Safety

There really are safety concerns, when working with ceramics. If the slip were only clay, it would be a whole other situation but the fact is, it's more than just mixed clays.

The dangerous part is called sodium silicate. It literally means liquid glass and that's not good for your lungs. Anytime, you're going to be working around the clay dust (even on the floor), wear a mask. I know it's annoying but you really need to protect your lungs. As long as you're only working with the wet clay, it's ok to unmask. It's the dust that you can breathe in, that causes the problem.

There are other safety concerns, that concern the government of the U.S., also. To stay within legal boundaries, make sure all mug,cup and pitcher handles are solid and not hollow. Also, never used leaded glazes on food containers, where any warm foods will ever be stored. Warm liquids, leach out the lead and can cause lead poisoning.

The commercial manufacturers of the glazes, tint the glazes different colors, so that you won't make a mistake and pick up the wrong one. Usually the leaded is a blue color and the unleaded a pink or green.

Never let small children in the kiln room while the kiln is running, for obvious reasons. Even if they are well trained, one stumble and you'll be sorry forever.

Remember that when that kiln is running, it's hot inside. Don't make the mistake of hovering over the lid, while peeking, once the kiln is running on high. It's not just hot, it's obviously a vast difference from the room temp and will blast. Be careful that your kiln gloves haven't developed a hole anywhere.

Just be safe, while working with clay dust and heat. It's supposed to be fun, not a trip to the hospital.

Non-Leaded Clear Glaze

I've fired many hundreds of dinnerware items, with the non-leaded glaze. While it's best to practically slop on the glaze, it's also very easy to get too much or puddling.

Puddling of the glaze will cause a cloudy appearance. If after firing, you find areas that are cloudy, this is due to thicker glaze in that area. It didn't completely melt. Your best bet is to try firing again, giving the piece plenty of room so that there is even heat all around.

Sometimes, you've simply added too much glaze and there's nothing you can do to save the piece.

Learn to add your glaze, 3 layers thick, very evenly without puddling. It takes practise and getting to know the glaze.

Areas where a drip formed, can be drimmeled off, add another thin layer of glaze and refire.

Hints About Firing Colors and Crystals

Odd things happen, when you're firing colors such as reds and greens. Get them too close to another object, and not only do you get grey faded areas on the red or green object, you also get funny shadowing on the neighboring objects.

Keep your red and green glazed objects, at least 6" away from all others on the shelf. It's best to put all the reds on a shelf by themselves.

As for those grey spots on the red glazed objects-these are caused by hot spots. When you put two pieces too close to one another, it causes the two almost touching, to get hotter where they are close together. At those spots, you will note grey areas on your red (and sometimes the green) glaze. This is the main reason for keeping those colors far apart from one another. Another reason is transference of color.

For crystal glazes, one must be careful not to have crystals overhanging another object in the kiln. Sometimes those crystals will run and drip down on the shelf (or worse, another object on the shelf).

Glazes tend to run, so it's wise to use less coverage, close to the bottom of your piece.