Post #593222 by swizzle on Sat, Jun 11, 2011 1:21 AM

Thanks Wendy. That crackle effect is not actually a feature of that particular glaze. I think it just happened as the mug was cracking. The other mug was fine until I reglazed it and that one did it then also (see below).

This week I picked up a few more of my mugs which will be going to friends and really are just for me to experiment with colours and to get my head around glazing.

This first mug will stay in my collection as it's the first mug poured from the new mold I made after I resculpted the master. It also has additional woodgrain carved into. Initially I tried to use a brown oxide on this mug which was to be applied and then wiped back to leave the colour in all the crevices, but I wasn't happy with how it turned out so I glazed over it with the brown used on the inside of the mug. After it had been fired I felt the finish was too patchy so I glazed over it again, this time with a lead based glazed called "Crackle Goldene" which should have come out literally a dark gold like colour, but it didn't. I'm still quite happy with the result though.

This mug is going to one of my oldest and dearest friends. This mug was also reglazed as the finish was too patchy for my liking. Although it still is a little bit, it certainly looks much better. Royal Blue exterior with Oyster White Speckle interior.

This mug has gone to a good friend who is the brand ambassador for Appletons Estate rum here in Melbourne, Aus. Although it had three coats of glaze on it, it still came out patchy (like the others) where the bush strokes are noticable. He, and another friend who saw it both like the finish and both said the same thing, it makes the mug look handmade, which I take as a compliment. This is the closest colour we had at school to red (his favourite colour) without using a lead based glaze. Burgendy exterior with Mist Green interior.

This last mug is another that I reglazed as I wasn't happy with the result, although that was more so because it didn't seem to come out the same colour as the mug I had glazed a few weeks earlier that cracked (page 4). Peacock Green exterior with Apple Green interior.

However, guess what happened?

:( That's two mugs that have cracked using the same green glaze. Originally I thought that the first mug cracked because the glaze on the inside was quite thick but this mug had only one coat on the inside and the same thing happened, although not as bad, yet it is still unusable. It was fine after the first glaze firing and only did this after I gave it another couple of coats, a total of four. I spoke to one of the other teachers at school and they said another student had made a huge vase and glazed it with the same colour and that cracked also. I rang the manufacturer and explained the situation and they said that they had never had any problems with that glaze before and that it must have been the clay body I was using, however that doesn't explain the other students vase which would have definitely been a different clay. They also said that there must also be some sort of tension issue going on with that glaze and the others used on the interior (a different brand) and that I should try using just that glaze on its own, but thats quite useless to me if I want to make a two-tone coloured mug. I'm really quite pissed off as it's a beautiful colour and I have two mugs to make for people who both want green but i'm reluctant to use it again as I don't want to waste my time if this is going to happen again. We have an Italian Green at school which is slightly darker and a different shade, but still quite nice so I think i'll give that a go instead. Fingers crossed that will be OK.

That's all at the moment. I have glazed another two mugs which are ready to be fired. Hopefully they'll be ready next week.

Cheers
swizzle

[ Edited by: swizzle 2011-06-11 03:28 ]

[ Edited by: swizzle 2011-06-11 03:32 ]