{"id":6771,"date":"2023-08-23T17:54:28","date_gmt":"2023-08-23T17:54:28","guid":{"rendered":"https:\/\/www.eltornbarcelona.com\/?p=6771"},"modified":"2026-04-08T09:12:10","modified_gmt":"2026-04-08T09:12:10","slug":"5-tips-glazing-pottery","status":"publish","type":"post","link":"https:\/\/www.eltornbarcelona.com\/en\/5-tips-glazing-pottery\/","title":{"rendered":"5 tips to be happy with your glazing process"},"content":{"rendered":"

\"Muestras<\/p>\n

5 tips to be happy with your glazing process<\/h2>\n

I hope you\u2019re doing well!<\/p>\n

This is the first post of the year. And this time, we\u2019re diving into something a bit more \u201ctechnical\u201d: glazing. Let\u2019s get into it.<\/p>\n

When we talk about glazing, we first need to understand what porosity is.<\/p>\n

Porosity refers to the ability of a solid material to absorb liquids, thanks to its microscopic pores. In the case of clay, this means that while it can hold water, it also absorbs it over time\u2014expanding and contracting as it dries.<\/p>\n

The risk of bacterial growth is the reason why ceramics intended for food use should not be porous.<\/p>\n

Let\u2019s talk about clay types. Red clay (low-fire clay) is particularly porous, making it extremely difficult to clean thoroughly. As a result, bacteria, mold and fungi can develop. Even if a piece looks clean, it may contain harmful toxins that can leach into food or liquids.<\/p>\n

Stoneware and porcelain (also known as high-fire clays) are considered non-porous when fired to 1285\u00baC, as the clay particles \u201cmelt\u201d and vitrify at this temperature, forming a glass-like surface.<\/p>\n

However, if you fire your stoneware or porcelain at a lower temperature, then\u2014just like earthenware\u2014you must glaze your pieces for them to be functional.<\/p>\n

Before diving into glazing, you might be wondering: are raku pieces functional?<\/p>\n

Raku typically uses high-fire clay with grog to withstand thermal shock. But despite the clay body, the process itself is low-temperature firing, meaning the clay does not vitrify. In other words, it is not food-safe.<\/p>\n

What about burnished ceramics?<\/p>\n

Burnishing involves polishing the clay surface to create a smooth, shiny finish. It\u2019s often used for decorative purposes. But to be food-safe, the piece must still be fired to 1285\u00baC. At lower temperatures, glazing is essential.<\/p>\n

Now that we\u2019ve cleared that up, let\u2019s get to the point: glazing.<\/p>\n

Here are our 5 tips to be happy with your glazing process.<\/p>\n

1. Take your time<\/h3>\n

For me, this is the most important tip\u2014and also the easiest to ignore when a deadline is approaching\u2026<\/p>\n

That \u201cI\u2019ll just glaze everything quickly\u201d approach almost never works.<\/p>\n

Give yourself time to go through each step calmly and consciously.<\/p>\n

2. Prepare your pieces properly before glazing<\/h3>\n

Avoid handling your pieces with dirty hands or after applying hand cream.<\/p>\n

Clean off any dust before glazing using a damp sponge. Oil or dust can act as a barrier, preventing the glaze from adhering properly and potentially causing it to run.<\/p>\n

Sharp edges should be sanded before glazing. Don\u2019t ignore this\u2014once glazed, there\u2019s no fixing it.<\/p>\n

It\u2019s best to develop the habit of checking this before the bisque firing, as it\u2019s much easier to work on edges at leather-hard stage.<\/p>\n

3. Let your pieces dry before firing<\/h3>\n

Allow your pieces to dry overnight before putting them in the kiln.<\/p>\n

Water and kilns are not a good combination.<\/p>\n

If the piece is still damp, the steam released as temperature rises can cause issues such as bubbling or glaze running.<\/p>\n

Again: rushing is not a good idea.<\/p>\n

4. Test. Then test again. And again.<\/h3>\n

Did I mention testing?<\/p>\n

Do not use glazes you haven\u2019t tested before\u2014especially not on pieces you care about.<\/p>\n

I know it\u2019s tempting. You have a beautiful piece and imagine an amazing glaze combination\u2026<\/p>\n

Read that again: in your head.<\/em><\/p>\n

Glazes can behave completely differently depending on:<\/p>\n