When it involves glazing within the classroom, it’s not unusual to seek out that extra focus is placed on the constructing of the clay piece somewhat than the end. While in some regards, this is smart as you’ll want to have a clay piece constructed to glaze it, this usually means the glazing course of is an afterthought. Yes, glazing is likely one of the most magical elements of the ceramic course of, nevertheless it’s essential to grasp its intricacies.
There are so many various strategies and ideas to grasp about glazing, and this text received’t cowl all of them. However, it would give you a primary understanding that can assist you really feel extra snug with the glazing course of in your artwork room!
What is Glaze?
Glaze may be considered a glass coating that fuses to the ceramic floor throughout firing. It seals the piece making it stain-resistant and, relying on the glaze, meals protected. Glazes can take many kinds: they are often both clear clear or, with the addition of steel in any of a number of kinds, in a rainbow of colours. They may be shiny or matte, translucent or opaque, easy, and even textured.
Uses of Glaze:
Know Your Clay Body
Before buying glaze, you could know the sorts of clay our bodies college students will likely be utilizing in your classroom. Low-fire clay our bodies are generally used within the classroom setting. No matter what clay physique you’re utilizing, it’s important that your glaze suits. By “fit,” we imply that the right glaze is used for the clay physique. For instance, low fireplace glazes must be used on low fireplace clay. If you unintentionally put a excessive fireplace glaze on a low fireplace clay physique, the outcome isn’t going to return out as deliberate.
During the firing course of, each the clay physique and glaze increase due to warmth. If they don’t seem to be increasing collectively on the acceptable temperatures, issues come up. These issues aren’t all the time seen on the clay floor however dwell inside the ceramic partitions and, over time, can develop into problematic.
To allow you to decide the suitable sorts of clay our bodies and glazes, be sure to are listening to temperatures.
Use this listing to assist:
- Low Fire: Cone 04 to Cone 06 (1828 – 1945°F)
- Mid Range: Cone four to Cone 7 (2167 – 2264°F)
- High Fire: Cone eight to Cone 14 (2305-2530°F)
Visualize Glaze Coverage
Certain varieties, colours, and types of business glazes don’t all the time prove the identical. For instance, some glazes are extra opaque than others, whereas others are extra translucent. Knowing how glazes are going to prove is likely one of the many causes it’s essential to create test tiles, nevertheless it’s additionally essential to notice that sure glazes are going to require a distinct quantity of protection.
While it’s good to abide by the rule of making use of three coats of glaze for full protection, this isn’t all the time going to be the case. Some colours are going to look finest with 4 coats. Some colours would possibly have to be layered with different glazes to get the specified impact. It’s essential to understand how glaze colours are going to prove to finest assist our college students within the creating course of. Consider creating pattern glaze tiles that present how completely different coats of glaze have an effect on the ultimate outcome. To make your college students really feel much more snug with the glazing course of, have them practice first!
Reviving Dry Glazes
Have you ever inherited an artwork room with bottles of dried glaze? It’s unlucky to suppose that you simply’ll need to throw them away as a result of we all know how costly glazes may be. Here’s the excellent news, it can save you these dried glazes! You can do that by including in small quantities of distilled water. Be cautious to not overdo it, as you may skinny the glazes out, making them much less opaque. Another nice answer to assist the circulate and consistency of dried glazes is to make use of a gum solution.
Troubleshooting Common Glaze Problems
Have you ever taken a glazed clay piece out of the kiln to seek out that one thing isn’t fairly proper? Maybe it appears just like the glaze has pooled as much as reveal the bisque floor? Maybe, there are areas on the clay piece that look as if the glaze has flaked off. It’s essential to have the ability to determine these issues once they come up so you may troubleshoot and stop it from occurring once more. Here are a number of the most typical points with glazing.
- Crazing: Appears to be small cracks on the glaze floor and is a results of the glaze having the next growth charge than the clay physique.
- Shivering: The reverse of crazing, the place the glaze peels or flakes off to disclose the bisque floor. This is because of the glaze having a decrease growth charge than the clay physique.
- Crawling: Typically happens due to dangerous utility of glaze—mostly attributable to overapplication. It swimming pools as much as expose the bisque floor.
- Pinholes: Appear to be tiny holes within the glazed floor and is a results of a foul firing course of. Typically this happens when the bisque firing leads to an underfired clay physique, which signifies that not all the gasses have been capable of escape inflicting it to have an effect on the glaze. This is why it’s essential to bisque fireplace your items first and never bisque and glaze your items in a single firing.
For extra concepts on the best way to fix these common mistakes, take a look at this info.
Glazing is fascinating, however should you’re new to the method, it may be overwhelming. There is an excessive amount of chemistry that goes into the complexity of glazing. Just understanding just a few of those ideas will allow you to and your college students have a greater total ceramics expertise.
What do you discover difficult concerning the glazing course of?
What’s your favourite factor about glaze?