Tuesday, 16 December 2008

Finished Pieces and The Creative Roller Coaster

I couldn't sleep at all last night; my head was buzzing with new and exciting ideas. I was almost tempted to get up and start working on them straight away!

I left home to collect my fired pieces tonight in a good mood. I had a few questions to ask the tutor as well. I was interested to know why some ceramic pieces crack in cold weather and some don't - apparently it's to do with the moisture content in the piece, so the problem can be solved by using stoneware (which is water tight even without glaze) rather than earthenware (which is quite porous), and firing at a reasonably high temperature. (Please correct me if I've got a little bit muddled - my tutor doesn't always explain things very well)

I was also interested to know why he fires specifically at 1220c every time, when there is a range of temperatures suitable for the clay and glazes. He said that he had found 1220 was the optimum temperature for the glazes that we use at class. I beg to differ, seeing as I have used the cream glaze twice now (on my little head and also on the "Yes I Can" mug) and both times it has left a bubbled surface. So I have a "Yes I Can" mug with a finish that says "No I Can't". *Rolls her eyes*

He said he buys a clear glaze and adds other ingredients for the colours. The top firing range for the clear glaze is 1220. Common sense tells me that one should fire slightly lower than the top temperature to allow for temperature variations in the kiln, and I also know that adding other ingredients can alter the temperature at which a glaze vitrifies.

Talking of temperature variations in the kiln, this plate and mug were fired in the hottest part of the kiln, and the lovely brown colour that I was expecting has turned into this awful green, which proves my point about not firing at the maximum temperature really. (I'm not sure if the colour shows very well in the photo, but trust me, it's awful) I'm sure he wouldn't do anything as stupid as that with his own pieces.

The plate had warped really badly. The tutor said it could be my clay, as I don't know what the firing temperature for it is, or because the plate needed to be thicker. Oh well, it's a learning curve. How do other people make thin plates without them warping?

I've been looking at other glazes recently and asked my tutor if I could use my own, but he said he wouldn't fire the pieces because it's "too risky". Personally, I don't see what the risk is - if the temperature is within the firing range then what's the problem? And we've already proved that glaze run issues can be overcome.

So once again I feel like my progress is being hindered. It is so frustrating. I just want to learn and progress and improve.

The only pieces I was reasonably happy with tonight were the ones I had least expectation of - my roasting dishes. The small one (light green - achieved by using white glaze first and then green) is a bit patchy, but like I said, I had some trouble glazing it - the glaze was rubbing off in other areas when I was trying to clean the bottom. At least I can have some toad in the hole now!

These have warped slightly in the middle too. I'm guessing that it's because of the quality of the clay at class?

Has anyone else had problems with glazes bubbling? Is it because of the temperature? Actually, has anyone else had these problems with tutors?


queencraftygirl said...

Love the 'Yes I Can' mug! Something to drink out of when you need encouragement! :) The flower mug is so neat! the white flowers turned out really pretty!


Undaunted said...

Thank you so much Queeny! You are so encouraging!

Yes, now that I am (kind of) getting used to the colour of the flower mug I suppose it's not so bad. I do quite like the flowers. I'm far too grumpy aren't I? :)

queencraftygirl said...

Once at one of her shows,
Aunt Leanne (paintergirl) had tried a new glaze on one of her little bird rattles. (She thought it looked ugly) She laid it down one of her slhelves and wasn't planning on selling it. One lady found it and wanted to buy it.

See, I like your mug. Maybe you will never completely like it but if someone else likes it you will learn to like it yourself. You aren't grumpy, you are just not satisfied. :)


Undaunted said...

Oh Queeny, you have such a wise old head on your young shoulders! You're completely right of course. I'm not happy with it because I know it doesn't look how it was supposed to look, but other people don't know how it was supposed to look so they have no expectations to be fulfilled.

Thank you Wise Queeny! :)

Leanne Pizio said...

Oh My!
My niece is wise! Wiser than her Aunt Leanne that is for sure and I completely agree with her. I so love the mug with the flowers. I was so amazed when I saw how it turned out. And the Yes I can mug is wonderful as well. Though I know how it feels to be disappointed by glazing....boy do I know how that feels....Queeny is right!
You never know how others will see that same piece that you find so horribly wrong.

Let's skype soon so we can talk about the warping and the bubbling of glazes. I think I can help a little bit with that.
As for the tutor, he just seems like an ass to me. (excuse my language please Queeny girl.)

Undaunted said...

Thank you Leanne! I'm glad you liked the mug too.

I tried emailing you about skyping today - I hope you got it!

I have news about the tutor thing...

queencraftygirl said...

Thank you both!! :)