If you are interested in throwing or handbuilding functional pottery, it is helpful to know how much clay to prepare. This guilde, available at Ceramic Arts Network (https://ceramicartsnetwork.org/docs/default-source/uploadedfiles/wp-content/uploads/2009/12/potteryclay.pdf) provides some general information on clay as well as guidelines regarding how much clay you will need to complete your project. (See the chart on page 6 of the document for clay weights for various ware types). The weights there may seem to be slightly excessive, but keep in mind that every potter works differently. You will need to figure out what works best for you.
Another chart, available here for download as a pdf, from Lakeside Pottery, gives you a quick reference for your studio.
Click here to download a simple one-page general explanation on mixing glazes in dry form.
Detailed instructions from Laguna on mixing their dry glazes can be downloaded here
This series of videos by AMACO/BRENT covers mixing glazes, dipping, layering and making test tiles (please note that all Potters Choice 25 lb. pails of dry mix have been discontinued)
This post , Using Additives such as CMC Gum to Beef up your Glazes, includes detailed information on how to use glaze additives to expand the possibilities in brushing, dipping and pouring as well as re-glazing your work.
At West Michigan Clay, we sell CMC in powder form. For detailed information on mixing and using this as wellas other gums in your glazes, visit https://ceramicartsnetwork.org/daily/article/Using-Glaze-Additives-to-Make-Average-Glazes-Great.
Equipment and Materials needed:
Your gum solution should have a syrup or glue-like consistency. If the clumps are gone, you are ready to use the gum solution as an additive to glazes.
Mixing your own glazes is money-saving as well as introducing another creative element to your pottery. There are plenty of resources online that provide procedures and recipes for mixing glazes from scratch using raw earth materials that are available at West Michigan Clay. In addition, we recommend the books listed below, which provide background on processes and a great collection of glazes at various firing ranges to get you started.
Safety is an important concern when mixing glazes from dry glaze chemicals. Wear a good face mask to avoid inhaling dust. Some materials ,like wood or bone ash, are caustic and can burn the skin, so you need to wear latex or nitrile gloves to protect your skin when handling these materials.
Glaze materials are measured by weight, not volume. Accurately weighing glaze materials is critical to the outcome of your glazes. Most potters use either a good digital scale or balance.
Adding water to your glaze mix is covered under our FAQ post on mixing dry glazes. Sieve your liquid glazes with an 80 or 100 mesh sieve once they are mixed with water. Use CMC or similar material if brushing your glaze. Adding 1-3% bentonite in your dry mix will help keep the glaze materials in suspension and avoid hardpanning.
The following books - some available at your local library or from Michigan Electronic Library (http://www.mel.org. ) - include a good background on mixing your own glazes and a variety of recipes for mid-range and high-fire glazes.
More general references on glazing and decoration:
Common glaze defects:
This excerpt from the late Robin Hopper's book "The Ceramic Spectrum" covers five common glaze defects with photo illustrations and suggested solutions.
While you might think that glaze defects are less of an issue with commercial glazes, this is not necessarily the case, especially if you are new to making and firing pottery.
If you like to brush your glazes on your ware, or even if you pour/dip and then brush, these two videos may provide some insights that will give you a boost:
In this link (https://www.youtube.com/watch?v=2OOWC_rgJNo) the presenter gives many tips on brushing, brushes and documenting your work and outcome.
Potters, especially those new to the craft, often experience frustration in the glazing process.
The main methods for applying glaze are:
Each method has its pros and cons, which are covered in this article: (https://ceramicartsnetwork.org/pottery-making-illustrated/pottery-making-illustrated-article/8-Ways-to-Apply-Glaze#)
As with any and all methods in making work, you may need to experiment to find what works for you.
The thickness/consistency of the glaze varies by the application method. Again, some experimentation may be necessary to achieve the desired results. Generally, glazes are thickest with brushing, thinner with dipping, somewhat thinner yet with pouring and thinnest for spraying.
Consider using a variety of application methods to obtain the results you seek.
Waxing the bottoms of your pots will help regardless of what application method you choose.
Some simple tips that may help you along the way:
This excerpt from the late Robin Hopper's book 'Making Marks: Decorating the Ceramic Surface" explains the difference between these materials and their application. Commercial underglazes are mostly engobes. You can create your own slips/engobes/underglazes using clay and additional ceramic materials to broaden your creative clay pallette.
Underglaze pencils and pastels can be made from very basic ceramic materials - usually just dry clay, coloring oxides or stains and some bentonite. You can purchase most of the materials at West Michigan Clay - we usually have black stain, but not other colors.
You need to be able to bisque these – how high you go will determine how hard your ‘lead’ will be.
For a video on the process, go to https://www.youtube.com/watch?v=5t7CXeqJ170
For instructions on making your own underglaze pencils and pastels, read this excerpt from Robin Hopper’s “Making Marks: Discovering the Ceramic Surface” at https://ceramicartsnetwork.org/daily/article/drawn-to-surface-how-to-make-and-use-underglaze-pencils-crayons-pens-and-trailers/
It is best to store your moist ceramic materials in a location that avoids temperature extremes. Should you find that your clay and/or glazes have frozen, allow them to thaw before proceeding.
For a detailed explanation on what happens when clay freezes, click here.
YES. Unfired clay is reusable/recyclable and re-wettable. It isn't necessarily quick , but if you are patient, it can be pretty easy.
Yes and no. Yes, you can invest in more trimming tools. But if you have the tools you like, you can SHARPEN THEM.
You may use any number of sharpening tools (files, emery cloth, stones, rotary tools, bench grinders - be gentle with these!). You will probably have more success using more than one sharpening tool, since trimming tools have a wide variety of blade configurations.
Over time and use, your tools will still need to be replaced, but you can prolong their usefulness with proper maintenance.
The two main opacifiers used in making ceramic glazes are zirconium silicate (sold as Zircopax, Ultrox, etc) and tin oxide. Due to the cost difference, glaze recipes often use zirconium silicate to opacify a glaze.
Tin oxide is not as effective as an opacifier for white glazes in high fire reduction. However, the presence or absence of tin oxide impacts the colors produced by metallic oxides in both oxidation and reduction. Because of this, as well as the different kind of 'whiteness' when used to produce white glazes, substituting one opacifier for another is not straightforward.
See this post on Ceramic Arts Network for a demonstration of differences in applying each of these two opacifiers.
If you recently invested in a new or used electric kiln, you may have some questions about long-term maintenance and repair. These are the parts of your kiln that will likely require some attention from time to time:
TROUBLESHOOTING KILN PROBLEMS:
BE CAREFUL IF YOU CHOOSE TO TAKE ON YOUR OWN KILN REPAIR - KILNS PACK A POWERFUL PUNCH OF POTENTIALLY DEADLY CURRENT. Ensure that the power source to the kiln is disabled before doing any work on your kiln. IF IN DOUBT, HIRE A QUALIFIED ELECTRICIAN FOR YOUR REPAIRS.
Here are some resources that you may find helpful: