WarmGlass.com

I want to make a complex wafer. I need to have the design somehow on the shelf , so that I shall have borders and an outline.

Is it possible to draw it on the shelf with a pencil, fill the design with powder , and fire it? [the shelf will be covered with kiln wash]
Will the pencil marks on the shelf disappear with the firing?

I am aware that the powder will shrink when fired, I shall deal with it while drawing on the shelf [on the kilnwashed shelf]

I 'd be very grateful for your input!

many thanks,

Havi

Pencils are made with graphite, which is carbon (a glass separator). Chances are the carbon will burn out. The big deal is to not scrape off all the kilnwash with the pencil. As long as there is some left, I don't foresee a problem.

I use dry powder on kilnshelf for texture etc. often... I have not experienced any shrinkage when fired. Powder of course is reusable.

Bert Weiss wrote:Pencils are made with graphite, which is carbon (a glass separator). Chances are the carbon will burn out. The big deal is to not scrape off all the kilnwash with the pencil. As long as there is some left, I don't foresee a problem.

Bert,
Thanks,
Will it be preferable then, to draw with a marker??? I know that markers are burnt off from glass.


Many thanks,
HaVi

DonMcClennen wrote:I use dry powder on kilnshelf for texture etc. often... I have not experienced any shrinkage when fired. Powder of course is reusable.

Thanks, Don
Do you mean dry powder - as non liquid KILN WASH??
Will it not stick to the wafer?
I know from experience that the wafer shrinks A LOT on a shelf kiln-washed with liquid . Also, perhaps you would want to read the discussion in my previous post here, WAFFERS, where someone else also mentioned 30% shrinkage of the wafer.

This VERY interesting...........

thanks,

H.

If you write on a kiln shelf with a pencil, the pencil marks will survive the firing. (It's a good way to mark pieces as to ownership in a classroom environment.) The graphite wouldn't normally stick to the glass.

If you write with a Sharpie, it may or may not burn off. And it may or may not stick to the glass.

So, to answer your original question, it is possible to write on a kilnwashed shelf with pencil, use powder, and then fire. The marks won't disappear, but they shouldn't cause a problem with the piece. If in doubt, do a small test!

Thanks, Brad

I hope I can do both experiments on the same shelf, AND try what Don said on my other question, working with powdered shelf primer, instead of liquid - which might or might not prevent shrinkage of the glass powder - that is, if I understood him correctly.

Being that it is night here, hopefully by tomorrow morning, I'll have answers from all the directions

HaVi

I know wafers always shrink .. I misread your message and thought you meant the dry kilnwash was shrinking.( which of course it doesn't)..... I find with glass wafers you can control/reduce shrinkage by closely monitoring and shut down and crash cool as soon as light fusing occurs.

So the wafer will shrink.................
OK, made some BIG images, then they'll become a bit smaller, hopefully it will be OK.

Thanks for the input anyway, I am experimenting with primer powder, we'll see what that yields.

Good night [1am here]

H.

I've been following Havi's other thread about wafers, and all the informative replies, with much interest but am confused now.

1. If Havi draws on the kiln shelf with a pencil to outline her design, then uses powder e.g alumina hydrate, over the design before sifting on the glass powder won't the design disappear before the glass is placed? Wouldn't she have to use a wash?

2. On the subject of AH, which is my preferred seperator, here's a thread that raises an unanswered question.....Anyone?

http://www.potters.org/subject00470.htm

Jen

Hmmm. I draw on my shelves with pencil quite often and it never survives the firing. Granted, I'm using fine mechanical pencils, but I assumed they were graphite.

I also tried a technique once that I'd read about, where you draw on Thinfire with pencil, place glass on top, and full fuse. The idea was that the pencil drawing would transfer to the glass, but that didn't happen in my case.

Buttercup wrote:1. If Havi draws on the kiln shelf with a pencil to outline her design, then uses powder e.g alumina hydrate, over the design before sifting on the glass powder won't the design disappear before the glass is placed? Wouldn't she have to use a wash?

My assumption is that Havi is kiln washing the shelf, then drawing with a pencil, then using powder for her design. In my experience the graphite line on the shelf remains after the firing (I used an old-fashioned yellow #2 pencil, don't know about a fancy mechanical one.).

Buttercup wrote:2. On the subject of AH, which is my preferred separator, here's a thread that raises an unanswered question.....Anyone?

http://www.potters.org/subject00470.htm

Paragon warns in their kiln manuals not to get alumina hydrate on the elements because it will "ruin the heating element." They also say the same about getting kiln wash, glass separator, glass, enameling powder, or ceramic glaze on the elements-- they don't say not to use them, just not to get them on the elements. That's probably true, but I have gotten glass stuck to an element and had the element last for years afterwards, so it's not always so.

Thanks, Brad. Jen

(The post seemed to warn about simply having AH in the kiln. I certainly wouldn't want to get anything on the elements. That said, I've just bought a small, used enamelling kiln and it has a bit of glass stuck on the element but seems to heat up OK. Haven't really tried it out yet.)

If you use a soft pencil -- 2B or preferably softer -- it should be less likely to disturb the dried kiln wash. But then, I love soft pencils.

I have been using a powder mixture containing AH in my kilns for over 20yrs. I have to scoop it up off kiln floor regularly after it spills over the kiln shelf. I'm sure a small amount has found it's way (dusting) onto the elements over time. The kilns 20yrs and 13 yrs old have shown no ill effects. I sometimes think the alarmist make a case for a big deal over something much less so!

Thanks to all of you guys and your illuminating input. As I always say, I owe YOU, more than anybody else. I bless God that I can communicate in English well enough to be able to learn from you. This is not self understood.

So. I work with wafers - attempting to make components which I can combine to a whole piece.
Working this way frees me of worries what if this does not come out the way I wanted it . I can always reject pieces and/or correct them before including them in the whole composition. Which will then be fused to a sheet of glass.

I have not yet learnt the exact quantity of powder which I need, for the wafer to come out strong, sometimes it is too fragile.
I do not use sheets or parts of sheets.

I do free forms , so there is no need for me to go exact.
But sometimes I have in my mind a certain image which I want - and I need some outline of what it is going to be. Brad actually figured out the way I work and how I want things to develop.

I tried to use AH , on top of kiln washed shelf, on which I drew with a pencil - I drew on the AH powder, then sifted the glass powder almost on the same lines.

The pencil marks are not seen on the shelf. However, there is some insignificant [for me] mark on the back of what was glass powder and now is a wafer.

Perhaps I sifted too much AH - I do not like the results, and I shall stick to my usual method - i.e. wet kiln wash.
The AH powder stuck to the wafer, part of it I could wash away, but little stayed on the wafer. I might try soak it in vinegar to take the rest off.
I think that in this situation I should probably use a screen for the image, or make a stencil. Making a stencil is sometimes complex, for one single image.
I have not yet tried using a screen, but I hope it will be easier. I am taking a class in Europe next month, where I shall learn how to use the screen [ironically I AM a printmaker, but I worked with other techniques, not silk screening...]

Thanks again for the open professional discussion,
Havi

Can anybody who works with powder - AH, explain why he/she prefers working this way???
THanks

Hi Havi,

More adventures with wafers. I don't see any reason why you cannot mark the kiln wash on the shelf with pencil prior to sifting on powder. A statement of the obvious... draw your pattern backwards because the wafer will be flipped over.

You have a concern about thickness... I suggest going for about 1.5mm thickness and use a large sifter... the kind for steeping tea in a pot as opposed to a mug. They are about 10cm across. Keep the sifter over half full. If you are making large wafers then you might want to fire them slightly hotter.... closer to 718ºC as opposed to 696ºC. They will be stronger... but there may be more shrinkage.

Hope this helps.

Cheers,

Bob

Don, I agree.

Havi, I haven't used powder or frit on top of AH as I'm sure it would become incorporated. A smooth kiln-washed shelf is all I've used in my very limited experience with frit. I like AH for painting. The maturing temp. is not hot enough to melt the glass into the AH.Jen

Buttercup wrote:Don, I agree.

Havi, I haven't used powder or frit on top of AH as I'm sure it would become incorporated. A smooth kiln-washed shelf is all I've used in my very limited experience with frit. I like AH for painting. The maturing temp. is not hot enough to melt the glass into the AH.Jen

Yes it did, it became incorporated with the wafer................ like I said - I'll try remove this by soaking in vinegar, or use some staff against stones in the shower [know what I mean?]

Thanks!
H.

Bob wrote:Hi Havi,

More adventures with wafers. I don't see any reason why you cannot mark the kiln wash on the shelf with pencil prior to sifting on powder. A statement of the obvious... draw your pattern backwards because the wafer will be flipped over.

You have a concern about thickness... I suggest going for about 1.5mm thickness and use a large sifter... the kind for steeping tea in a pot as opposed to a mug. They are about 10cm across. Keep the sifter over half full. If you are making large wafers then you might want to fire them slightly hotter.... closer to 718ºC as opposed to 696ºC. They will be stronger... but there may be more shrinkage.

Hope this helps.

Cheers,

Bob

Thanks Bob,
A special thank for bothering to send me everything in metrical measures!
For others on the board - even though I am grateful for the metric measurements, please do not hesitate to send yours, as I can work on translations.
H.
Please Check the photo's I am think of posting of staff I made by now

Thanks again,
HaVi