Thursday, December 6, 2012

glazing green-wear? please help

I'm making cupcake stands with my 6/7th grade class... it has been a slow, less than ideal lesson that will need major work before I do it again. It has taken us so long to build them that I am really crunched for time on firing the green-wear and then glaze firing before winter break and there is no way I am letting this lesson drag on after the break.
I have always been told NOT to apply glaze to green-wear and fire it for several reasons that I fully  understand but I basically have no choice this time.

So my question is: have you ever glazed green-wear and then successfully fired it (low fire) any suggestions or tips that you can pass along to me so I don't turn this blah clay lesson into an epic disaster of a firing?

p.s. we do use ducan this case we will be using the sprinkle series and I always have the kids add a layer of clear coat


  1. It turns out okay on slabs and pots, just don't put wet glaze on joined pieces or they will pop apart before you can get them in the kiln. Good luck!

  2. I have glazed green-wear fact I'm having the kids do it right now on their checkerboards so that we can get those out for Christmas as well! I've never really had a college we would under glaze our project before bisque firing them as well (granted, we were using homemade glazes and such). The only thing is that you should remind your students to be really careful handling their unfired clay project...setting it down on the table can make it snap!

    Also, after they are fired, I've noticed that the underglaze sometimes will still wipe off, so be careful with that. (I use Amaco underglaze...maybe it's an Amaco thing?)

  3. Yes I have.

    Keep the glaze thin and be sure it is applied quickly. Too much and the piece could sag on you.

    I'm not familiar with Ducan (I use AMACO) but do you have a piece or two you can do a quick test run with? Just to see what will happen.

  4. I know exactly what you are talking about. I have also had to glaze greenware and fire it before. The biggest issue I have found is that the glaze doesn't always like to paint smoothly and evenly. All you can do is tell them to paint carefully and try to paint them evenly. Otherwise the pieces usually look just fine.

  5. I've done it before. The biggest problem I have run into is that it is easily breakable. Just have your students be extremely careful. I have always just used regular low fire glazes, I have never done underglazes, but I imagine it would work out the sam.

  6. At my state convention, they told us to leave some part of the greenware unglazed to allow for expansion during firing.

    Good luck!

  7. Sometimes, applying the underglaze to greenware is the best option. But, most underglazes have a chalky finish which is not an ideal end product. Therefore you must glaze the piece or in other words, give the piece a shiny coating.
    There are some products on the market that are a 2-in-1 product meaning underglaze and glaze. Maco stroke and coat is one of them (I think).
    Alternately, if you only have time for one firing, fire the greenware and then use acrylic paints to color the bisque. Easy!