able to paint and refire. The refiring only has to mature the paints. In the case of mine, you can fire to 1325-1350 F. You do not have to hold since the paint is on the surface.

As to the thickness of the paint, you need to determine that yourself. You can test a small sample. Our paints (and some others on the market) are formulated to work at a very thin layer. That is one of the major things that determine the quality of the paint.

Adding frit to the paint can be problematic. I might recommend adding flux (which is just ultra-fine frit). but even that is problematic because it can dilute the pigment in the paint to the point that you do not have good coverage. However, it may well work with a good quality paint.
Dianne Van de Carr
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Re: Concerning firing enamels

Post by Dianne Van de Carr »

My experience is that Colorline hot colors have to be fired separately. Paint the cool colors and fire. Then do the warm colors. Be sure to vent until 1000 degrees.
I hope this helps. If not, get Barry Kaiser’s enamels. They are foolproof!
Dianne
Havi
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Re: Concerning firing enamels

Post by Havi »

Thanks, Dianne
I love the idiom "foolproof" it is applicable for me.
I have a whole stock of colorline enamels at home, some of the are old and actually useless. Anyhow I'd like to buy powders - i assume they are safer to keep, in the long run.

Thanks for your imput about separating the blues from the reds, never was aware of it!

All the very best,

Havi
Haviva Z
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"Speed comes from the Devil" - (an Arabic proverb)
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JestersBaubles
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Re: Concerning firing enamels

Post by JestersBaubles »

Hello Ms. Havi,

I know with the Colorline enamels, the reds will burn out unless they are fired on their own. They are affected by a reduced oxygen environment so any organics in the kiln that are burning off will affect the color (including the binder in other enamels in the same firing) So, paint with the red first and fire. The kiln needs to be vented until about 1000 deg F / 540 deg C to increase oxygen. Once the reds are "set" in the first firing, they should be OK to fire with other colors. I usually avoid using them because I am lazy :)

With this piece below, there was a LOT more red in it, but all that remained were a few red/rusty streaks after firing (the red dots are frit). You thought all my work was perfect (ha ha) :mrgreen: I just try to make the best of it.
cobaltwave-small.jpg
Dana W.
Havi
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Re: Concerning firing enamels

Post by Havi »

Many thanks to all of you, who bothered to respond to my questions,
I allways learn something new, for which I am so grateful.

Dana , still sorry that i did'nt earlize it was YOU, when we met in Lybster.
As for colorline - I shall be very craeful using what I have of those colors. I might not buy new, I think its better to buy powders, which survive better.
\
Be safe all of you,
take a lot of vitamin D

thanks again,

havi
Haviva Z
- - - - with a smile :)

"Speed comes from the Devil" - (an Arabic proverb)
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http://www.havivaz.com
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