Glaze prettier inside cups and jars

Yes, I have. If a piece is dipped I don't think it would be thickness. I have a feeling it has something to do with heat and/or air circulation. I just made my first test batch of Waterfall Brown from the book Mastering Cone 6 Glazes. The outside of one piece looked completely different from the inside of another. I wish I could duplicate the one on the inside. I like it a lot better. The inside one was a pot with a lid. I fired it with the lid on so it had basically no circulation. It probably cooled a lot slower, too. I'd be interested in hearing other's theories. Gaye

That's funny. I'm also mixing some of the glazes from "Mastering Cone 6". I haven't mixed the Waterfall Brown yet but I love that glaze in the book. We will have to start up another subject thread on the glazes in the book. I'ts been awhile since I've snuck around on this list. I will have to check for some recent discussion on that subject. Yes I have the same feeling and I would like to know how to correct it. Hopefully someone has the answers. It's nice to know I'm not alone on this. The ones that I'm talking about either had no lid or fired without the lid. I usually only bisque fire with lid on so that I can glaze the edges. I could see the glaze being thicker on the inside if there was a rim flaring in that would hold more glaze in when turned over, but I have some where the rims were either flared out or straight and they still look nicer on the inside.

I am trying to teach myself patience and use test tiles, but it's not working. I always test on actual pieces. I may start testing on bowls so I can try several glazes at once and, if they run, they'll run IN the bowl. Gaye

it has to do with more retained & reflected heat from the firing. if you can pack your kiln "really densly" you get similar results on the outside. if you can put your pieces into a sagar you'll also get similar results to the outside of pieces. break a vase open and you'll see beautigul inside glaze surfaces that you can't see without having broken the vase.

the piece is actually exposed to different levels of heat in the fire - the outside "seeing" different heat from the inside.

slow down the firing speed, slow down the cooling speed helps even out inside-to-outside glaze differences if you can control these aspects of the fire.

steve

steve graber

Ok, good idea. Let's go ahead and start the topic. Waterfall Brown is the only one I have tried so far. I overfired it so I can't really say too much, except it looks liek it can be overfired and still look pretty much like the photo. My suggestion would be to put it ona textured surface for a better result. Mine was on a smooth bowl. Gaye

Thanks Steve! The mystery is solved then. My kiln wasn't packed by any means, but it's sure something I'll keep in mind. Gaye

My kiln wasn't pack densely either. Well the space shelf space was used up but I tried to stagger tall and short items so there would be more circulation. Maybe I should try all items the same height on each shelf. I don't really have the ability to fire slower once I switch on high (electric kiln with kiln sitter) but I will try leaving the switch on medium longer. I only did a 15 minute soak and I did manually slow cool the batch. I stop the kiln from switching off by the sitter and switch it from high to medium for a couple hours then med/low. etc. Guess I will try readjusting my firing schedule and see what happens. Thanks, Crystal

I always thought, or was told by a teacher, that glaze always looks better on the inside of a cup because you normally pour this first and it gets a thicker coat than the outside. This is because the bisque body has absorbed water from the glaze and then will not absorb as much during the glazing of the outside...therefore making a slightly thinner coat.

I now do the outside of my mugs by dipping them down into a container of liquid glaze, wide and tall enough so as the mug will not hit the sides, up to the point where the glaze is even with the rim but not going into the cup. In this way you can glaze the whole exterior in one even coat. The longer you hold it down the thicker the glaze coat will be. Works nice.

If you glaze where the entire piece is immersed at once (using .... tongs... wrong word... thing with little pointy ends that clasps pot... help me here someone..) you can still get this effect but not to the same degree - maybe the effect is because glaze following gravity is going to just pool in the interior and not on the exterior giving the appearance of a thicker application? I was very surprised to find that you can get so much variance in an oxydation firing. I believe that our best firings were those with some time of soak. The interior of anything that was at all closed in would be similar to a firing with a soak. I also find when I pour into the inside, pour out, then dip that I am much slower at getting the inside glazed then the outside which would give as you say a much thicker coat on the inside than the out. Add to that glaze running on the inside and pooling in the bottom of the pot, the glaze moving down away from the lip, etc. then you have all sorts of varience going on.

Just some rambling thoughts here.

DKat

Great tip! Thanks

Glad you "rambled". You had some great thoughts.

Thanks everyone for all your comments. I will so some adjustments and see what happens on my next firing. I appreciate all of your replies. Crystal